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  • richardmitnick 3:15 pm on April 12, 2021 Permalink | Reply
    Tags: , , , , , Flares from the Milky Way’s Supermassive Black Hole, Sky & Telescope   

    From AAS NOVA via From Sky & Telescope : “Flares from the Milky Way’s Supermassive Black Hole” 

    AASNOVA

    From AAS NOVA

    via

    Sky & Telescope

    April 12, 2021

    The supermassive black hole at the center of the Milky Way released an unusual number of strong flares in 2019. Now, astronomers are trying to figure out why.

    1
    Artist’s impression of the disruption of a gas cloud as it passes close to Sgr A*, the supermassive black hole at the center of our galaxy.
    European Southern Observatory(EU) / MPG Institute for extraterrestrial Physics [MPG Institut für extraterrestrische Physik] ( DE)/ Marc Schartmann

    In 2019, the supermassive black hole at the center of our galaxy woke up and emitted a series of burps. A new study now examines what meal may have led to this indigestion.

    Waking Up for a Snack

    3
    Artist’s impression of the dramatic outflows from an active galaxy’s nucleus. The Milky Way’s supermassive black hole, in contrast, is very quiet.

    Lynette Cook

    Sgr A*, the 4.6-million-solar-mass black hole that lies at the center of the Milky Way, is normally a fairly quiet beast. The black hole slowly feeds on accreting material in the galactic center — but this food source is sparse, and Sgr A*’s accretion doesn’t produce anything like the fireworks we associate with supermassive black holes in active galaxies.

    In May 2019, however, Sgr A* suddenly became substantially more active than usual, producing an unprecedented bright, near-infrared flare that lasted roughly 2.5 hours. This flare was more than 100 times brighter than the typical emission from Sgr A*’s casual accretion, and more than twice as bright as the brightest flare we’ve ever measured from our neighborhood monster.

    The May 2019 flare marked the start of prolonged increased activity — an unusual number of strong flares that continued at least throughout 2019 (currently analyzed data extends only to the end of that year). What caused Sgr A* to wake up? And do we expect more flaring ahead? A new study by Lena Murchikova (Institute for Advanced Study (US)) explores the options.

    Star S0-2 Andrea Ghez Keck/UCLA Galactic Center Group (US) at SGR A*, the supermassive black hole at the center of the Milky Way.

    Sgr A*’s flares likely came from an abrupt increase in the amount of material available to accrete onto this black hole. Murchikova identifies two likely sources of this excess material.

    Shedding S stars
    The dense nucleus of our galaxy hosts a population of stars on tight orbits around Sgr A*. These stars shed mass via stellar winds, and when the stars swing close around Sgr A* at the pericenter of their orbit, this shed mass could accrete onto Sgr A*.
    Disintegrating G objects
    Also known to orbit close to Sgr A* are so-called G objects. These extended sources may be gas clouds, stars, or a combination of the two — we’re not sure yet! Tenuous G objects lose mass as a result of friction as they orbit, exhibiting higher rates of mass loss as they get closer to Sgr A* and are stretched out into shapes with large surfaces areas passing through dense background material. The mass they lose through this disintegration at pericenter could then accrete onto Sgr A*.

    3
    The objects G2 (colored red) and G1 (colored blue) and the star S2 are visible in these high-resolution images of the galactic center, taken in 2006 (left) and in 2008 (right). The position of Sgr A* is marked with an X.
    SOFIA / Lynette Cook [above]

    Through a series of calculations, Murchikova estimates how much material is shed by these two types of objects and how long it would take that material to accrete onto Sgr A*. Based on the available observations, the author finds that the most likely explanation for our black hole’s unexpected rumblings in 2019 is currently accreting material from the combined past pericenter passages of the objects G1 and G2.

    If this interpretation is correct, we would expect to see flaring continue for a limited time, but Sgr A* should then return to its quiescent state. If the flaring was instead a part of normal variability in the flow of accreting material onto Sgr A*, we would expect the activity to continue for years to come. Continued observations of this rumbling giant will tell!

    Citation

    “S0-2 Star, G1- and G2-objects, and Flaring Activity of the Milky Way’s Galactic Center Black Hole in 2019,” Lena Murchikova 2021 ApJL 910 L1. https://iopscience.iop.org/article/10.3847/2041-8213/abeb70

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

    Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

    Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

    “Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

    From AAS NOVA

    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

    The society was founded in 1899 through the efforts of George Ellery Hale. The constitution of the group was written by Hale, George Comstock, Edward Morley, Simon Newcomb and Edward Charles Pickering. These men, plus four others, were the first Executive Council of the society; Newcomb was the first president. The initial membership was 114. The AAS name of the society was not finally decided until 1915, previously it was the “Astronomical and Astrophysical Society of America”. One proposed name that preceded this interim name was “American Astrophysical Society”.

    The AAS today has over 7,000 members and six divisions – the Division for Planetary Sciences (1968); the Division on Dynamical Astronomy (1969); the High Energy Astrophysics Division (1969); the Solar Physics Division (1969); the Historical Astronomy Division (1980); and the Laboratory Astrophysics Division (2012). The membership includes physicists, mathematicians, geologists, engineers and others whose research interests lie within the broad spectrum of subjects now comprising contemporary astronomy.

    In 2019 three AAS members were selected into the tenth anniversary class of TED Fellows.

    The AAS established the AAS Fellows program in 2019 to “confer recognition upon AAS members for achievement and extraordinary service to the field of astronomy and the American Astronomical Society.” The inaugural class was designated by the AAS Board of Trustees and includes an initial group of 232 Legacy Fellows.

     
  • richardmitnick 4:08 pm on March 26, 2021 Permalink | Reply
    Tags: "The Milky Way’s Local Arm Is Longer Than We Thought", , , , , , Sky & Telescope,   

    From European Space Agency [Agence spatiale européenne] [Europäische Weltraumorganisation](EU) via Sky & Telescope : “The Milky Way’s Local Arm Is Longer Than We Thought” 

    ESA Space For Europe Banner

    From European Space Agency – United Space in Europe (EU)
    From European Space Agency [Agence spatiale européenne] [Europäische Weltraumorganisation](EU)

    via

    Sky & Telescope

    March 23, 2021
    Monica Young

    The ancients gazed at the Milky Way for millennia, but it wasn’t until the mid-20th century that we discovered we live in a galaxy that takes a spiral shape.

    New maps of the Milky Way suggest the Local Arm that we call home is longer than expected, now upgraded to a major spiral feature (but not quite an arm).

    1
    This artist’s concept shows our Milky Way galaxy, but recent studies suggest the Local Arm might be longer than what’s depicted here. Credit: R. Hurt / National Aeronautics Space Agency(USA)/
    JPL-Caltech /

    But while astronomers now generally agree that our spiral has four major arms, what they actually look like is still open to question. That includes the Local Arm that we call home (which may or may not be an arm at all).

    Two recent studies of the latest data release from the European Space Agency’s Gaia mission suggest our part of the spiral might not be as rural as once thought. The Local Arm gets an upgrade to a major spiral feature in the new maps, published in the January Astronomy & Astrophysics and also separately Astronomy & Astrophysics, respectively.

    Mapping the Milky Way

    Determining the details of galactic structure is difficult because we’re mapping our galaxy from within, which is a bit like trying to tell what kind of plane you’re flying in by looking out the tiny porthole window. Not only is a bird’s-eye view forever out of reach, there’s also interstellar material blocking our view.

    Even with those limitations in mind, how we see our galaxy depends on what we’re looking at. Some studies have measured 21-centimeter radio waves from hydrogen gas that suffuses the galaxy, the fuel for new star formation. Other studies have mapped hydrogen gas ionized by ultraviolet emission pouring out of stellar newborns. Still others look at radio masers, which trace shocks driven by young stellar winds.

    Astronomers have used all these methods to trace stellar nurseries, which mark spiral arms in other galaxies and presumably our own. But it’s a case of blind men examining the proverbial elephant. Studies differ on the length and angles of the arms. The nature of the Local Arm also depends on the technique used to measure it.

    With the advent of the Gaia mission, which is mapping exact positions and motions of a billion stars, Milky Way maps have experienced something of a renaissance. In recent months, two independent teams have set out to recast the local spiral structure: one led by Ye Xu (Purple Mountain Observatory (CN), Chinese Academy of Sciences(CN)) and the other by Eloisa Poggio (University of Côte d’Azur [Université Côte d’Azur](FR)).

    Xu and his colleagues used the latest Gaia data release [EDR3] to select almost 10,000 stars of spectral type O to B2, massive and brilliant stars that are at most 20 million years old and thus not too far from their birthplaces in the spiral arms.

    Meanwhile, Poggio and her colleagues mapped more than 750,000 of the most massive main-sequence stars, almost 700 newborn star clusters, and nearly 2,000 young Cepheid variables, giant pulsating stars with well-known distances. This team is working with more objects and thus has better statistics. But the stars and stellar groups are all somewhat older (though still less than 100 million years old); with more time to travel away from the spiral arm they were born in, they give a fuzzier view of the spiral structure.

    A Longer Local Arm, and a Less Grand Milky Way

    Despite their differences, both studies find that the Local Arm is longer than expected, between 23,000 and 26,000 light-years long. The finding upgrades it to a major spiral feature, if not quite a full-size arm.

    2
    The Milky Way’s spiral structure near the Sun is divided into four spiral features (from the inner galaxy out): the Scutum-Centaurus Arm (green), the Sagittarius-Carina Arm (purple), the Local Arm (blue), and the Perseus Arm (black). Radio masers (triangles) trace the arms most faithfully due to their youth, but masers only cover a third of the Milky Way. Xu’s team turned to the most massive O and B stars (red) to add more data, tracing out a longer Local Arm than expected. In the team’s data, the Local Arm appears to bend inward toward the left. Credit: Xu et al.https://www.aanda.org/articles/aa/full_html/2021/01/aa40103-20/aa40103-20.html.

    But the teams still don’t agree on what the Local Arm looks like. While Xu’s team finds that the arm might bend, spiraling inward, the map made by Poggio’s team shows it as a nearly straight line. The Local Arm may also have a large gap, which makes it hard to identify different sections that belong to it, says Mark Reid (Harvard Smithsonian Center for Astrophysics(US)), who was not involved in the study.

    “Spiral arms do not have a single, constant pitch angle,” Reid explains. “Instead, they appear to be formed out of segments which have markedly different pitch angles.”

    Astronomers have long thought that spiral arms form via density waves, in which stars circling the galactic center pile up in spiral-shaped traffic jams. While many stars are born in the traffic jam, they eventually sail through, but the traffic jam stays in place.

    However, the raggedy shape of the Milky Way’s arms, including the Local Arm’s segmentation, could point to a different scenario, one in which clumps of stars form and then elongate into arm segments. Those segments join up to form longer arms, but there’s no true spiral shape that’s maintained over time.

    The same mechanism isn’t necessarily at work everywhere; two-armed “grand-design” spirals might still originate as traffic jams. But evidence suggests that Milky Way is not of the grand-design variety.

    As Gaia continues to deliver increasingly precise measurements of stars’ positions in our galaxy, especially the younger and fainter (and thus more distant) ones, astronomers will be able to confirm the details of the arm we live in, as well as the other arms of the Milky Way.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    From European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

    ESA’s space flight programme includes human spaceflight (mainly through participation in the International Space Station program); the launch and operation of uncrewed exploration missions to other planets and the Moon; Earth observation, science and telecommunication; designing launch vehicles; and maintaining a major spaceport, the The Guiana Space Centre [Centre Spatial Guyanais; CSG also called Europe’s Spaceport) at Kourou, French Guiana. The main European launch vehicle Ariane 5 is operated through Arianespace with ESA sharing in the costs of launching and further developing this launch vehicle. The agency is also working with NASA to manufacture the Orion Spacecraft service module that will fly on the Space Launch System.

    The agency’s facilities are distributed among the following centres:

    ESA science missions are based at ESTEC in Noordwijk, Netherlands;
    Earth Observation missions at ESA Centre for Earth Observation in Frascati, Italy;
    ESA Mission Control (ESOC) is in Darmstadt, Germany;
    the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany;
    the European Centre for Space Applications and Telecommunications (ECSAT), a research institute created in 2009, is located in Harwell, England;
    and the European Space Astronomy Centre (ESAC) is located in Villanueva de la Cañada, Madrid, Spain.

    The European Space Agency Science Programme is a long-term programme of space science and space exploration missions.

    Foundation

    After World War II, many European scientists left Western Europe in order to work with the United States. Although the 1950s boom made it possible for Western European countries to invest in research and specifically in space-related activities, Western European scientists realized solely national projects would not be able to compete with the two main superpowers. In 1958, only months after the Sputnik shock, Edoardo Amaldi (Italy) and Pierre Auger (France), two prominent members of the Western European scientific community, met to discuss the foundation of a common Western European space agency. The meeting was attended by scientific representatives from eight countries, including Harrie Massey (United Kingdom).

    The Western European nations decided to have two agencies: one concerned with developing a launch system, ELDO (European Launch Development Organization), and the other the precursor of the European Space Agency, ESRO (European Space Research Organisation). The latter was established on 20 March 1964 by an agreement signed on 14 June 1962. From 1968 to 1972, ESRO launched seven research satellites.

    ESA in its current form was founded with the ESA Convention in 1975, when ESRO was merged with ELDO. ESA had ten founding member states: Belgium, Denmark, France, West Germany, Italy, the Netherlands, Spain, Sweden, Switzerland, and the United Kingdom. These signed the ESA Convention in 1975 and deposited the instruments of ratification by 1980, when the convention came into force. During this interval the agency functioned in a de facto fashion. ESA launched its first major scientific mission in 1975, Cos-B, a space probe monitoring gamma-ray emissions in the universe, which was first worked on by ESRO.

    ESA50 Logo large

    Later activities

    ESA collaborated with National Aeronautics Space Agency on the International Ultraviolet Explorer (IUE), the world’s first high-orbit telescope, which was launched in 1978 and operated successfully for 18 years. A number of successful Earth-orbit projects followed, and in 1986 ESA began Giotto, its first deep-space mission, to study the comets Halley and Grigg–Skjellerup. Hipparcos, a star-mapping mission, was launched in 1989 and in the 1990s SOHO, Ulysses and the Hubble Space Telescope were all jointly carried out with NASA. Later scientific missions in cooperation with NASA include the Cassini–Huygens space probe, to which ESA contributed by building the Titan landing module Huygens.

    As the successor of ELDO, ESA has also constructed rockets for scientific and commercial payloads. Ariane 1, launched in 1979, carried mostly commercial payloads into orbit from 1984 onward. The next two versions of the Ariane rocket were intermediate stages in the development of a more advanced launch system, the Ariane 4, which operated between 1988 and 2003 and established ESA as the world leader in commercial space launches in the 1990s. Although the succeeding Ariane 5 experienced a failure on its first flight, it has since firmly established itself within the heavily competitive commercial space launch market with 82 successful launches until 2018. The successor launch vehicle of Ariane 5, the Ariane 6, is under development and is envisioned to enter service in the 2020s.

    The beginning of the new millennium saw ESA become, along with agencies like National Aeronautics Space Agency(US), Japan Aerospace Exploration Agency, Indian Space Research Organisation, the Canadian Space Agency(CA) and Roscosmos(RU), one of the major participants in scientific space research. Although ESA had relied on co-operation with NASA in previous decades, especially the 1990s, changed circumstances (such as tough legal restrictions on information sharing by the United States military) led to decisions to rely more on itself and on co-operation with Russia. A 2011 press issue thus stated:

    “Russia is ESA’s first partner in its efforts to ensure long-term access to space. There is a framework agreement between ESA and the government of the Russian Federation on cooperation and partnership in the exploration and use of outer space for peaceful purposes, and cooperation is already underway in two different areas of launcher activity that will bring benefits to both partners.”

    Notable ESA programmes include SMART-1, a probe testing cutting-edge space propulsion technology, the Mars Express and Venus Express missions, as well as the development of the Ariane 5 rocket and its role in the ISS partnership. ESA maintains its scientific and research projects mainly for astronomy-space missions such as Corot, launched on 27 December 2006, a milestone in the search for exoplanets.

    On 21 January 2019, ArianeGroup and Arianespace announced a one-year contract with ESA to study and prepare for a mission to mine the Moon for lunar regolith.

    Mission

    The treaty establishing the European Space Agency reads:

    The purpose of the Agency shall be to provide for and to promote, for exclusively peaceful purposes, cooperation among European States in space research and technology and their space applications, with a view to their being used for scientific purposes and for operational space applications systems…

    ESA is responsible for setting a unified space and related industrial policy, recommending space objectives to the member states, and integrating national programs like satellite development, into the European program as much as possible.

    Jean-Jacques Dordain – ESA’s Director General (2003–2015) – outlined the European Space Agency’s mission in a 2003 interview:

    “Today space activities have pursued the benefit of citizens, and citizens are asking for a better quality of life on Earth. They want greater security and economic wealth, but they also want to pursue their dreams, to increase their knowledge, and they want younger people to be attracted to the pursuit of science and technology. I think that space can do all of this: it can produce a higher quality of life, better security, more economic wealth, and also fulfill our citizens’ dreams and thirst for knowledge, and attract the young generation. This is the reason space exploration is an integral part of overall space activities. It has always been so, and it will be even more important in the future.”

    Activities

    According to the ESA website, the activities are:

    Observing the Earth
    Human Spaceflight
    Launchers
    Navigation
    Space Science
    Space Engineering & Technology
    Operations
    Telecommunications & Integrated Applications
    Preparing for the Future
    Space for Climate

    Programmes

    Copernicus Programme
    Cosmic Vision
    ExoMars
    FAST20XX
    Galileo
    Horizon 2000
    Living Planet Programme

    Mandatory

    Every member country must contribute to these programmes:

    Technology Development Element Programme
    Science Core Technology Programme
    General Study Programme
    European Component Initiative

    Optional

    Depending on their individual choices the countries can contribute to the following programmes, listed according to:

    Launchers
    Earth Observation
    Human Spaceflight and Exploration
    Telecommunications
    Navigation
    Space Situational Awareness
    Technology

    ESA_LAB@

    ESA has formed partnerships with universities. ESA_LAB@ refers to research laboratories at universities. Currently there are ESA_LAB@

    Technische Universität Darmstadt
    École des hautes études commerciales de Paris (HEC Paris)
    Université de recherche Paris Sciences et Lettres
    University of Central Lancashire

    Membership and contribution to ESA

    By 2015, ESA was an intergovernmental organisation of 22 member states. Member states participate to varying degrees in the mandatory (25% of total expenditures in 2008) and optional space programmes (75% of total expenditures in 2008). The 2008 budget amounted to €3.0 billion whilst the 2009 budget amounted to €3.6 billion. The total budget amounted to about €3.7 billion in 2010, €3.99 billion in 2011, €4.02 billion in 2012, €4.28 billion in 2013, €4.10 billion in 2014 and €4.33 billion in 2015. English is the main language within ESA. Additionally, official documents are also provided in German and documents regarding the Spacelab are also provided in Italian. If found appropriate, the agency may conduct its correspondence in any language of a member state.

    Non-full member states
    Slovenia
    Since 2016, Slovenia has been an associated member of the ESA.

    Latvia
    Latvia became the second current associated member on 30 June 2020, when the Association Agreement was signed by ESA Director Jan Wörner and the Minister of Education and Science of Latvia, Ilga Šuplinska in Riga. The Saeima ratified it on July 27. Previously associated members were Austria, Norway and Finland, all of which later joined ESA as full members.

    Canada
    Since 1 January 1979, Canada has had the special status of a Cooperating State within ESA. By virtue of this accord, the Canadian Space Agency takes part in ESA’s deliberative bodies and decision-making and also in ESA’s programmes and activities. Canadian firms can bid for and receive contracts to work on programmes. The accord has a provision ensuring a fair industrial return to Canada. The most recent Cooperation Agreement was signed on 15 December 2010 with a term extending to 2020. For 2014, Canada’s annual assessed contribution to the ESA general budget was €6,059,449 (CAD$8,559,050). For 2017, Canada has increased its annual contribution to €21,600,000 (CAD$30,000,000).

    Enlargement

    After the decision of the ESA Council of 21/22 March 2001, the procedure for accession of the European states was detailed as described the document titled The Plan for European Co-operating States (PECS). Nations that want to become a full member of ESA do so in 3 stages. First a Cooperation Agreement is signed between the country and ESA. In this stage, the country has very limited financial responsibilities. If a country wants to co-operate more fully with ESA, it signs a European Cooperating State (ECS) Agreement. The ECS Agreement makes companies based in the country eligible for participation in ESA procurements. The country can also participate in all ESA programmes, except for the Basic Technology Research Programme. While the financial contribution of the country concerned increases, it is still much lower than that of a full member state. The agreement is normally followed by a Plan For European Cooperating State (or PECS Charter). This is a 5-year programme of basic research and development activities aimed at improving the nation’s space industry capacity. At the end of the 5-year period, the country can either begin negotiations to become a full member state or an associated state or sign a new PECS Charter.

    During the Ministerial Meeting in December 2014, ESA ministers approved a resolution calling for discussions to begin with Israel, Australia and South Africa on future association agreements. The ministers noted that “concrete cooperation is at an advanced stage” with these nations and that “prospects for mutual benefits are existing”.

    A separate space exploration strategy resolution calls for further co-operation with the United States, Russia and China on “LEO exploration, including a continuation of ISS cooperation and the development of a robust plan for the coordinated use of space transportation vehicles and systems for exploration purposes, participation in robotic missions for the exploration of the Moon, the robotic exploration of Mars, leading to a broad Mars Sample Return mission in which Europe should be involved as a full partner, and human missions beyond LEO in the longer term.”

    Relationship with the European Union

    The political perspective of the European Union (EU) was to make ESA an agency of the EU by 2014, although this date was not met. The EU member states provide most of ESA’s funding, and they are all either full ESA members or observers.

    History

    At the time ESA was formed, its main goals did not encompass human space flight; rather it considered itself to be primarily a scientific research organisation for uncrewed space exploration in contrast to its American and Soviet counterparts. It is therefore not surprising that the first non-Soviet European in space was not an ESA astronaut on a European space craft; it was Czechoslovak Vladimír Remek who in 1978 became the first non-Soviet or American in space (the first man in space being Yuri Gagarin of the Soviet Union) – on a Soviet Soyuz spacecraft, followed by the Pole Mirosław Hermaszewski and East German Sigmund Jähn in the same year. This Soviet co-operation programme, known as Intercosmos, primarily involved the participation of Eastern bloc countries. In 1982, however, Jean-Loup Chrétien became the first non-Communist Bloc astronaut on a flight to the Soviet Salyut 7 space station.

    Because Chrétien did not officially fly into space as an ESA astronaut, but rather as a member of the French CNES astronaut corps, the German Ulf Merbold is considered the first ESA astronaut to fly into space. He participated in the STS-9 Space Shuttle mission that included the first use of the European-built Spacelab in 1983. STS-9 marked the beginning of an extensive ESA/NASA joint partnership that included dozens of space flights of ESA astronauts in the following years. Some of these missions with Spacelab were fully funded and organizationally and scientifically controlled by ESA (such as two missions by Germany and one by Japan) with European astronauts as full crew members rather than guests on board. Beside paying for Spacelab flights and seats on the shuttles, ESA continued its human space flight co-operation with the Soviet Union and later Russia, including numerous visits to Mir.

    During the latter half of the 1980s, European human space flights changed from being the exception to routine and therefore, in 1990, the European Astronaut Centre in Cologne, Germany was established. It selects and trains prospective astronauts and is responsible for the co-ordination with international partners, especially with regard to the International Space Station. As of 2006, the ESA astronaut corps officially included twelve members, including nationals from most large European countries except the United Kingdom.

    In the summer of 2008, ESA started to recruit new astronauts so that final selection would be due in spring 2009. Almost 10,000 people registered as astronaut candidates before registration ended in June 2008. 8,413 fulfilled the initial application criteria. Of the applicants, 918 were chosen to take part in the first stage of psychological testing, which narrowed down the field to 192. After two-stage psychological tests and medical evaluation in early 2009, as well as formal interviews, six new members of the European Astronaut Corps were selected – five men and one woman.

    Cooperation with other countries and organisations

    ESA has signed co-operation agreements with the following states that currently neither plan to integrate as tightly with ESA institutions as Canada, nor envision future membership of ESA: Argentina, Brazil, China, India (for the Chandrayan mission), Russia and Turkey.

    Additionally, ESA has joint projects with the European Union, NASA of the United States and is participating in the International Space Station together with the United States (NASA), Russia and Japan (JAXA).

    European Union
    ESA and EU member states
    ESA-only members
    EU-only members

    ESA is not an agency or body of the European Union (EU), and has non-EU countries (Norway, Switzerland, and the United Kingdom) as members. There are however ties between the two, with various agreements in place and being worked on, to define the legal status of ESA with regard to the EU.

    There are common goals between ESA and the EU. ESA has an EU liaison office in Brussels. On certain projects, the EU and ESA co-operate, such as the upcoming Galileo satellite navigation system. Space policy has since December 2009 been an area for voting in the European Council. Under the European Space Policy of 2007, the EU, ESA and its Member States committed themselves to increasing co-ordination of their activities and programmes and to organising their respective roles relating to space.

    The Lisbon Treaty of 2009 reinforces the case for space in Europe and strengthens the role of ESA as an R&D space agency. Article 189 of the Treaty gives the EU a mandate to elaborate a European space policy and take related measures, and provides that the EU should establish appropriate relations with ESA.

    Former Italian astronaut Umberto Guidoni, during his tenure as a Member of the European Parliament from 2004 to 2009, stressed the importance of the European Union as a driving force for space exploration, “…since other players are coming up such as India and China it is becoming ever more important that Europeans can have an independent access to space. We have to invest more into space research and technology in order to have an industry capable of competing with other international players.”

    The first EU-ESA International Conference on Human Space Exploration took place in Prague on 22 and 23 October 2009. A road map which would lead to a common vision and strategic planning in the area of space exploration was discussed. Ministers from all 29 EU and ESA members as well as members of parliament were in attendance.

    National space organisations of member states:

    The Centre National d’Études Spatiales(FR) (CNES) (National Centre for Space Study) is the French government space agency (administratively, a “public establishment of industrial and commercial character”). Its headquarters are in central Paris. CNES is the main participant on the Ariane project. Indeed, CNES designed and tested all Ariane family rockets (mainly from its centre in Évry near Paris)
    The UK Space Agency is a partnership of the UK government departments which are active in space. Through the UK Space Agency, the partners provide delegates to represent the UK on the various ESA governing bodies. Each partner funds its own programme.
    The Italian Space Agency A.S.I. – Agenzia Spaziale Italiana was founded in 1988 to promote, co-ordinate and conduct space activities in Italy. Operating under the Ministry of the Universities and of Scientific and Technological Research, the agency cooperates with numerous entities active in space technology and with the president of the Council of Ministers. Internationally, the ASI provides Italy’s delegation to the Council of the European Space Agency and to its subordinate bodies.
    The German Aerospace Center (DLR)[Deutsches Zentrum für Luft- und Raumfahrt e. V.] is the national research centre for aviation and space flight of the Federal Republic of Germany and of other member states in the Helmholtz Association. Its extensive research and development projects are included in national and international cooperative programmes. In addition to its research projects, the centre is the assigned space agency of Germany bestowing headquarters of German space flight activities and its associates.
    The Instituto Nacional de Técnica Aeroespacial (INTA)(ES) (National Institute for Aerospace Technique) is a Public Research Organization specialised in aerospace research and technology development in Spain. Among other functions, it serves as a platform for space research and acts as a significant testing facility for the aeronautic and space sector in the country.

    NASA

    ESA has a long history of collaboration with NASA. Since ESA’s astronaut corps was formed, the Space Shuttle has been the primary launch vehicle used by ESA’s astronauts to get into space through partnership programmes with NASA. In the 1980s and 1990s, the Spacelab programme was an ESA-NASA joint research programme that had ESA develop and manufacture orbital labs for the Space Shuttle for several flights on which ESA participate with astronauts in experiments.

    In robotic science mission and exploration missions, NASA has been ESA’s main partner. Cassini–Huygens was a joint NASA-ESA mission, along with the Infrared Space Observatory, INTEGRAL, SOHO, and others. Also, the Hubble Space Telescope is a joint project of NASA and ESA. Future ESA-NASA joint projects include the James Webb Space Telescope and the proposed Laser Interferometer Space Antenna. NASA has committed to provide support to ESA’s proposed MarcoPolo-R mission to return an asteroid sample to Earth for further analysis. NASA and ESA will also likely join together for a Mars Sample Return Mission. In October 2020 the ESA entered into a memorandum of understanding (MOU) with NASA to work together on the Artemis program, which will provide an orbiting lunar gateway and also accomplish the first manned lunar landing in 50 years, whose team will include the first woman on the Moon. Astronaut selection announcements are expected within two years of the 2024 scheduled launch date.

    Cooperation with other space agencies

    Since China has started to invest more money into space activities, the Chinese Space Agency(CN) has sought international partnerships. ESA is, beside the Russian Space Agency, one of its most important partners. Two space agencies cooperated in the development of the Double Star Mission. In 2017, ESA sent two astronauts to China for two weeks sea survival training with Chinese astronauts in Yantai, Shandong.

    ESA entered into a major joint venture with Russia in the form of the CSTS, the preparation of French Guiana spaceport for launches of Soyuz-2 rockets and other projects. With India, ESA agreed to send instruments into space aboard the ISRO’s Chandrayaan-1 in 2008. ESA is also co-operating with Japan, the most notable current project in collaboration with JAXA is the BepiColombo mission to Mercury.

    Speaking to reporters at an air show near Moscow in August 2011, ESA head Jean-Jacques Dordain said ESA and Russia’s Roskosmos space agency would “carry out the first flight to Mars together.”

     
  • richardmitnick 4:41 pm on March 19, 2021 Permalink | Reply
    Tags: "Karma Asteroid Family Might Be Sending Members Near Earth", , , , , Eventually the lost Karma members cross Mars’s orbit to become near-Earth asteroids., Kirkwood gap: an unstable region of the main belt around 2½ times farther out from the Sun than Earth's orbit., Sky & Telescope, The Karma family is named after its largest member asteroid 3811 Karma discovered in 1953., University of Belgrade [Универзитет у Београду](RS)(CZ),   

    From University of Belgrade [Универзитет у Београду](RS)(CZ) via Sky & Telescope: “Karma Asteroid Family Might Be Sending Members Near Earth” 

    From University of Belgrade [Универзитет у Београду](RS)(CZ)

    via

    Sky & Telescope

    March 15, 2021
    Theo Nicitopoulos

    1
    This artist’s illustration shows a near-Earth asteroid passing by Earth.
    Credit: NASA / JPL-Caltech

    In a study published in MNRAS, researchers simulated the orbital evolution of asteroids in the Karma family, starting with the initial family-creating impact. The results suggest that over the family’s lifetime, 350 members have transferred close to Earth’s orbit — and around 10 might currently be in near-Earth space right now.

    The Karma Family

    The Karma family is named after its largest member asteroid 3811 Karma discovered in 1953. The researchers estimate that approximately 137 million years ago, another object hit a body between 34 and 41 kilometers wide (21 to 25 miles), splintering off unknown numbers of family members. They’re carbonaceous chondrites, so they reflect little light and are therefore difficult to find.

    “However, new sky surveys within the last couple of years have been able to observe the tiny specks of light of these fainter asteroids, and these observations allowed us to identify 317 Karma family members,” says undergraduate student and lead author Debora Pavela (University of Belgrade).

    The researchers simulated the evolution of the members’ orbits beginning with the family-making collision. In addition to the gravitational pull of the planets, the researchers also included the Yarkovsky effect, in which the tiny push resulting from solar heating can cause asteroids to drift across vast distances over millions of years.

    2
    A spinning body radiates the most heat from its afternoon side, creating a slight thermal imbalance called the Yarkovsky effect. Over time an asteroid rotating in the same sense as its motion around the Sun is gradually accelerated and pushed into a wider orbit. Conversely, a retrograde spinner will spiral inward. Credit: Sky & Telescope.

    Near-Earth Asteroids

    The simulations show that over the family’s lifetime, the Yarkovsky effect caused 350 large asteroids (more than 1 kilometer in diameter) to migrate to the so-called Kirkwood gap: an unstable region of the main belt around 2½ times farther out from the Sun than Earth’s orbit. Here, the asteroids experience a 3:1 mean-motion resonance with Jupiter, completing three orbits for every one orbit of Jupiter. As Jupiter repeatedly tugs more strongly at certain relative positions, the asteroids’ orbits gradually elongate. Eventually the lost Karma members cross Mars’s orbit to become near-Earth asteroids, Pavela says.

    According to the simulations, the first asteroid entered the 3:1 resonance approximately 70 million years ago, and roughly 5 additional family members come in every million years or so.

    Based on past studies that show most asteroids entering this resonance end up as near-Earth asteroids, remaining in near-Earth space for about 2 million years, coauthor Bojan Novakovic (University of Belgrade) estimates there are currently 10 asteroids from the Karma family in the near-Earth region.

    “The Yarkovsky effect together with the resonance is interesting, because you can potentially get a meteorite from any part of the asteroid belt,” says Thomas Burbine (Mount Holyoke College), who was not involved in the study. “This potentially provides an opportunity to study samples from different parts of the belt to learn about the early solar system.”

    Future Studies

    Identifying asteroid families that are supplying asteroids to near-Earth space is the first step in linking meteorites found on Earth to asteroids in the main belt. Ultimately, studies like this one contribute to a better understanding of the early solar system.

    “We could have near-Earth asteroids and maybe even meteorite samples here on Earth that are from the Karma family,” says Burbine, “This family identification invites people to study these members and perhaps even collect spectral data in the future to try to match a meteorite sample.”

    While linking the composition of meteorites to asteroid families is difficult, future space missions could target families believed to supply near-Earth asteroids and even bring back samples.

    “Our study is a small piece of the big puzzle of understanding the early solar system that researchers are eager to solve,” says Novakovic.

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of Belgrade [Универзитет у Београду](RS)(CZ) is a public university in Serbia. It is the oldest and largest university in Serbia.
    The university was founded by Dositej Obradović, Serbian key figure in the Age of Enlightenment.

    Founded in 1808 as the Belgrade Higher School in revolutionary Serbia, by 1838 it merged with the Kragujevac-based departments into a single university. The University has around 97,700 enrolled students and over 4,800 members of academic staff. Since its founding, the University has educated more than 378,000 bachelors; around 25,100 magisters; 29,000 specialists; and 14,670 doctors. The University comprises 31 faculties; 12 research institutes, the university library, and 9 university centres. The faculties are organized into 4 groups: social sciences and humanities; medical sciences; natural sciences and mathematics; and technological sciences.

    19th century

    It was the highest ranking educational institution in Serbia between 1808 and 1905 as the first Higher School (1808–1813)- the Belgrade Lyceum, and the second Higher School (1863–1905). It was initially located at the Princess Ljubica’s Residence building and then moved to another significant site in Belgrade- the Captain Miša’s Mansion, today’s seat of the university.
    Dositej Obradović, founder of the university

    The second Higher School (also known as the Great School or Great Academy of Belgrade) was established as the successor of the Lyceum and was a combination of a classical gymnasium and a college, and as such developed into the University of Belgrade. Under the law, it was defined as a “scientific institute for higher and professional education”. The Minister of Education had control over this institution and it was managed by the Rector (elected by the monarch) and Academic Council.

    During its early history it had three departments: Philosophy, Engineering and Law. The Higher School formally became the University of Belgrade through the Law on the University from February 27, 1905. In addition to the Philosophy, Law and Electrical Engineering departments, this law introduced the Orthodox Theology and Medical schools.

    In the early 19th century, the studies of law lasted three years and the curriculum included comparative and state (constitutional) law; international law; criminal law and judicial procedure; as well as general subjects. This is how the modern legal education in Serbia emerged in the year 1808. Before enrolling the legal department, it was compulsory to graduate at the philosophy department where the studies lasted two years. So the legal studies lasted a total of five years. Since 1853, the legal education became independent from the studies of philosophy and from 1863 the legal education in Serbia lasted four years.

    The lectures were held by well-known professors who had earned their diplomas in Austria, Germany and France (Jovan Sterija Popović, Josif Pančić, Đura Daničić, and others).

    During the 1850s, the Philosophy (General) Department developed into a particular college. The University of Belgrade’s Faculty of Philosophy is today’s continuation of this department.

    The first academic lecture on electrical engineering in Serbia was held in 1894. Professor Stevan Marković was the first lecturer and founder of the Engineering Department at the Higher School. Only four years later, Professor Marković also established the first Serbian electrical engineering laboratory. Since then, this academic discipline has been studied at the Higher School and the University of Belgrade. The first diplomas in this field were given in 1922.

    20th century

    The University of Belgrade witnessed a massive growth and expansion in the years before the Second World War and especially after the founding of the second Yugoslavia. The first woman graduated from the University of Belgrade’s Law School in 1914.

    In the 1960s and 70s, the University developed into a remarkable regional and international educational institution. Many students from other countries were trained there. In the socialist Yugoslavia, the University was expanded, but it was also exposed to state and ideological influence. It has also been the driving force for the establishment of almost all other universities in today’s Serbia, Montenegro, North Macedonia and several universities in Bosnia and Herzegovina.

    In 1968, its students organized the first mass protest in post-World War II Yugoslavia.

    In the early 1990s the quality of university programs deteriorated as a consequence of the political instability in the country and the subsequent wars of Yugoslavia. There was a lack of financial resources and the quality dropped significantly. During the Milošević government in Serbia, the University had to face external political pressure and the lack of academic and administrative autonomy.

    In the mid-1990s, the University of Belgrade became an internationally recognized center of the political opposition in Serbia. Massive anti-government protests were staged by the Belgrade students and professors. The University’s student organizations (especially “Otpor!”) significantly contributed to overthrowing the government.

    21st century

    Since 2000, the University of Belgrade has taken important steps and has revitalized and improved the facilities and its teaching quality. There have been many reforms in higher education of the country. The University has made great efforts since then to improve the internal structure and has become a signatory of the Bologna declaration. Being one of Europe’s largest universities with an enrollment of nearly 90,000 students, the University broadly cooperates with international academic institutions and is involved in countless bilateral and multilateral academic projects.

     
  • richardmitnick 11:37 pm on February 15, 2021 Permalink | Reply
    Tags: "The Alignment of the Milky Way’s Entourage Explained", Astronomers have discovered dozens of dwarf galaxies orbiting our own mostly aligned along a thin sheet or plane with most of them orbiting the Milky Way in the same direction., , , , , Feedback in Realistic Environments (FIRE) computer simulation from Norhwestern University., If the simulated universe can make thin sheets of satellites then maybe there’s no problem with dark matter after all., Our galaxy’s satellite group is also a bit unusual: It’s dominated by the Large Magellanic Cloud (LMC)-a dwarf galaxy with 10 billion solar masses-about 10% of the Milky Way’s heft., Sky & Telescope, Some have argued that the plane's existence could challenge our current understanding of how dark matter helps galaxy systems form., Some think the Milky Way’s satellite sheet could last up to a billion years or so., The key seems to be the presence of a large satellite that dominates the small-galaxy attendants like the proverbial big fish in a small pond., The LMC might be bringing in some of its own satellites., The very existence of the Milky Way’s satellite sheet might challenge the current notion of dark matter.   

    From Sky & Telescope: “The Alignment of the Milky Way’s Entourage Explained” 

    From Sky & Telescope

    February 15, 2021
    Monica Young

    Astronomers are starting to understand why the dwarf galaxies around the Milky Way are aligned along a plane.

    Over the past couple decades, astronomers have discovered dozens of new dwarf galaxies orbiting our own. But as the numbers increased, it became apparent that something unexpected was happening. Rather than being distributed all the way around our galaxy, the satellites mostly align along a thin sheet, or plane, with most of them orbiting the Milky Way in the same direction. Picture them as pepperoni pre-emptively stuck on a thrown disc of pizza dough.

    The alignment surprised astronomers. Some thought the structure might not even be real, but new observations [Astronomy & Astrophysics] confirmed it’s really there. Meanwhile, others argued that the plane’s existence could challenge our current understanding of how dark matter helps galaxy systems form.

    Now, a more detailed look at the formation of galaxies and their dwarf entourages, to appear in the MNRAS, suggests that while the alignment is rare, it’s not completely unexpected. The key seems to be the presence of a large satellite that dominates the small-galaxy attendants like the proverbial big fish in a small pond.

    Blazing a Trail with FIRE

    1
    This Milky Way-mass galaxy comes from the universe constructed by the FIRE simulations.
    Credit: Latte Project.

    Graduate student Jenna Samuel (University of California, Davis) and colleagues approached the problem using the Feedback in Realistic Environments (FIRE) computer simulation [Northwestern University*]. While early cosmological simulations included only dark matter, which interacts primarily via gravity and is thus easier to model, FIRE includes interactions with baryons, aka the “normal” matter that makes stars and galaxies visible.

    Normal matter produces feedback that can counteract a galaxy’s gravity, such as supernovae and black hole jets, and including that feedback makes the artificial universe a little more realistic. As a result, the FIRE simulations has already helped solve some other controversies within the dark matter paradigm.

    Whether the Milky Way’s thin sheet of satellites fits in that paradigm remains debated, though. Similar structures are exceedingly rare in the universes simulated with only dark matter — so much so that the very existence of the Milky Way’s satellite sheet might challenge the current notion of dark matter.

    Samuel set out to see if that rarity persisted in the more realistic FIRE simulations. Selecting Milky Way-like galaxies and measuring the distribution of their satellites, she found that between 1 and 2% of these systems had satellites that fell along thin planes like our own galaxy’s. In other words, the phenomenon is rare but not outside the realm of possibility.

    “The fact that we’re finding any at all is still pretty surprising,” Samuel added at January’s American Astronomical Society meeting. If the simulated universe can make thin sheets of satellites, then maybe there’s no problem with dark matter after all.

    Most of those simulated structures were short-lived, though — they typically lasted less than 500 million years. Some think the Milky Way’s satellite sheet, on the other hand, could last up to a billion years or so.

    Big Fish in a Small Pond

    3
    The Large Magellanic Cloud (left) and the Small Magellanic Cloud (right) are small satellite systems of our Milky Way visible from the Southern Hemisphere. The LMC’s mass is 10% that of the Milky Way, making it a giant among dwarfs. Credit: Akira Fujii.

    But our galaxy’s satellite group is also a bit unusual: It’s dominated by the Large Magellanic Cloud (LMC), a dwarf galaxy with 10 billion solar masses, about 10% of the Milky Way’s heft. So Samuel rinsed and repeated, this time looking only at simulated galaxies with a giant dwarf among their satellites. When such a big fish influences the small pond, Samuel found that thin satellite planes were more common, occurring 7 to 16% of the time, and they lasted much longer, up to 3 billion years.

    The LMC might be bringing in some of its own satellites, Samuel speculates. In an earlier study [The Astrophysical Journal], Ekta Patel (University of California, Berkeley) and colleagues found the same when they reconstructed the orbital histories of 18 of Milky Way’s satellites using data from the European Space Agency’s Gaia mission.

    ESA (EU)/GAIA satellite .

    But Samuel thinks that the LMC also had an impact on the orbits of dwarf galaxies already around or coming in toward the Milky Way.

    “I agree with the Samuel study that the LMC plays a major role in the origin of the Milky Way’s plane of satellites and that the tension with cold dark matter will be resolved,” says Gurtina Besla (University of Arizona), who was not involved in the study. But she adds that there’s still work to be done to iron out the details and understand how the big-fish effect works. Her team is working on that problem, too, with more results coming soon.

    Incidentally, another prediction came out of the recent analysis of the FIRE simulations. Over the past decade, sweeping sky surveys have enabled the discovery of dwarf galaxies around our own. Samuel’s analysis shows that this survey is nearly complete — but not quite. She predicts that five additional satellites with more than 100,000 solar masses could still be discovered out to a million light-years from the Milky Way.

    *The FIRE project seeks to develop and explore cosmological simulations of galaxy formation that directly resolve the interstellar medium of individual galaxies while capturing their cosmological environment. FIRE aims to improve the predictive power of galaxy formation simulations by directly informing the implementation of sub-resolution processes with explicit small-scale models, thus reducing the reliance on adjustable model parameters.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

    Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

    Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

    “Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

     
  • richardmitnick 2:54 pm on February 4, 2021 Permalink | Reply
    Tags: "Planets and Comets Can't Hide from SOHO's Eye", , , , , ESA/NASA SOHO Solar Heliospheric Observatory, L1 is located 1.5 million kilometers inside Earth's orbit., , LASCO C1 went belly-up in 1998 after a bad command caused a loss of communication and other issues but C2 and C3 came through unscathed., Sky & Telescope, SOHO orbits near the first Lagrangian Point (L1) [See Langrange Point map provided]., SOHO's LASCO C3 coronagraph comprises three telescopes dubbed C1; C2; and C3 each of which employs an opaque occulting disk to block the Sun from view., With the help of the Solar Heliospheric Observatory you can not only keep track of the planets in the daytime sky but maybe even discover a comet.   

    From Sky & Telescope: “Planets and Comets Can’t Hide from SOHO’s Eye” 

    From Sky & Telescope

    February 3, 2021
    Bob King

    ESA/NASA SOHO.

    With the help of the Solar Heliospheric Observatory you can not only keep track of the planets in the daytime sky but maybe even discover a comet.

    1
    The Solar and Heliospheric Observatory can photograph rare events that can’t be seen from the ground, like this grouping of four planets and the Pleiades near the Sun that happened on May 15, 2000.
    Credit: ESA/NASA SOHO.

    Nature is replete with rhythms. Earth spins, planets revolve, variable stars pulsate, and the moon waxes and wanes. Many of us watched Jupiter and Saturn squeeze together during the recent Great Conjunction, then followed them until they disappeared in the solar glare in January.

    2
    SOHO’s LASCO C3 coronagraph made this photo of Jupiter and Saturn on January 26, 2021, when they were within 2° of the Sun. Horizontal lines through the planets, called pixel bleeding, are from overexposure. Cosmic rays from the Sun and other sources leave bright trails. Credit: ESA/NASA SOHO.

    Proximity to the Sun during solar conjunction temporarily interrupted our view of the planets. Broke the rhythm as it were. Saturn and Jupiter won’t return to visibility until the end of February at dawn. But why wait? I got on the web, dialed up the Solar and Heliospheric Observatory (SOHO) site, and watched each planet sidle up to the Sun during their transition from the evening to morning sky.

    3
    The Solar and Heliospheric Observatory keeps watch 24/7 on the Sun from its hovering post at the first Lagrangian Point. Other similarly stable Lagrangian Points are also shown. Not to scale.Credit: NOAA with SOHO; inset by ESA.

    Launched in December 1995, SOHO is a joint venture between NASA and the European Space Agency (ESA). It orbits near the first Lagrangian Point (L1), a region where the gravitational tugs of the Sun and Earth are at equilibrium, providing a ‘parking place’ for the spacecraft.

    LaGrange Points map. NASA.

    L1 is located 1.5 million kilometers inside Earth’s orbit, an ideal spot for SOHO to keep a continuous watch on our tempestuous star.

    Among its suite of instruments is the Large Angle and Spectrometric Coronagraph Experiment (LASCO) that comprises three telescopes dubbed C1, C2, and C3, each of which employs an opaque occulting disk to block the Sun from view.

    4
    ESA/NASA SOHO Large Angle and Spectrometric Coronagraph Experiment (LASCO).

    On Earth, the atmosphere scatters sunlight and makes the sky blue, but in airless space, the coronagraphs capture crisp views of the solar corona as well as coronal mass ejections — powerful eruptions of plasma that occur in the wake of solar flares and prominence ejections. They also record everything else crossing the field of view including stars, planets, asteroids, comets, and even a few deep-sky objects.

    LASCO C1 went belly-up in 1998 after a bad command caused a loss of communication and other issues, but C2 and C3 came through unscathed. LASCO C3 has a field of view about 16° across, equal to 45 million kilometers at the distance of the Sun, or half the diameter of Mercury’s orbit. The C2 coronagraph focuses in more narrowly; its field of view encompasses about 3°.

    5
    This diagram shows the paths of celestial objects that will cross the eye of the LASCO C2 and C3 coronagraphs in 2021. Each line or arc represents the path of a single object. Outer planets and stars always move from left to right across the view, while the inner planets Mercury and Venus can travel in both directions — from left to right when passing between the Earth and Sun and right to left when orbiting around the backside of the Sun. Credit: Worachate Boonplod.

    To anticipate what comes and goes under the coronagraphs’ gaze, Thai amateur astronomer and SOHO comet hunter Worachate Boonplod created a 2021 coronagraph transit calendar and list of events [see the full article if you are interested in this chart]. Each line in the image above represents the path of an object transiting either coronagraph’s field of view. Arrows indicate the direction of motion. Objects labeled 323P, 342P, and C/2020 S3 are comets. The limiting magnitude for the LASCO C3 instrument is about 8.0 – 8.5 and 8.5 – 9.0 for LASCO C2.

    A number of amateur astronomers routinely monitor SOHO images to find new comets in the Sun’s vicinity that are otherwise invisible in daylight from the ground. More than 4,100 have been discovered to date including 600+ by Boonplod. Most of them are Kreutz sungrazers, fragments of a much larger comet that broke up centuries ago that continue to orbit the Sun.

    To participate and potentially spot a new comet, check out The Official Guide to SOHO Comet Hunting or participate in The Sungrazer Project. If you regularly monitor the photos you’ll also be among the first to catch sight of coronal mass ejections, massive outbursts of solar plasma launched into space that can spark spectacular auroras.

    7
    February 1st was Saturn’s last day in the LASCO C3 field, but Jupiter remains in this C3 photo taken early on February 3rd, along with Iota (ι) (magnitude 4) and Upsilon (υ) Capricorni (magnitude 5).
    Credit: ESA/NASA SOHO.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

    Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

    Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

    “Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

     
  • richardmitnick 9:25 am on January 20, 2021 Permalink | Reply
    Tags: "Astronomy News- Galactic One-Two Punch; Black Hole Heartbeat Falters", , , , , Gaia-Enceladus globulars cluster, Sky & Telescope, Stellar-mass black hole in The system GRS 1915+105   

    From Sky & Telescope: “Astronomy News- Galactic One-Two Punch; Black Hole Heartbeat Falters” 

    From Sky & Telescope

    January 18, 2021
    Camille M. Carlisle

    In the news this week: Globular clusters have the detailed scoop on our galaxy’s past, and a “heartbeat” black hole binary in the Milky Way has gone mysteriously dim.

    Globular Clusters Reveal More Secrets of Milky Way’s Past

    The Milky Way may have endured a one-two punch from a pair of galaxies early in its history. A large fraction of the stars in our galaxy’s halo are crash debris, scraps from galactic collisions — including many of the ancient balls of stars called globulars clusters. Previous work has teased out which stars came in when, and how big their original host galaxies were. Astronomers think the largest offender was Gaia-Enceladus, which might have contributed more than 20 globulars.

    1
    This artist’s impression shows a computer-generated model of the Milky Way and accurate positions of globular clusters around it.Credit: NASA/ESA Hubble/L. Calçada.

    NASA/ESA Hubble Telescope.

    But intriguing new work by Jeremy Bailin and Ryker von Klar (University of Alabama, Tuscaloosa) suggests Gaia-Enceladus was a double whammy. Instead of assuming — as astronomers have been wont to do — that globulars’ current levels of heavy elements match what was in the gas that formed them, Bailin and von Klar accounted for how levels would have changed as stars within the clusters died and spread their remains around.

    They discovered that the globulars associated with Gaia-Enceladus split into two distinct chemical groups: There were two galaxies, not one. Maybe the pair were similar to the Large and Small Magellanic Clouds, which are on their first pass by the Milky Way and will someday merge with our galaxy, Bailin suggested during a poster presentation January 13th at the virtual winter meeting of the American Astronomical Society.

    X-ray Binary Plunges in Brightness Without Explanation

    A stellar-mass black hole slurping gas from a companion star has left astronomers baffled. The system, GRS 1915+105, is a well-known binary with a complex, comb-like pattern of X-ray variations. This variability likely arises due to outflows, in the form of winds and jets from the accreting black hole.

    But after more than two decades of consistent behavior, in 2018 the brightness of GRS 1915+105 dimmed, then plummeted in 2019. For reasons unknown, the X-rays coming from it dropped by a factor of 100, and its light curve became flatter and erratic. On September 9, 2019, it erupted in a bright flare.

    2
    The jagged light curve of GRS 1915+105 took a tumble in 2018 that it has yet to recover from. Credit: Joey Neilsen.

    Thanks to data from the NICER instrument aboard the International Space Station, Joey Neilsen (Villanova University) and colleagues used the flare’s spectrum to determine that the drop wasn’t due to the black hole ceasing to eat gas.

    NASA/NICER on the ISS.

    Rather, it’s due to something near the outer edge of the black hole’s gas disk blocking the view. A hefty wind might be blowing off the disk, or perhaps the disk’s structure has changed. As of Neilsen’s January 14th presentation, the system remains obscured. Although astronomers have seen temporary obscuration in several other systems, this is the longest-lasting example.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

    Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

    Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

    “Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

     
  • richardmitnick 9:48 pm on January 15, 2021 Permalink | Reply
    Tags: "Amateur Astronomer Finds “Lost” Moons of Jupiter", , , , , In a first an amateur astronomer has found four of five “lost” Jovian moons using images from a publicly available archive., , Sky & Telescope, The amateur who gave his name only as Kenneth found inspiration in two Minor Planet Electronic Circulars from November, The Minor Planet Center has now published circulars announcing three of the four “lost” moons.   

    From Sky & Telescope: “Amateur Astronomer Finds “Lost” Moons of Jupiter” 

    From Sky & Telescope

    January 11, 2021
    Jeff Hecht

    An amateur astronomer has recovered four of five “lost” Jovian moons.
    Update:

    The Minor Planet Center has now published circulars announcing three of the four “lost” moons:
    S/2003 J 23
    S/2003 J 12
    S/2003 J 4

    In a first, an amateur astronomer has found four of five “lost” Jovian moons using images from a publicly available archive. The feat allows a recalculation of their orbits, leaving only one of Jupiter’s 79 known satellites still missing.

    The formerly missing moons are among a group of 23 small (1 to 4 km) Jovian satellites that Scott Sheppard (Carnegie Institution for Science) and colleagues reported in 2003. Many of these were later lost, though some were later recovered; as of late November, five lost moons remained. They are so faint that large telescopes can see them for only about a month every year, when Jupiter is closest to Earth. Early observations were limited, leaving their initial orbits uncertain, too, all of which made them easy to lose as their predicted positions because ever-more inaccurate.

    1
    This diagram shows the initial orbits calculated for Jupiter’s “lost” moons vs. the newly calculated ones based on longer data baselines. While the differences in the calculated orbits appear small, they are significant when it comes to recovering the moons. Credit: Kenneth.

    On the Hunt for Lost Moons

    The amateur, who gave his name only as Kenneth, found inspiration in two Minor Planet Electronic Circulars from November, which reported recovery of two previously lost Jovian moons (S/2003 J 16 in MPEC 2020 V10 and S/2003 J 9 in MPEC 2020 V19). Those reports were submitted by professional astronomers, who found the moons in images dating from 2010 through 2018.

    To begin his quest to find other lost moons, Kenneth turned to the Canadian Astronomy Data Centre’s Solar System Object Image Search (SSOIS), where he found the best images of the small Jovian moons came from the same 3.6-meter Canada-France-Hawaii Telescope used to discover them.


    CFHT Telescope, Maunakea, Hawaii, USA, at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level.

    “I simply search on an object’s name and the page automatically displays a list of all the raw images that are supposed to contain the object,” he said. He started seeking the missing moons in images which covered the area where they should have been (according to their orbits) shortly before the first images used in their discoveries. He used that data to extend the moons’ orbits over longer time periods. With more orbital data, he could then hunt for additional images, and so on.

    With each raw image around 300 megabytes, Kenneth says tongue-in-cheek, “most time spent during moon hunting was simply waiting for the files to finish downloading.” But that was only the first step.

    Kenneth lined up sequential images using the World Coordinate System to help him match coordinates of reference stars. Then he spent up to several minutes blinking images, seeking objects that were moving from one frame to the next. The Aladin Sky Atlas helped him measure objects’ positions and movement, then he used Find_Orb software to calculate their orbits around Jupiter.

    His feat would not have been possible until recent years, says Sam Deen, another amateur astronomer who helped Kenneth and has done recovery work of his own. “The main resource we amateurs have nowadays is the sheer amount of data from the world’s largest telescopes [and] observatories taken every night for us to hunt through,” he adds.

    But while the data and analytical software are free and publicly available, that doesn’t mean it’s easy going. “The process is complicated, and the infrastructure isn’t always user-friendly,” Deen notes. Few amateurs use such resources now, but he asserts that anyone who puts in the time can do the same kind of work.

    Lost Moons Found

    On December 6th, Kenneth started looking for S/2003 J 23 because it had the least orbital uncertainty among the five missing moons. Over three days, he found additional observations between March and December in 2003 and also in February 2017.

    2
    This animation blinks two 300-second exposures. The bright streak in the first exposure comes from a bright satellite, but the moon is still clearly visible. Credit: CFHT / OSSOS / B. Gladman.

    Then he picked two targets he considered more interesting: Originally, S/2003 J 2 was thought to be the moon farthest from Jupiter and S/2003 J 12 was thought to be the innermost moon in a retrograde orbit. But the images Kenneth found revealed the orbits were more ordinary, putting them both in the Ananke group of retrograde moons. He needed 10 days to recover the fourth moon, S/2003 J 4. He has submitted these results to the Minor Planet Center for publication in their circular.

    3
    Images of lost moon S/2003 J 2, which appears at magnitude 24.5. Several background galaxies are also pictured.
    Credit: CFHT / OSSOS / B. Gladman.

    The fifth lost moon proved more difficult: Kenneth gave up seeking S/2003 J 10 after searching for more than a dozen days. The images he did find enabled him to plot its path over two months. That data suggests the little moon is part of the compact Carme group of irregular moons. But the uncertainty in the moon’s orbit is too large to predict where the moon is now.

    Meanwhile, unknown to Kenneth and most of the astronomical community, Sheppard had already recovered S/2003 J 2 and S/2003 J 23. But his submissions to the Minor Planet Center, along with Kenneth’s, are stuck in a processing backlog.

    Faint Needles in a Giant Haystack

    4
    A diagram of Jupiter’s 79 known satellites. The planet’s prograde moons (purple, blue) orbit relatively close to Jupiter while its retrograde moons (red) are farther out. (One exceptions is Valetudo, in green, a prograde-moving body that’s far out.)
    Credit: Carnegie Inst. for Science / Roberto Molar Candanosa.

    “It was impressive that Kenneth was able to use the older observations,” says Sheppard. Besides the moons being extremely faint, he notes that the 2001 data were not as good as the 2003 images used in the moons’ discovery.

    Faintness is not the only problem in tracking Jupiter’s small moons. Their orbits can extend up to 0.35 astronomical unit away from Jupiter (50 million kilometers, or about 5° in the sky), which means moons can be found across an area of about 80 square degrees. That’s a giant haystack to search for faint needles, especially when the required powerful telescopes have small fields of view.

    What makes the discoveries — and recoveries — worthwhile for Sheppard is not bragging rights, but what they teach us about planetary satellite systems and the history of the solar system.

    Most of Jupiter’s outer moons are small, with orbits that are retrograde (meaning they move around the planet in the opposite direction of its rotation), highly eccentric (long oval-shaped), and inclined to the plane of the solar system. The planet likely captured these moons long ago.

    Most of these moons belong to one of four distinct families, each of which contains one big object and many smaller ones. The smaller objects appear to be fragments, broken off during collisions with passing objects. While collisions are rare now, the number of small objects suggest there used to be many more. Finding and tracking new moons thus helps answer questions about the history of the solar system.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

    Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

    Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

    “Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

     
  • richardmitnick 10:41 pm on January 14, 2021 Permalink | Reply
    Tags: "China Opens World's Largest Radio Telescope to International Scientists", , , , , Five-hundred-meter Aperture Spherical Telescope (FAST), , Sky & Telescope   

    From Sky & Telescope: “China Opens World’s Largest Radio Telescope to International Scientists” 

    From Sky & Telescope

    January 13, 2021
    Andrew Jones

    China is making its Five-hundred-meter Aperture Spherical Telescope (FAST) available to international scientists in the wake of the collapse of the Arecibo telescope in Puerto Rico late last year.

    NAIC Arecibo Observatory operated by University of Central Florida, Yang Enterprises and UMET, Altitude 497 m (1,631 ft), which has now collapsed.

    FAST [Five-hundred-meter Aperture Spherical Telescope] radio telescope, with phased arrays from CSIRO engineers Australia located in the Dawodang depression in Pingtang County, Guizhou Province, South China.

    1
    This diagram represents a pulsar detected during FAST’s trial period. The telescope came fully online in January 2020.
    National Astronomical Observatories of China [国家天文台] at CAS [中国科学院](CN)

    The National Astronomical Observatories of China [国家天文台](NAOC)(CN), the telescope’s operator, confirmed on January 4th that scientists outside of China will be able to apply for time using the facility on April 1st. A timetable for observation will then be published by August 1st.

    Jiang Peng, FAST’s chief engineer, said about 10% of the observation time will be allocated to foreign scientists in the first year of the telescope’s opening to the global scientific community.

    The facility’s scientific committee also stated that FAST will become increasingly open to international teams. FAST’s collecting area and sensitivity are expected to make a range of contributions to radio astronomy and are therefore of great interest internationally.

    Also known as Tianyan, or the Eye of Heaven, FAST is the world’s largest single-dish telescope, situated in a karst depression in Pingtang, Guizhou province in southwest China. Nearby settlements were relocated to reduce electromagnetic emissions which could interfere with the telescope’s sensitive operations.

    FAST and Arecibo

    Like Arecibo, FAST’s receivers are suspended high above the dish. The dish itself consists of 4,450 triangular panels, which can be controlled by more than 2,000 mechanical winches. This allows researchers to maneuver to focus on different areas of the sky.

    With a deeper dish and panel system, FAST can cover a swath of sky within 40° of its zenith, while Arecibo was limited to 20°. However, unlike Arecibo, its receivers do not have radar capability, so it cannot investigate near-Earth objects.

    FAST is more than 2.5 times more sensitive than Arecibo, according to the National Astronomical Observatories, under the Chinese Academy of Sciences, which means that FAST can see fainter sources from farther away. FAST also has a greater effective collecting area (71,000 square meters), than the 305-meter-wide Arecibo (50,000 square meters).

    Wang Qiming, chief inspector of FAST’s operations and development center, told AFP in December, that he had visited Arecibo, which influenced China’s own plans.

    “We drew a lot of inspiration from its structure, which we gradually improved to build our telescope,” Wang said.

    The telescope began operations in September 2016 and officially entered service on January 11, 2020.


    Trial Operation for China’s FAST Telescope to End Soon

    FAST Possibilities

    FAST features an innovative 19-beam receiver developed by Chinese and Australian scientists that enables sensitive observations for a number of scientific goals.

    Researchers will be able to conduct studies and observations across a range of areas of interest, including pulsar discovery, galaxy evolution, and the large-scale nature of the universe. For example, FAST detected more than 240 pulsars and pulsar candidates by November 2020. These include an eclipsing binary millisecond pulsar in globular cluster Messier 92. The total number of pulsars FAST detects should reach 1,000 over the next five years, according to director of the FAST Science Committee, Wu Xiangping. Lists of detected pulsars can be found here, as well as those discovered through a Galactic Plane Pulsar Snapshot survey here.

    The giant facility has also contributed to the study of fast radio bursts (FRBs) and magnetars, and it has made observations for the Search for extraterrestrial intelligence (SETI), including microware surveys to look for weak space signals.

    FAST is also monitoring some of the pulsars it has detected to help find the signal of gravitational waves at nanohertz frequencies, joining efforts underway in the U.S., Europe, and Australia since 2005.

    The facility may also extend China’s deep-space exploration and communication capabilities to the edge of the solar system.

    “Although this telescope was built by the Chinese people, we should have the mind of a big country and contribute to the exploration of the mysteries of the universe.” Wu Xiangping said in November.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

    Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

    Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

    “Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

     
  • richardmitnick 9:51 am on October 31, 2020 Permalink | Reply
    Tags: "Astronomers Chart Star Formation History- Glimpse Fate of the Universe", , , , , , , , Sky & Telescope   

    From Sky & Telescope: “Astronomers Chart Star Formation History- Glimpse Fate of the Universe” 

    From Sky & Telescope

    October 26, 2020
    Monica Young

    Astronomers have tallied how star-making material evolved over cosmic time — and predicted how long stars will keep forming before the universe goes dark.

    1
    ALMA has captured a gold mine of galaxies in the Hubble Ultra Deep Field: Those rich in carbon monoxide gas (which traces molecular hydrogen) have lots of star-forming potential (colored orange). Those galaxies imaged solely by Hubble appear in blue. This image from the ALMA Spectroscopic Survey (ASPECS) covers one-sixth of the full Hubble Ultra Deep Field.
    Credit: B. Saxton (NRAO / AUI / NSF) / ALMA (ESO / NAOJ / NRAO) / NASA / ESA Hubble.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

    Astronomers have always been historians, looking back through time to piece together the story of the universe.

    Now, they have a new primary source in hand, a historical record of molecular hydrogen gas — the stuff that makes stars. The new observations enable not only a sweeping survey of the past, but a glimpse into our cosmic future.

    A History of Star Stuff

    Astronomers have spent decades charting the rise and fall of galaxies’ star formation over time. The stellar baby boom occurred about 10 billion years ago, at so-called “cosmic noon” [Annual Review of Astronomy & Astrophysics 2020]. During these early years of the universe, galaxies were bursting with newborn stars, sometimes birthing thousands per year. But rates have been falling ever since.

    To explore this rise and fall, astronomers went a step earlier in the process, charting not just the stars born but the material used to make them. Molecular hydrogen gas is cool enough that hydrogen atoms pair up — and it’s also cool enough to collapse into stars. Fabian Walter (Max Planck Institute for Astronomy, Germany) and colleagues used the Atacama Large Millimeter/submillimeter Array (ALMA) to survey the Hubble Ultra Deep Field (HUDF), one of the best-studied regions of the sky. The results of that survey appear in The Astrophysical Journal.


    ASPECS Project: ALMA and Hubble UDF

    ALMA is a 66-dish array in Chile capable of spying cool gas and dust in galaxies whose light has been traveling for up to 12 billion years. “This is one of the largest programs executed at ALMA,” Walter says, adding that the program used almost 200 hours of ALMA observing time. Along with other studies of the HUDF, ALMA provided the data Walter and colleagues needed to trace the flow of gas into galaxies and into stars.

    The gas that falls into galaxies is generally ionized, which means that the hydrogen atom is missing its electron. That gas has to cool, first recombining with electrons and then combining again into molecules, before it can form stars. Walter and colleagues are able to track both atomic and molecular gas to follow the flow of gas from the outermost reaches of a galaxy into its star-forming heart.

    “I think we already knew that’s how it has to work, but this paper nicely quantifies, perhaps for the first time, the global rate at which that happened, averaged over all galaxies, and over most of cosmic history,” says Mark Dickinson (NOAO), who was not involved in the study.

    3
    This diagram shows the flow of gas from the outermost reaches of a galaxy into its star-forming core. Feedback also occurs, tossing some gas back out again.Credit: Tumlinson et al. / Annual Reviews of Astronomy & Astrophysics 2018.

    The observations clearly show that galaxies never, at any one point in time, hold all the gas they need to make all their stars. The gas has to come from outside — the inflow of gas necessary for star formation has continued for all observed cosmic history.

    “Those are very challenging millimeter and radio measurements that were impossible not long ago,” Dickinson notes. “I think the Walter et al. paper sets an important benchmark for future analyses as new data are collected.”

    The Fate of the Universe

    As ever, examining the past also hints at the future. Star formation rates have declined ever since cosmic noon 10 billion years ago. The inflow of gas will only continue to decline, the researchers write: “The cosmic star formation rate density will continue its steady descent to the infinitesimal.”

    It’s a one-way street, Walter says: “I cannot think of a simple way to ‘reverse’ or ‘restart’ this trend.”

    The good news is that we have billions of years before the universe goes dark. And even as the influx of star-making material continues to decrease over the next 5 billion years, galaxies will continue making new stars with what they still receive. We’re hardly at the end of times just yet.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Sky & Telescope magazine, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

    Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

    Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

    “Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

     
  • richardmitnick 8:26 am on September 17, 2020 Permalink | Reply
    Tags: "Study Suggests Jupiter Could Have 600 Moons", , , , , Sky & Telescope,   

    From University of British Columbia CA via Sky & Telescope: “Study Suggests Jupiter Could Have 600 Moons” 

    U British Columbia bloc

    From University of British Columbia CA

    via

    From Sky & Telescope

    September 8, 2020
    Govert Schilling

    From University of British Columbia CA
    Edward Ashton
    Matthew Beaudoin
    Brett Gladman

    New detections of candidate moons suggest that the king of planets could have hundreds of smaller satellites.

    1
    Ganymede and Europa, the largest and smallest of Jupiter’s four Galilean moons, cast their shadows on Jupiter. The newly discovered detections reported here are evidence of much smaller moons in farther-out orbits.
    Credit: Damian Peach.

    Jupiter could have some 600 moons measuring at least 800 meters (2,600 feet) in diameter, according to a team of Canadian astronomers. They will present their findings on September 25th at the virtual Europlanet Science Congress 2020. Most of the moons are in wide, irregular, and retrograde orbits.

    Over the past 20 years, astronomers have found dozens of small Jovian moons thanks to the advance of large digital cameras. Back in 2003, Scott Sheppard (Carnegie Institution of Science) already estimated that the number of irregular moons larger than a kilometer would probably be around one hundred.

    Now, Edward Ashton, Matthew Beaudoin, and Brett Gladman (University of British Columbia, Vancouver) have detected about four dozen possible new Jovian moons that are even smaller. Extrapolating from the sky area they have searched (about one square degree), they conclude that there could be some 600 of these tiny objects orbiting the giant planet.

    The team studied 60 archival 140-second exposures of a field close to Jupiter, all of them taken within a 3-hour period on September 8, 2010, with the 340-megapixel MegaPrime camera at the Canada-France-Hawai‘i Telescope on Mauna Kea. The astronomers digitally combined the images in 126 different ways, one for every possible combination of speed and direction at which a potential Jovian moon might move across the sky.

    CFHT MegaPrime camera.


    CFHT Telescope, Maunakea, Hawaii, USA, at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level.

    2
    This discovery image shows one of the brightest new candidate moons (preliminary designation: j22r94a24). The new moon is at the center of the image; stars appear as streaks due to the shift-and-stack process used to combine multiple exposures.
    Edward Ashton (University of British Columbia CA).

    This method revealed 52 objects down to magnitude 25.7, corresponding to diameters of some 800 meters. Seven of the brighter finds turned out to be known irregular satellites of Jupiter; the others are almost certainly retrograde Jovian moons, which orbit the planet in the direction opposite its rotation. A paper describing the results has been accepted for publication in The Planetary Science Journal, The Population of Kilometer-scale Retrograde Jovian Irregular Moons.

    If this sensitive one-square-degree “pencil-beam” search already yields 45 formerly unknown moons, the researchers estimate that the total number of satellites within this size range must be around 600. The current official number of Jovian moons is 79.

    Sheppard (whose team found 20 new satellites of Saturn last year) is not surprised by the new result. “We used a similar shift and stack technique for our Jupiter moon discoveries that were announced in 2018,” he says. “In our paper, we also mentioned detections that we could not confirm as moons, because we didn’t observe them for the months and years required to reliably determine their orbits.”

    3
    This diagram shows the orbits of Jupiter’s 79 confirmed moons. The planet’s prograde moons (purple, blue) orbit relatively close to Jupiter while its retrograde moons (red) are farther out. The newly discovered moons likely belong to the latter group. (Valetudo, a previously discovered moon marked in green, is an exception; it’s farther out but orbits prograde.) Credit: Carnegie Inst. for Science / Roberto Molar Candanosa.

    Likewise, the Canadian team cannot yet claim new discoveries for their 45 new detections, let alone for the extrapolated 600. “It takes a lot of large telescope time to get reliable orbits for these very small and numerous moons,” says Sheppard, “so one has to decide if that is scientifically valuable.”

    According to Ashton, there are currently no plans for follow-up observations of the new moons. “It would be nice to confirm them,” he says, “but there is no way to track them without starting from scratch.” However, the tiny moons will certainly be found again by future instruments like the Vera C. Rubin Observatory.

    Vera C. Rubin Observatory Telescope currently under construction on the El Peñón peak at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes, altitude 2,715 m (8,907 ft).

    “They will then be linked back, so our observations will eventually be incorporated.”

    The new detections raise the question of how small an object can be and still be called a moon. “Eventually one descends to ring particles, and some kind of cutoff will be useful,” says Ashton. But Sheppard doesn’t believe we need “any more definition of what is a moon.” Anyway, he says, the International Astronomical Union will not name planetary moons smaller than one kilometer in size.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Sky & Telescope magazine, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

    Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

    Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

    “Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

    U British Columbia Campus

    The University of British Columbia CA is a global centre for research and teaching, consistently ranked among the 40 best universities in the world. Since 1915, UBC’s West Coast spirit has embraced innovation and challenged the status quo. Its entrepreneurial perspective encourages students, staff and faculty to challenge convention, lead discovery and explore new ways of learning. At UBC, bold thinking is given a place to develop into ideas that can change the world.

     
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