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  • richardmitnick 10:53 am on July 3, 2020 Permalink | Reply
    Tags: "Measuring the Structure of a Giant Solar Flare", , Solar research   

    From Harvard-Smithsonian Center for Astrophysics: “Measuring the Structure of a Giant Solar Flare” 

    Harvard Smithsonian Center for Astrophysics


    From Harvard-Smithsonian Center for Astrophysics

    1
    An ultraviolet image of a giant solar flare on 2017-09-10 as seen by SDO, the Solar Dynamics Observatory.

    NASA SDO

    White contours show the magnetic field lines derived from models; the red regions show the high resolution microwave images from the Expanded Owens Valley Solar Array (EOVSA) that reveal the fast-rising, balloon-shaped, erupting hot gas (the scale shows the frequency of the observations).

    15 radio telescopes of NJIT Owens Valley Solar Array, near Big Pine, California, USA, Altitude 1,200 m (3,900 ft)


    These high spatial resolution images have enabled astronomers top confirm that these regions are the primary locations for accelerating and channeling the fast-moving electrons into interplanetary space. Credit:NSF, NASA, and Chen et al. 2020

    The sun’s corona, its hot outermost layer, has a temperature of over a million degrees Kelvin, and produces a wind of charged particles, about one-millionth of the moon’s mass is ejected each year. Transient events have been known to cause large eruptions of high-energy charged particles into space, some of which bombard the Earth, producing auroral glows and occasionally veven disrupting global communications. One issue that has long puzzled astronomers is how the sun produces these high-energy particles.

    Flares or other kinds of impulsive events are thought to be key mechanisms. The hot gas is ionized and produces an underlying sheet of circulating current that generates powerful magnetic field loops. When these loops twist and break they can abruptly eject pulses of charged particles. In the standard picture of solar flares, large-scale motions drive this activity, but where and how the energy is released locally, and how the particles are accelerated, have remained uncertain because the magnetic properties of the large-scale current sheet have not been measured at sizes small enough to correspond to the domains of flaring activity.

    CfA astronomers Chengcai Shen, Katharine Reeves and a team of their collaborators report spatially resolved observations of the regions of magnetic field and flare-ejected electron activity. The team used the thirteen antenna array at the Expanded Owens Valley Solar Array (EOVSA) and its microwave imaging techniques to observe the giant solar flare on 2017 September 10. As the event progressed they saw a rapidly ascending, balloon-shaped dark cavity, corresponding to twisted magnetic field lines rising, breaking, and ejecting electrons as viewed roughly along the axis of the field lines. The scientists were able to model the details of the configuration, and by estimating the strength of the magnetic field and the speed of the plasma flow, they determined that this one large flare alone released during its peak few minutes about .02% of the energy of the entire sun. Their results suggest that these kinds of spatial structures in the field are the primary locations for accelerating and channeling the fast-moving electrons into interplanetary space, and demonstrate the power of these new, spatially resolved imaging techniques.

    Science paper:
    “Measurement of Magnetic Field and Relativistic Electrons Along a Solar Flare Current Sheet”
    Nature Astronomy

    See the full article here .


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    Please help promote STEM in your local schools.

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    The Center for Astrophysics combines the resources and research facilities of the Harvard College Observatory and the Smithsonian Astrophysical Observatory under a single director to pursue studies of those basic physical processes that determine the nature and evolution of the universe. The Smithsonian Astrophysical Observatory (SAO) is a bureau of the Smithsonian Institution, founded in 1890. The Harvard College Observatory (HCO), founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University, and provides facilities and substantial other support for teaching activities of the Department of Astronomy.

     
  • richardmitnick 9:54 am on June 30, 2020 Permalink | Reply
    Tags: "Solar Orbiter ready for science despite COVID-19 setbacks", , Solar research   

    From United Space in Europe: “Solar Orbiter ready for science despite COVID-19 setbacks” 

    ESA Space For Europe Banner

    From European Space Agency – United space in Europe

    From United Space in Europe

    1

    ESA’s Solar Orbiter has successfully completed four months of painstaking technical verification, known as commissioning. Despite the challenges imposed by the COVID-19 pandemic, the spacecraft is now ready to begin performing science as it continues its cruise towards the Sun.

    When Solar Obiter blasted into space on an Atlas V rocket from Cape Canaveral, Florida, on 10 February, the teams behind the €1.5 billion mission did not anticipate that within weeks, the spread of COVID-19 would evict them from their high-tech control rooms, making the challenging process of commissioning the spacecraft’s instruments even harder.

    In normal circumstances, many of the project’s scientists and engineers would have gathered at the European Space Operations Centre (ESOC) in Darmstadt, Germany. Together, they would have worked in close cooperation with the spacecraft operators, to bring the spacecraft and its instruments to life.

    This happened more or less as usual during the most challenging early weeks of Solar Orbiter’s in-orbit existence, but when the instrument teams were invited to ESOC in March, the situation in Europe was rapidly changing.

    Each of the ten instrument teams needed many representatives on site. Two or three from each team were allowed in a dedicated Solar Orbiter control room. “The other representatives worked from a dedicated support area,” says Sylvain Lodiot, ESA’s Solar Orbiter Spacecraft Operations Manager. It was not unusual to have 15 or more people in the main control room working too. But within a week, it became clear that European countries were heading into lockdown and so the external teams were asked to return home.

    The Italian-German-Czech team behind the METIS coronograph, an instrument measuring the visible, ultraviolet and extreme ultraviolet emissions of the solar corona in unprecedented temporal and spatial resolution, was just getting ready to switch on the instrument for the first time when the decision was made that people from that time coronavirus hotspots in Italian regions Piemonte and Lombardy were no longer allowed to enter ESOC for safety reasons.

    “We had a hard time in trying to re-arrange the team skills on the fly with those who could enter,” says Marco Romoli, METIS principle investigator. “And thanks to ESOC people and to the steady nerves of those present, we were able to successfully complete the activity.”

    The situation became even more serious when several workers at ESOC tested positive for the virus, and the site effectively closed.

    The COVID lockdown

    2
    SWA principal investigator Chris Owen turn his two-year-old son’s playroom into an improvised control room.

    “We had to protect the people,” says Sylvain, whose last task before going home was to switch off all the instruments on Solar Orbiter. “It felt horrible because I didn’t know when those instruments were coming back online,” he says.

    In the event, it was only about a week later that a skeleton staff returned and with full social distancing measures in place began working remotely with the instrument teams to get the commissioning done.

    One of the instrument teams most affected was the Solar Wind Analyser (SWA) team. The solar wind, which is constantly released from the Sun, is composed of a mixture of electrically charged particles called ions, and electrons. The SWA instrument comprises three different sensors to measure the fluxes and composition of these various particle populations. Each sensor operates as a kind of ‘electrical periscope’ that uses high voltages, up to 30 kilovolts in one case, to divert the solar wind particles into the detector.

    To operate those high voltages safely, the team had planned not to turn on the instrument until at least a month after launch. This was intended so no traces of Earth’s atmosphere would remain within the SWA sensors. If there were, these high voltages could cause arcing and damage the sensors.

    The switch on process for each of the SWA detectors is long because each high-voltage subsystem must be powered up in steps of just 20 or 50 volts at a time. After each increase, the instrument is checked to make sure nothing untoward has happened.

    When SWA’s principal investigator Christopher Owen, of the Mullard Space Science Laboratory, University College London (MSSL/UCL), had left Germany, he and his team had begun to make plans to commission the instrument from their lab in the UK. But then the UK lockdown was announced, meaning a move to working from the home office for almost everybody.

    “When I left the lab, I grabbed a couple of laptops and four screens, and brought them home. I then evicted my two-year-old from his nursery and set everything up in there,” says Christopher. And from this temporary control centre, once ESOC had returned to work, he worked remotely with the rest of the SWA team and the skeleton staff in Darmstadt to get the instrument commissioned.

    “We had serious doubts about whether we could work like this,” says Sylvain about the process in general, “but we adapted and in the end, it worked very well because the team all knew each other.”

    Ready for science


    Solar Orbiter’s first close approach to the Sun. On 15 June 2020, Solar Orbiter made its first close approach to the Sun, getting as close as 77 million kilometres to the star’s surface.

    The other instrument teams also successfully finished their commissioning. “This is undoubtedly the first mission whose instruments were completely commissioned from people’s homes,” says David Berghmans, from the Royal Observatory of Belgium, Brussels, Belgium, and principal investigator of the Extreme Ultraviolet Imager (EUI).

    Not only did the job get done, but they made up for lost time and managed to complete their commissioning on the original timeline. “Even in a normal world I would be very happy with where we are now,” says Daniel Müller, Solar Orbiter Project Scientist at ESA, “I never expected that almost everything would work flawlessly out of the box.”

    That’s testimony to the expertise with which the spacecraft was made by the prime contractor Airbus DS (UK) and its instruments were made by the various instrument teams. On 25 June, the Solar Orbiter Review Board endorsed this achievement by declaring the Mission Commissioning Results Review successful.

    For César García Marirrodriga, ESA’s Solar Orbiter’s Project Manager, it was a big moment because with commissioning over, his job is done and he hands over the spacecraft to the mission operations manager. “I’m very happy to hand it over because I know it is going in the right direction,” says César.

    And for Daniel, it is a big moment too because now the mission is ready to perform science. “In these four months since launch, the 10 instruments onboard have been carefully checked and calibrated one by one, like tuning individual musical instruments. And now it is time for them to perform together,” he says.

    This month’s ‘remote-sensing checkout window’ from 17 to 22 June presented the first opportunity to have all the instruments play together. Receiving the recordings from the spacecraft, which is currently more than 160 million kilometres away, will be completed in the next few days.

    “We’re very excited about this first ‘concert’. For the first time, we will be able to put together the images from all our telescopes and see how they take complementary data of the various parts of the Sun including the surface; the outer atmosphere, or corona; and the wider heliosphere around it. This is what the mission was built for,” says Daniel. These first light images will be released to the public in mid-July.

    100 days worth of data

    3
    The team behind Solar Orbiter’s magnetometer in a Zoom meeting while running experiments on the instrument amid the COVID-19 lockdown.

    Other instruments are already collecting data too. In the case of the Magnetometer (MAG), this was first switched on just a day after launch. “We got just under 100 days’ worth of data through the commissioning period, and it’s wonderful data,” says Helen O’Brien, from Imperial College and MAG’s chief engineer.

    MAG was switched on early so that it could take readings as it was carried away from the spacecraft as its boom arm was deployed. “The instrument behaved beautifully. It was wonderful to see the field decay as we moved away from the spacecraft,” says Helen.

    That data will allow the team to understand the magnetic field being generated by the spacecraft itself, so that they can now remove it from their science data to leave just the magnetic field being carried into space away from the Sun. And there is plenty of data already. The team already has more than two billion scientific measurements to analyse. “The data is outstanding, really, really good, so we’re very happy,” says Tim Horbury, Imperial College, UK, and principal investigator for the instrument.

    The mission now continues on course to the Sun. During this cruise phase, the spacecraft’s in-situ instruments will gather scientific data about the environment around the spacecraft, while the remote-sensing instruments will be fine-tuned by the teams in preparation for science operations in closer vicinity of the Sun. The cruise phase lasts until November 2021, after which Solar Orbiter will begin the science phase of its mission.

    [NOTES FOR EDITORS]
    Solar Orbiter is an ESA-led mission with strong NASA participation. Twelve ESA member states including UK, Belgium, Germany, France, Italy, Spain, Czech Republic, Switzerland, Poland, Sweden, Austria and Norway participate in the mission. The prime contractor is Airbus Defence and Space in Stevenage, UK. Solar Orbiter is the first ‘medium’-class mission implemented in the Cosmic Vision 2015-25 programme, the current planning cycle for ESA’s space science missions. The total mission cost estimate of about €1.5 billion includes spacecraft and payload manufacturing and development, launcher services provided by NASA, as well as flight operations over the nominal and extended life span of 10 years.

    Solar Orbiter’s suite of ten science instruments that will study the Sun. There are two types: in situ and remote sensing. The in situ instruments measure the conditions around the spacecraft itself. The remote-sensing instruments measure what is happening at large distances away. Together, both sets of data can be used to piece together a more complete picture of what is happening in the Sun’s corona and the solar wind.

    The in situ instruments:

    EPD: Energetic Particle Detector
    EPD will measure the energetic particles that flow past the spacecraft. It will look at their composition and variation in time. The data will help scientists investigate the sources, acceleration mechanisms, and transport processes of these particles. Principal Investigator: Javier Rodríguez-Pacheco, University of Alcalá, Spain

    MAG: Magnetometer
    MAG will measure the magnetic field around the spacecraft with high precision. It will help determine how the Sun’s magnetic field links to the rest of the Solar System and changes with time. This will help us understand how the corona is heated and how energy is transported in the solar wind. Principal Investigator: Tim Horbury, Imperial College London, United Kingdom

    RPW: Radio and Plasma Waves
    RPW will measure the variation in magnetic and electric fields using a number of sensors and antennas. This will help to determine the characteristics of electromagnetic waves and fields in the solar wind. RPW is the only instrument on Solar Orbiter that makes both in situ and remote sensing measurements. Principal Investigator: Milan Maksimovic, LESIA, Observatoire de Paris, France

    SWA: Solar Wind Plasma Analyser
    SWA consists of a suite of sensors that will measure the solar wind’s bulk properties, such as density, velocity and temperature. It will also measure the composition of the solar wind. Principal Investigator: Christopher Owen, Mullard Space Science Laboratory, United Kingdom

    The remote-sensing instruments:

    EUI: Extreme Ultraviolet Imager
    EUI will take images of the solar chromosphere, transition region and corona. This will allow scientists to investigate the mysterious heating processes that take effect in this region and will allow connecting in situ measurements of the solar wind back to their source regions on the Sun. Principal Investigator: David Berghmans, Royal Observatory, Belgium

    Metis: Coronagraph
    Metis will take simultaneous images of the corona in visible and ultraviolet wavelengths. This will show the structure and dynamics of the solar atmosphere in unprecedented detail, stretching out from 1.7 to 4.1 solar radii. This will allow scientists to look for the link between the behaviour of these regions and space weather in the inner Solar System.
    Principal Investigator: Marco Romoli, INAF – University of Florence, Italy

    PHI: Polarimetric and Helioseismic Imager
    PHI will provide high-resolution measurements of the magnetic field across the photosphere, and maps of its brightness at visible wavelengths. It will also produce velocity maps of the movement of the photosphere that will allow helioseismic investigations of the solar interior, in particular the convective zone. Principal Investigator: Sami Solanki, Max-Planck-Institut für Sonnensystemforschung, Germany

    SoloHI: Heliospheric Imager
    SoloHI will take images of the solar wind by capturing the light scattered by electrons particles in the wind. This will allow the identification of transient disturbances in the solar wind, such as the type that can trigger a coronal mass ejection, in which a billion tons of coronal gas can be ejected outwards into space.
    Principal Investigator: Russell A. Howard, US Naval Research Laboratory, Washington, D.C., USA

    SPICE: Spectral Imaging of the Coronal Environment
    SPICE will reveal the properties of the solar transition region and corona by measuring the extreme ultraviolet wavelengths given off by the plasma. This data will be matched to the solar wind properties that are subsequently detected by the spacecraft’s in situ instruments. European-led facility instrument; Principal Investigator for Operations Phase: Frédéric Auchère, IAS, Orsay, France

    STIX: X-ray Spectrometer/Telescope
    STIX will detect X-ray emission coming from the Sun. This could be from hot plasma, often related to explosive magnetic activity such as solar flares. STIX will provide the timing, location, intensity, and energy data for these events so that their effects on the solar wind can be better understood. Principal Investigator: Säm Krucker, FHNW, Windisch, Switzerland

    Solar Orbiter is a space mission of international collaboration between ESA and NASA. Its mission is to perform unprecedented close-up observations of the Sun and from high-latitudes, providing the first images of the uncharted polar regions of the Sun, and investigating the Sun-Earth connection. Data from the spacecraft’s suite of ten instruments will provide unprecedented insight into how our parent star works in terms of the 11-year solar cycle, and how we can better predict periods of stormy space weather.

    ESA-S.Poletti

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The European Space Agency (ESA), 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.

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  • richardmitnick 1:04 pm on June 25, 2020 Permalink | Reply
    Tags: "Physicists spot a new class of neutrinos from the sun", , , , Borexino Collaboration, , , , Solar research   

    From Science News: “Physicists spot a new class of neutrinos from the sun” 

    From Science News

    June 24, 2020
    Emily Conover

    1
    Neutrinos from the sun’s second-most prominent nuclear fusion process have been spotted in the Borexino detector (inside shown with light-detecting sensors). Borexino Collaboration

    Neutrinos spit out by the main processes that power the sun are finally accounted for, physicists report.

    Two sets of nuclear fusion reactions predominate in the sun’s core and both produce the lightweight subatomic particles in abundance. Scientists had previously detected neutrinos from the most prevalent process. Now, for the first time, neutrinos from the second set of reactions have been spotted, researchers with the Borexino experiment said June 23 in a talk at the Neutrino 2020 virtual meeting.

    “With this outcome, Borexino has completely unraveled the two processes powering the sun,” said physicist Gioacchino Ranucci of Italy’s National Institute for Nuclear Physics in Milan.

    In the sun’s core, hydrogen fuses into helium in two ways. One, known as the proton-proton chain, is the source of about 99 percent of the star’s energy. The other group of fusion reactions is the CNO cycle, for carbon, nitrogen and oxygen — elements that allow the reactions to proceed. Borexino had previously spotted neutrinos from the proton-proton chain (SN: 9/1/14). But until now, neutrinos from the CNO cycle were MIA.

    “They’re top of everybody’s list to try and identify and to spot,” says physicist Malcolm Fairbairn of King’s College London. “Now they think they’ve spotted them, which is a major achievement, really an extremely difficult measurement to make.”

    Located deep underground at the Gran Sasso National Laboratory in Italy, Borexino searches for flashes of light produced as neutrinos knock into electrons in a large vat of liquid.

    Gran Sasso LABORATORI NAZIONALI del GRAN SASSO, located in the Abruzzo region of central Italy

    INFN/Borexino Solar Neutrino detector, at Laboratori Nazionali del Gran Sasso, situated below Gran Sasso mountain in Italy

    Researchers have spent years fine-tuning the experiment to detect the elusive neutrinos that herald the CNO cycle. Although difficult to observe, the particles are plentiful, Borexino confirmed. On Earth, around 700 million neutrinos from the sun’s CNO cycle pass through a square centimeter each second, the researchers report.

    The result, presented for the first time at the virtual meeting, must still clear the hurdle of peer review in a scientific journal before it is fully official.

    Studying these particles could help reveal how much of the sun is composed of elements heavier than hydrogen and helium, a property known as metallicity. That’s because the rate at which CNO cycle neutrinos are produced depends on the sun’s content of carbon, nitrogen and oxygen. Different types of measurements currently disagree about the sun’s metallicity, with one technique suggesting higher metallicity than another. In the future, more sensitive measurements of CNO neutrinos could help scientists disentangle the problem.

    The CNO cycle is even more important in stars heavier than the sun, where it is the main fusion process. Studying this cycle in the sun can help physicists understand the inner workings of other stars, says Zara Bagdasarian, a physicist at the University of California, Berkeley and a member of the Borexino Collaboration. “It’s very important for us to understand how the sun works.”

    See the full article here .


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  • richardmitnick 8:39 am on June 16, 2020 Permalink | Reply
    Tags: "Solar Orbiter makes first close approach to the Sun", ESA's Sun-explorer Solar Orbiter reached its first perihelion- the point in its orbit closest to the star- on 15 June 2020 getting as close as 77 million kilometres to the star's surface., , Solar research   

    From European Space Agency – United Space in Europe: “Solar Orbiter makes first close approach to the Sun” 

    ESA Space For Europe Banner

    From European Space Agency – United Space in Europe

    6.15.20

    1
    ESA’s Sun-explorer Solar Orbiter reached its first perihelion, the point in its orbit closest to the star, on 15 June 2020, getting as close as 77 million kilometres to the star’s surface.

    ESA’s Sun-exploring mission Solar Orbiter has made its first close approach to the star on June 15, getting as close as 77 million kilometres to its surface, about half the distance between the Sun and Earth.

    In the week following this first perihelion, the point in the orbit closest to the Sun, the mission scientists will test the spacecraft’s ten science instruments, including the six telescopes on-board, which will acquire close-up images of the Sun in unison for the first time. According to ESA’s Solar Orbiter Project Scientist Daniel Müller, the images, to be released in mid-July, will be the closest images of the Sun ever captured.

    “We have never taken pictures of the Sun from a closer distance than this,” Daniel says. “There have been higher resolution close-ups, e.g. taken by the four-meter Daniel K. Inouye Solar Telescope in Hawaii earlier this year.

    Daniel K. Inouye Solar Telescope, DKIST, atop the Haleakala volcano on the Pacific island of Maui, Hawaii, USA, at an altitude of 3,084 m (10,118 ft).

    But from Earth, with the atmosphere between the telescope and the Sun, you can only see a small part of the solar spectrum that you can see from space.”

    NASA’s Parker Solar Probe, launched in 2018, makes closer approaches. The spacecraft, however, doesn’t carry telescopes capable of looking directly at the Sun.

    NASA Parker Solar Probe Plus named to honor Pioneering Physicist Eugene Parker

    “Our ultraviolet imaging telescopes have the same spatial resolution as those of NASA’s Solar Dynamic Observatory (SDO), which takes high-resolution images of the Sun from an orbit close to Earth.

    NASA/SDO

    Because we are currently at half the distance to the Sun, our images have twice SDO’s resolution during this perihelion,” says Daniel.

    The primary objective of these early observations is to prove that Solar Orbiter’s telescopes are ready for future scientific observations.

    “For the first time, we will be able to put together the images from all our telescopes and see how they take complementary data of the various parts of the Sun including the surface, the outer atmosphere, or corona, and the wider heliosphere around it,” says Daniel.


    Solar Orbiter’s first close approach to the Sun

    The scientists will also analyse data from the four in-situ instruments that measure properties of the environment around the spacecraft, such as the magnetic field and the particles making up the solar wind.

    “This is the first time that our in-situ instruments operate at such a close distance to the Sun, providing us with a unique insight into the structure and composition of the solar wind,” says Yannis Zouganelis, ESA’s Solar Orbiter Deputy Project Scientist. “For the in-situ instruments, this is not just a test, we are expecting new and exciting results.”

    Solar Orbiter, launched on 10 February this year, is completing its commissioning phase on 15 June and will commence its cruise phase, which will last until November 2021. During the main science phase that follows, the spacecraft will get as close as 42 million kilometres to the Sun’s surface, which is closer than the planet Mercury.

    The spacecraft will reach its next perihelion in early 2021. During the first close approach of the main science phase, in early 2022, it will get as close as 48 million kilometres.


    Solar Orbiter’s journey around the Sun. Solar Orbiter will use several gravity-assist maneuvres at Venus to shift its orbit out of the ecliptic plane to be able to look at the Sun’s poles.

    Solar Orbiter operators will then use the gravity of Venus to gradually shift the spacecraft’s orbit out of the ecliptic plane, in which the planets of the Solar System orbit. These fly-by manoeuvres will enable Solar Orbiter to look at the Sun from higher latitudes and get the first ever proper view of its poles. Studying the activity in the polar regions will help the scientists to better understand the behaviour of the Sun’s magnetic field, which drives the creation of the solar wind that in turn affects the environment of the entire Solar System.

    Since the spacecraft is currently 134 million kilometres from Earth, it will take about a week for all perihelion images to be downloaded via ESA’s 35-m deep-space antenna in Malargüe, Argentina. The science teams will then process the images before releasing them to the public in mid-July. The data from the in-situ instruments will become public later this year after a careful calibration of all individual sensors.

    “We have a nine-hour download window every day but we are already very far from Earth so the data rate is much lower than it was in the early weeks of the mission when we were still very close to Earth,” says Daniel. “In the later phases of the mission, it will occasionally take up to several months to download all the data because Solar Orbiter really is a deep space mission. Unlike near-Earth missions, we can store a lot of data on-board and downlink it when we are closer to home again and the data connection is much better.”

    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 European Space Agency (ESA), 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.

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  • richardmitnick 12:42 pm on April 19, 2020 Permalink | Reply
    Tags: "New research helps explain why the solar wind is hotter than expected", , , , , Solar research,   

    From University of Wisconsin Madison: “New research helps explain why the solar wind is hotter than expected” 

    From University of Wisconsin Madison

    April 14, 2020
    Sarah Perdue
    saperdue@wisc.edu

    When a fire extinguisher is opened, the compressed carbon dioxide forms ice crystals around the nozzle, providing a visual example of the physics principle that gases and plasmas cool as they expand. When our sun expels plasma in the form of solar wind, the wind also cools as it expands through space — but not nearly as much as the laws of physics would predict.

    In a study published April 14 in the Proceedings of the National Academy of Sciences, University of Wisconsin–Madison physicists provide an explanation for the discrepancy in solar wind temperature. Their findings suggest ways to study solar wind phenomena in research labs and learn about solar wind properties in other star systems.

    “People have been studying the solar wind since its discovery in 1959, but there are many important properties of this plasma which are still not well understood,” says Stas Boldyrev, professor of physics and lead author of the study. “Initially, researchers thought the solar wind has to cool down very rapidly as it expands from the sun, but satellite measurements show that as it reaches the Earth, its temperature is 10 times larger than expected. So, a fundamental question is: Why doesn’t it cool down?”

    1
    The solar wind causes events such auroras, like this one photographed by a U.S. astronaut after docking with the International Space Station. It can also interfere with satellite communications and distort the magnetic field of earth. NASA photo.

    Solar plasma is a molten mix of negatively charged electrons and positively charged ions. Because of this charge, solar plasma is influenced by magnetic fields that extend into space, generated underneath the solar surface. As the hot plasma escapes from the sun’s outermost atmosphere, its corona, it flows through space as solar wind. The electrons in the plasma are much lighter particles than the ions, so they move about 40 times faster.

    With more negatively charged electrons streaming away, the sun takes on a positive charge. This makes it harder for the electrons to escape the sun’s pull. Some electrons have a lot of energy and keep traveling for infinite distances. Those with less energy can’t escape the sun’s positive charge and are attracted back to the sun. As they do, some of those electrons can be knocked off their tracks ever-so-slightly by collisions with surrounding plasma.

    “There is a fundamental dynamical phenomenon that says that particles whose velocity is not well aligned with the magnetic field lines are not able to move into a region of a strong magnetic field,” Boldyrev says. “Such returning electrons are reflected so that they stream away from the sun, but again they cannot escape because of the attractive electric force of the sun. So, their destiny is to bounce back and forth, creating a large population of so-called trapped electrons.”

    In an effort to explain the temperature observations in the solar wind, Boldyrev and his colleagues, UW–Madison physics professors Cary Forest and Jan Egedal looked to a related, but distinct, field of plasma physics for a possible explanation.

    Around the time scientists discovered solar wind, plasma fusion researchers were thinking of ways to confine plasma. They developed “mirror machines,” or plasma-filled magnetic field lines shaped as tubes with pinched ends, like bottles with open necks on either end.

    As charged particles in the plasma travel along the field lines, they reach the bottleneck and the magnetic field lines are pinched. The pinch acts as a mirror, reflecting particles back into the machine.

    “But some particles can escape, and when they do, they stream along expanding magnetic field lines outside the bottle. Because the physicists want to keep this plasma very hot, they want to figure out how the temperature of the electrons that escape the bottle declines outside this opening,” Boldyrev says. “It’s very similar to what’s happening in the solar wind that expands away from the sun.”

    Boldyrev and colleagues thought they could apply the same theory from the mirror machines to the solar wind, looking at the differences in the trapped particles and those that escape. In mirror machine studies, the physicists found that the very hot electrons escaping the bottle were able to distribute their heat energy slowly to the trapped electrons.

    “In the solar wind, the hot electrons stream from the sun to very large distances, losing their energy very slowly and distributing it to the trapped population,” Boldyrev says. “It turns out that our results agree very well with measurements of the temperature profile of the solar wind and they may explain why the electron temperature declines with the distance so slowly,” Boldyrev says.

    The accuracy with which mirror machine theory predicts solar wind temperature opens the door for using the machines to study solar wind in laboratory settings.

    “Maybe we’ll even find some interesting phenomena in those experiments that space scientists will then try to look for in the solar wind,” Boldyrev says. “It’s always fun when you start doing something new. You don’t know what surprises you’ll get.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    In achievement and prestige, the University of Wisconsin–Madison has long been recognized as one of America’s great universities. A public, land-grant institution, UW–Madison offers a complete spectrum of liberal arts studies, professional programs and student activities. Spanning 936 acres along the southern shore of Lake Mendota, the campus is located in the city of Madison.

     
  • richardmitnick 1:14 pm on March 21, 2020 Permalink | Reply
    Tags: (SORCE)-NASA’s Solar Radiation and Climate Experiment, , Solar research, TSIS-1 [2017] the present and TSIS-2 [2023] the future.   

    From NASA: “Solar Energy Tracker Powers Down After 17 Years” 


    From NASA

    March 20, 2020
    By Jessica Merzdorf
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    1
    The Sun is Earth’s primary power source. Energy from the Sun, called solar irradiance, drives Earth’s climate, temperature, weather, atmospheric chemistry, ocean cycles, energy balance and more. Credit: NASA / Scott Wiessinger

    After nearly two decades, the Sun has set for NASA’s SOlar Radiation and Climate Experiment (SORCE), a mission that continued and advanced the agency’s 40-year record of measuring solar irradiance and studying its influence on Earth’s climate.

    1
    SORCE. NASA

    The SORCE team turned off the spacecraft on February 25, 2020, concluding 17 years of measuring the amount, spectrum and fluctuations of solar energy entering Earth’s atmosphere — vital information for understanding climate and the planet’s energy balance. The mission’s legacy is continued by the Total and Spectral solar Irradiance Sensor (TSIS-1), launched to the International Space Station in December 2017, and TSIS-2, which will launch aboard its own spacecraft in 2023.

    3
    TSIS-1. NASA

    Monitoring Earth’s “Battery”

    The Sun is Earth’s primary power source. Energy from the Sun, called solar irradiance, drives Earth’s climate, temperature, weather, atmospheric chemistry, ocean cycles, energy balance and more. Scientists need accurate measurements of solar power to model these processes, and the technological advances in SORCE’s instruments allowed more accurate solar irradiance measurements than previous missions.

    “These measurements are important for two reasons,” said Dong Wu, project scientist for SORCE and TSIS-1 at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Climate scientists need to know how much the Sun varies, so they know how much change in the Earth’s climate is due to solar variation. Secondly, we’ve debated for years, is the Sun getting brighter or dimmer over hundreds of years? We live only a short period, but an accurate trend will become very important. If you know how the Sun is varying and can extend that knowledge into the future, you can then put the anticipated future solar input into climate models together with other information, like trace gas concentrations, to estimate what our future climate will be.”

    SORCE’s four instruments measured solar irradiance in two complementary ways: Total and spectral.

    3
    NASA’s Solar Radiation and Climate Experiment, or SORCE, collected this data on total solar irradiance, the total amount of the Sun’s radiant energy, throughout Sept. 2017. Sunspots (darkened areas on the Sun’s surface) and faculae (brightened areas) create tiny TSI variations that show up as measurable changes in Earth’s climate and systems.
    Credits: NASA / Walt Feimer

    Total solar irradiance, or TSI, is the total amount of solar energy that reaches the Earth’s outer atmosphere in a given time. Sunspots (darkened areas on the Sun’s surface) and faculae (brightened areas) create tiny TSI variations that show up as measurable changes in Earth’s climate and systems. From space, SORCE and other solar irradiance missions measure TSI without interference from Earth’s atmosphere.

    SORCE’s TSI values were slightly but significantly lower than those measured by previous missions. This was not an error — its Total Irradiance Monitor was ten times more accurate than previous instruments. This improved solar irradiance inputs into the Earth climate and weather models from what was previously available.

    “The big surprise with TSI was that the amount of irradiance it measured was 4.6 watts per square meter less than what was expected,” said Tom Woods, SORCE’s principal investigator and senior research associate at the University of Colorado’s Laboratory for Atmospheric and Space Physics (LASP) in Boulder, Colorado. “That started a whole scientific discussion and the development of a new calibration laboratory for TSI instruments. It turned out that the TIM was correct, and all the past irradiance measurements were erroneously high.”

    “It’s not often in climate studies that you make a quantum leap in measurement capability, but the tenfold improvement in accuracy by the SORCE / TIM was exactly that,” said Greg Kopp, TIM instrument scientist for SORCE and TSIS at LASP.

    SORCE’s other measurements focused on spectrally-resolved solar irradiance (SSI): The variation of solar irradiance with wavelength across the solar spectrum, covering the major wavelength regions important to Earth’s climate and atmospheric composition.

    Besides the familiar rainbow of colors in visible light, solar energy also contains shorter ultraviolet and longer infrared wavelengths, both of which play important roles in affecting Earth’s atmosphere. Earth’s atmospheric layers and surface absorb different wavelengths of energy — for example, atmospheric ozone absorbs harmful ultraviolet radiation, while atmospheric water vapor and carbon dioxide absorb longer-wavelength infrared radiation, which keeps the surface warm. SORCE was the first satellite mission to record a broad spectrum of SSI for a long period, tracking wavelengths from 1 to 2400 nanometers across its three SSI instruments.

    “For public health, ozone chemistry and ultraviolet radiation are very important, and visible light is important for climate modeling,” Wu said. “We need to know the solar variability at different wavelengths and compare these measurements with our models.”

    SORCE observed the Sun across two solar minima (periods of low sunspot activity), providing valuable information about variability over a relatively short 11-year period. But a longer record is needed to improve long-term predictions, Wu said.

    Buying Time for an Aging Mission

    SORCE was originally designed to collect data for just five years. Extending its lifespan to 17 required creative and resourceful engineering, said Eric Moyer, SORCE’s mission director at Goddard.

    “The operation and science teams at our partner organizations developed and implemented a completely new way to operate this mission when it appeared it was over because of battery capacity loss,” said Moyer. LASP and Northrup Grumman Space Systems led the development of new operational software in order to continue the SORCE mission. “The small, highly dedicated team persevered and excelled when encountering operational challenges. I am very proud of their excellent accomplishment and honored to have had the opportunity to participate in managing the SORCE mission.”

    Continuing a Bright Legacy

    As SORCE’s time in the Sun ends, NASA’s solar irradiance record continues with TSIS-1. The mission’s two instruments measure TSI and SSI with even more advanced instruments that build on SORCE’s legacy, said Wu. They have already enabled advances like establishing a new reference for the “quiet” Sun when there were no sunspots in 2019, and for comparing this to SORCE observations of the previous solar cycle minimum in 2008.

    TSIS-2 is scheduled to launch in 2023 with identical instruments to TSIS-1. Its vantage point aboard its own spacecraft will give it more flexibility than TSIS-1’s data collection aboard the ISS.

    “We are looking forward to continuing the groundbreaking science ushered in by SORCE, and to maintaining the solar irradiance data record through this decade and beyond with TSIS-1 and 2,” said LASP’s Peter Pilewskie, principal investigator for the TSIS missions. “SORCE set the standard for measurement accuracy and spectral coverage, two attributes of the mission that were key to gaining insight into the Sun’s role in the climate system. TSIS has made additional improvements that should further enhance Sun-climate studies.”

    “Solar irradiance measurements are very challenging, and the SORCE team proposed a different way, a new technology, to measure them,” said Wu. “Using advanced technology to advance our science capability, SORCE is a very good example of NASA’s spirit.”

    For more information on SORCE, visit: http://lasp.colorado.edu/home/sorce/.

    See the full article here .

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

    Please help promote STEM in your local schools.

    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 9:35 am on February 21, 2020 Permalink | Reply
    Tags: , , , , , , Giant flare from a tiny star, Solar research   

    From European Space Agency – United space in Europe: “XMM-Newton reveals giant flare from a tiny star” 

    ESA Space For Europe Banner

    From European Space Agency – United space in Europe

    United space in Europe

    20/02/2020

    For further information, please contact:

    Beate Stelzer
    Institut für Astronomie und Astrophysik Tübingen, Germany
    INAF – Osservatorio Astronomico di Palermo, Italy
    Email: stelzer@astro.uni-tuebingen.de

    Andrea De Luca
    INAF, Istituto di Astrofisica Spaziale e Fisica Cosmica
    Milano, Italy
    Email: andrea.deluca@inaf.it

    Norbert Schartel
    XMM-Newton Project Scientist
    European Space Agency
    Email: norbert.schartel@esa.int

    1
    Artist’s impression of an L dwarf star, a star with so little mass that it is only just above the boundary of actually being a star, caught in the act of emitting an enormous ‘super flare’ of X-rays, as detected by ESA’s XMM-Newton X-ray space observatory.

    A star of about eight percent the Sun’s mass has been caught emitting an enormous ‘super flare’ of X-rays – a dramatic high-energy eruption that poses a fundamental problem for astronomers, who did not think it possible on stars that small.

    The culprit, known by its catalogue number J0331-27, is a kind of star called an L dwarf. This is a star with so little mass that it is only just above the boundary of actually being a star. If it had any less mass, it would not possess the internal conditions necessary to generate its own energy.

    Astronomers spotted the enormous X-ray flare in data recorded on 5 July 2008 by the European Photon Imaging Camera (EPIC) onboard ESA’s XMM-Newton X-ray observatory. In a matter of minutes, the tiny star released more than ten times more energy of even the most intense flares suffered by the Sun.

    2
    A giant flare suffered by our own Sun, captured on 27 July 1999 by the ESA/NASA Solar and Heliospheric Observatory (SOHO)

    ESA/NASA SOHO

    Flares are released when the magnetic field in a star’s atmosphere becomes unstable and collapses into a simpler configuration. In the process, it releases a large proportion of the energy that has been stored in it.

    This explosive release of energy creates a sudden brightening – the flare – and this is where the new observations present their biggest puzzle.

    “This is the most interesting scientific part of the discovery, because we did not expect L-dwarf stars to store enough energy in their magnetic fields to give rise to such outbursts,” says Beate Stelzer, Institut für Astronomie und Astrophysik Tübingen, Germany, and INAF – Osservatorio Astronomico di Palermo, Italy, who was part of the study team.

    Energy can only be placed in a star’s magnetic field by charged particles, which are also known as ionised material and created in high-temperature environments. As an L dwarf, however, J0331-27 has a low surface temperature for a star – just 2100K compared to the roughly 6000K on the Sun. Astronomers did not think such a low temperature would be capable of generating enough charged particles to feed so much energy into the magnetic field. So the conundrum is: how a super flare is even possible on such a star.

    “That’s a good question,” says Beate. “We just don’t know – nobody knows.”

    The super flare was discovered in the XMM-Newton data archive as part of a large research project led by Andrea De Luca of INAF – Istituto di Astrofisica Spaziale e Fisica Cosmica in Milan, Italy. The project studied the temporal variability of around 400 000 sources detected by XMM-Newton over 13 years

    Andrea and collaborators were particularly looking for peculiar phenomena and in J0331-27 they certainly got that. A number of similar stars had been seen to emit super flares in the optical part of the spectrum, but this is the first unambiguous detection of such an eruption at X-ray wavelengths.

    The wavelength is significant because it signals which part of the atmosphere the super flare is coming from: optical light comes from deeper in the star’s atmosphere, near its visible surface, whereas X-rays come from higher up in the atmosphere.

    Understanding the similarities and differences between this new – and so far unique – super flare on the L dwarf and previously observed flares, detected at all wavelengths on stars of higher mass is now a priority for the team. But to do that, they need to find more examples.

    “There is still much to be discovered in the XMM-Newton archive,” says Andrea. “In a sense, I think this is only the tip of the iceberg.”

    One clue they do have is that there is only one flare from J0331-27 in the data, despite XMM-Newton having observed the star for a total of 3.5 million seconds – about 40 days. This is peculiar because other flaring stars tend to suffer from numerous smaller flares too.

    “The data seem to imply that it takes an L dwarf longer to build up the energy, and then there is one sudden big release,” says Beate.

    Stars that flare more frequently release less energy each time, while this L dwarf seems to release energy very rarely but then in a really big event. Why this might be the case is still an open question that needs further investigation.

    “The discovery of this L dwarf super flare is a great example of research based on the XMM-Newton archive, demonstrating the mission’s enormous scientific potential,” says Norbert Schartel, XMM-Newton project scientist for ESA. “I look forward to the next surprise.”

    Science paper:
    “EXTraS discovery of an X-ray superflare from an L dwarf”
    Astronomy & Astrophysics.

    The discovery was made as a result of the Exploring the X-ray Transient and variable Sky (EXTraS) project, a EU/FP7 project devoted to a systematic variability study of the X-ray sources in the XMM-Newton public archive.

    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 European Space Agency (ESA), 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.

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  • richardmitnick 3:50 pm on February 20, 2020 Permalink | Reply
    Tags: , Solar research, SunPy   

    From AAS NOVA: ” Exploring Our Star with SunPy” 

    AASNOVA

    From AAS NOVA

    19 February 2020
    Susanna Kohler

    1
    SunPy is a community-developed, Python-based software library that provides tools for analyzing observations of the Sun and the heliosphere. [SunPy logo: Steven Christe; background image: SDO/AIA]

    Python, one of the foremost high-level programming languages, has played a growing role in the analysis of astronomical data. With the recent release of a new software package, SunPy, it’s now easier than ever for solar physicists to use Python as well.

    1
    An example of a SunPy-generated Map visualization using data from the Solar Dynamics Observatory’s AIA instrument. The bottom panel shows a zoomed-in view from the top panel, focusing on an erupting flare. [Adapted from The SunPy Community et al. 2020]

    Juggling Ones and Zeros

    The modern era of astronomy relies heavily on computer software to advance our understanding of the universe. Long gone are the days of sketching what we see through telescope eyepieces; now astronomers receive their telescope observations in the form of files full of data that must be carefully analyzed using complex code bases.

    Preferences for one programming language over another evolve over time as our needs evolve — and Python is currently a rising star. Major companies like Google, Wikipedia, and Facebook all make use of Python, and astronomers are increasingly adopting Python for their data analysis in place of past staples like Fortran and IDL.

    A Shared Enterprise

    The field of solar physics is driven by publicly available observations of the Sun that stream in on a constant basis from a number of ground- and space-based observatories. As solar physics, like the rest of astronomy, is a largely collaborative field, it makes sense to share the software tools that are used to analyze this common data.

    To this end, a group of solar physicists has come together to produce SunPy, a community-developed free and open-source software package that consists of tools for analyzing solar and heliospheric data. In a recent article, the SunPy team has detailed this Python-based package and the overarching SunPy project, which develops and maintains the package and supports the ecosystem surrounding it.

    3
    Growth of the SunPy codebase over time — both the total lines of code (solid line) and comments (dashed line). The dip after version 0.9 is the result of a major code reorganization. [The SunPy Community et al. 2020]

    What Can SunPy Do For You?

    Looking to explore some solar data? The SunPy software package is freely accessible, and its first official stable release was issued last year. As of version 1.0, SunPy consisted of nearly 50,000 lines of code that support a large set of common tasks in the analysis of solar data.

    Here are just a few things you can do using the SunPy package:

    Query and download data from many different solar missions and instruments via a general, standard, and consistent interface.
    Load and visualize time series data — measurements of how, say, a particular type of flux from a region changes over time — and images.
    Perform transformations between the variety of coordinate systems commonly used to describe events and features both on the Sun and within the heliosphere.

    4
    SunPy comes with a detailed user’s guide and example gallery to assist users. [SunPy]

    Looking Ahead

    SunPy will be supported with two new releases planned per year. Future development already on the books includes support for generic spectra, multidimensional data sets, and a standardized approach to metadata.

    The SunPy team hopes to grow community involvement and establish financial support in the future, in order to further expand SunPy development. In the meantime, the SunPy project’s team of volunteer developers have done an admirable job of building a powerful set of shared tools for the solar physics community.

    Citation

    “The SunPy Project: Open Source Development and Status of the Version 1.0 Core Package,” The SunPy Community et al 2020 ApJ 890 68.

    https://iopscience.iop.org/article/10.3847/1538-4357/ab4f7a

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    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

     
  • richardmitnick 10:15 am on February 18, 2020 Permalink | Reply
    Tags: , , Solar research   

    From European Space Agency – United space in Europe: “First Solar Orbiter instrument sends measurements” 

    ESA Space For Europe Banner

    From European Space Agency – United space in Europe

    United space in Europe

    2.18.20

    Daniel Müller
    ESA Solar Orbiter Project Scientist
    Email: daniel.mueller@esa.int

    Yannis Zouganelis
    ESA Solar Orbiter Deputy Project Scientist
    Email: yannis.zouganelis@esa.int

    ESA Media Relations
    Email: media@esa.int

    1

    First measurements by a Solar Orbiter science instrument reached the ground on Thursday 13 February providing a confirmation to the international science teams that the magnetometer on board is in good health following a successful deployment of the spacecraft’s instrument boom.

    Solar Orbiter, ESA’s new Sun-exploring spacecraft, launched on Monday 10 February.

    ESA/NASA Solar Orbiter depiction

    It carries ten scientific instruments, four of which measure properties of the environment around the spacecraft, especially electromagnetic characteristics of the solar wind, the stream of charged particles flowing from the Sun. Three of these ‘in situ’ instruments have sensors located on the 4.4 m-long boom.

    “We measure magnetic fields thousands of times smaller than those we are familiar with on Earth,” says Tim Horbury of Imperial College London, Principal Investigator for the Magnetometer instrument (MAG). “Even currents in electrical wires make magnetic fields far larger than what we need to measure. That’s why our sensors are on a boom, to keep them away from all the electrical activity inside the spacecraft.”

    Observing magnetic field as boom deploys.

    2
    Solar Orbiter boom deployment and first magnetic field measurements.

    Ground controllers at the European Space Operations Centre in Darmstadt, Germany, switched on the magnetometer’s two sensors (one near the end of the boom and the other close to the spacecraft) about 21 hours after liftoff. The instrument recorded data before, during and after the boom’s deployment, allowing the scientists to understand the influence of the spacecraft on measurements in the space environment.

    “The data we received shows how the magnetic field decreases from the vicinity of the spacecraft to where the instruments are actually deployed,” adds Tim. “This is an independent confirmation that the boom actually deployed and that the instruments will, indeed, provide accurate scientific measurements in the future.”

    As the titanium/carbon-fibre boom stretched out over an overall 30-minute period on Wednesday, almost three days after liftoff, the scientists could observe the level of the magnetic field decrease by about one order of magnitude. While at the beginning they saw mostly the magnetic field of the spacecraft, at the end of the procedure, they got the first glimpse of the significantly weaker magnetic field in the surrounding environment.

    3
    Solar Orbiter carries ten instruments, some of which consist of multiple instrument packages. Three of the spacecraft’s four ‘in situ’ instruments, which measure the environment in the vicinity of the spacecraft, are located on Solar Orbiter’s 4.4 m boom.

    “Measuring before, during, and after the boom deployment helps us to identify and characterise signals that are not linked to the solar wind, such as perturbations coming from the spacecraft platform and other instruments,” says Matthieu Kretzschmar, of Laboratoire de Physique et Chimie de l’Environnement et de l’Espace in Orleans, France, Lead Co-investigator behind another sensor located on the boom, the high frequency magnetometer of the Radio and Plasma Waves instrument (RPW) instrument.

    “The spacecraft underwent extensive testing on ground to measure its magnetic properties in a special simulation facility, but we couldn’t fully test this aspect until now, in space, because the test equipment usually prevents us from reaching the needed very low level of magnetic field fluctuations,” he adds.

    Next, the instruments will have to be calibrated before true science can begin.

    Warming up for science


    Solar Orbiter launch to the Sun. Solar Orbiter’s journey to the Sun as it prepares to commence its ground-breaking mission.

    “Until the end of April, we will be gradually turning on the in-situ instruments and checking whether they are working correctly,” says Yannis Zouganelis, ESA’s deputy project scientist for the Solar Orbiter mission. “By the end of April, we will have a better idea of the performance of the instruments and hopefully start collecting first scientific data in mid-May.”

    In addition to the instrument boom, the deployments of three antennas of the RPW instrument, which will study characteristics of electromagnetic and electrostatic waves in the solar wind, were successfully completed in the early hours of Thursday 13 February. The data of these specific deployments still need to be analysed.

    In addition to the four in situ instruments, Solar Orbiter carries six remote-sensing instruments, essentially telescopes, that will be imaging the surface of the Sun at various wavelengths, obtaining the closest ever views of our parent star.

    “The remote-sensing instruments will be commissioned in the coming months, and we look forward to testing them further in June, when Solar Orbiter gets nearer to the Sun,” Yannis adds.

    Unravelling the Sun’s mysteries

    The combination of both sets of instruments will allow scientists to link what happens on the Sun to the phenomena measured in the solar wind, enabling them to tackle mysteries such as the 11-year cycle of solar activity, the generation of the Sun’s magnetic field and how solar wind particles are accelerated to high energies.

    “The ten instruments onboard our mission will be playing together like instruments in an orchestra,” says ESA Solar Orbiter project scientist Daniel Müller. “We have just started the rehearsal, and one by one, additional instruments will join. Once we are complete, in a few months’ time, we will be listening to the symphony of the Sun.”

    Notes for editors

    Solar Orbiter is an ESA-led mission with strong NASA participation. The prime contractor is Airbus Defence and Space in Stevenage, UK. Solar Orbiter is the first ‘medium’-class mission implemented in the Cosmic Vision 2015-25 programme, the current planning cycle for ESA’s space science missions.

    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 European Space Agency (ESA), 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.

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  • richardmitnick 3:14 pm on February 16, 2020 Permalink | Reply
    Tags: "Solar wind samples suggest new physics of massive solar ejections", , , , , Solar research,   

    From U Hawaii at Manoa: “Solar wind samples suggest new physics of massive solar ejections” 

    From U Hawaii at Manoa

    February 12, 2020
    Marcie Grabowski

    1
    An image of active regions on the Sun from NASA’s Solar Dynamics Observatory. The glowing hot gas traces out the twists and loops of the Sun’s magnetic field lines. Image credit: NASA/SDO/AIA

    NASA SDO

    A new study [Meteoritics and Planetary Science] led by the University of Hawai‘i (UH) at Mānoa has helped refine understanding of the amount of hydrogen, helium and other elements present in violent outbursts from the Sun, and other types of solar “wind,” a stream of ionized atoms ejected from the Sun.

    Coronal mass ejections (CME) are giant plasma bursts that erupt from the sun, heading out into the solar system at speeds as fast as 2 million miles per hour. Like the sun itself, the majority of a CME’s atoms are hydrogen. When these particles interact with Earth’s atmosphere, they lead to the brilliant multicolored lights of the Aurora Borealis. They also have the potential to knock out communications, bringing modern civilization to a standstill.

    And their cause is pretty much a mystery.

    UH Manoa School of Ocean and Earth Science and Technology (SOEST) researcher Gary Huss led a team of scientists in investigating a sample of solar wind collected by NASA’s Genesis mission.

    Most of our understanding of the composition of the sun, which makes up 99.8% of the mass of the Solar System, has come from astronomical observations and measurements of a rare type of meteorite. In 2001, the Genesis probe headed to space to gather samples of solar wind in pure materials, and bring the material back to Earth to be studied in a lab. Those samples represented particles gathered from different sources of solar wind, including those thrown off by CMEs.

    The Genesis samples allowed for a more accurate assessment of the hydrogen abundance in CMEs and other components of the solar wind. About 91% of the Sun’s atoms are hydrogen, so everything that happens in the solar wind plasma is influenced by hydrogen.

    However, measuring hydrogen in the Genesis samples proved to be a challenge. An important component of the recent work was to develop appropriate standards using terrestrial minerals with known amounts of hydrogen, implanted with hydrogen by a laboratory accelerator.

    A precise determination of the amount of hydrogen in the solar wind allowed researchers to discern small differences in the amount of neon and helium relative to hydrogen ejected by these massive solar ejections. Helium and neon, both noble gases, are difficult to ionize. The new measurements of hydrogen showed that helium and neon were both enriched in coronal mass ejections, providing clues to the underlying physics in the Sun that causes the coronal mass ejections.

    In the very energetic event, “the ejected material appears to be enriched almost systematically in atoms that require the most energy to ionize,” said Ryan Ogliore, co-author and assistant professor of physics at Washington University in St. Louis. “That tells us a lot about the physics involved in the first stages of the explosion on the Sun.”

    This finding brings researchers one step closer to understanding the origins of these particular solar events.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    U Hawaii 2.2 meter telescope, Mauna Kea, Hawaii, USA

    U Hawaii 2.2 meter telescope, Mauna Kea, Hawaii, USA,4,207 m (13,802 ft) above sea level

    The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth.

    Keck Observatory, operated by Caltech and the University of California, Maunakea Hawaii USA, 4,207 m (13,802 ft)

    The two, 10-meter optical/infrared telescopes near the summit of Maunakea on the island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrographs and world-leading laser guide star adaptive optics systems.

    Pann-STARS 1 Telescope, U Hawaii, situated at Haleakala Observatories near the summit of Haleakala , on the island of Maui in Hawaii, USA, Pann-STARS 1 Telescope, U Hawaii, situated at Haleakala Observatories near the summit of Haleakala in Hawaii, USA, altitude 3,052 m (10,013 ft)altitude 3,052 m (10,013 ft)


    System Overview

    The University of Hawai‘i includes 10 campuses and dozens of educational, training and research centers across the Hawaiian Islands. As the public system of higher education in Hawai‘i, UH offers opportunities as unique and diverse as our Island home.

    The 10 UH campuses and educational centers on six Hawaiian Islands provide unique opportunities for both learning and recreation.

    UH is the State’s leading engine for economic growth and diversification, stimulating the local economy with jobs, research and skilled workers.

     
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