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  • richardmitnick 7:43 am on July 29, 2014 Permalink | Reply
    Tags: , , , , ESA Herschel   

    From ESA: “Nearby M33 galaxy blossoming with star birth” 

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    European Space Agency

    28/07/2014
    No Writer Credit

    The spiral galaxy M33, also known as the Triangulum Galaxy, is one of our closest cosmic neighbours, just three million light-years away. Home to some forty billion stars, it is the third largest in the Local Group of galaxies after the Andromeda Galaxy (M31) and our own Milky Way.

    m33

    M33 is popular with astrophotographers and from exceptionally dark sites it can even be seen with the naked eye. Thanks to its orientation, we can enjoy a face-on view of the beautiful spiral structure of the galaxy’s disc.

    This image, from ESA’s Herschel space observatory, shows M33 in far-infrared light, revealing the glow of cosmic dust in the interstellar medium that permeates the galaxy. The patchy, disorganised structure of M33’s spiral arms resembles a tuft of wool, leading astronomers to classify it as a flocculent spiral galaxy.

    The brightest spots sprinkled along the spiral arms are dense pockets of gas and dust where massive stars are born. The most prominent of these is NGC604, visible in the upper left spiral arm. This is an enormous star-forming region where hundreds of thousands of stars are taking shape.

    The image is a composite of the wavelengths: 70 microns (blue), 100 microns (green) and 160 microns (red). At the shortest wavelengths, astronomers trace warmer dust, revealing individual regions of star formation and parent clouds. At longer wavelengths, they detect emission from colder dust, outlining some of the cool dust reservoir along the galaxy’s winding spiral arms. This is where stars may be born in the future.

    The image spans about one degree on each side; north is up and east is to the left. The data were collected with Herschel’s PACS instrument as part of the Herschel M33 extended survey (HerM33es) Key Programme to study the star formation in the Triangulum Galaxy.

    ESA Herschel PACS
    ESA/Herschek PACS Instrument

    See the full article here.

    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 5:09 pm on July 25, 2014 Permalink | Reply
    Tags: , , , , ESA Herschel   

    From ESA/Herschel: “Herschel Uncovers a Dearth of Oxygen near a New Star” 

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    European Space Agency

    June 9, 2014
    No Writer credit

    A cosmic mystery regarding oxygen has deepened, thanks to new findings from the Herschel Space Observatory, a European Space Agency mission with important NASA contributions. Observations of a newly forming star have revealed strangely low levels of molecular oxygen, the kind we breathe, in the emerging star’s gassy, dusty environment.

    ESA Herschel
    ESA/Herschel

    Oxygen is the third most abundant element in the universe after hydrogen and helium. Yet searches in outer space for the simplest molecular version of oxygen, O2, have come up mostly empty-handed. Herschel’s discovery raises questions about our understanding of the complex chemistry involved in the birth of stars and planets.

    “With these new results from Herschel, we’re confirming just how little molecular oxygen there is in interstellar space,” said Umut Yildiz, lead author of the new paper and a molecular astrophysicist working as a Caltech postdoctoral scholar at NASA’s Jet Propulsion Laboratory and formerly at the Leiden Observatory in the Netherlands. “Along with understanding why oxygen molecules are generally so rare, we need to figure out what is special about the regions where we do find the molecules, albeit in small amounts, and what that tells us about the chemistry there and in the broader universe.”

    To make the discovery, Herschel had to take a good, long look at a protostar about 750 light years away. Ample observing time was needed to pick up the signatures of any molecular oxygen present in the gas- and dust-strewn neighborhood surrounding the fledging star.

    Herschel detected only small traces of the two-atom oxygen molecule in the gas clouds where stars form. Specifically, astronomers found only one oxygen molecule for every six billion hydrogen molecules in the protostar’s vicinity. This flies in the face of theoretical chemical models that predict 6,000 times more oxygen should have been present.

    The research team thinks that most of the available oxygen must end up freezing onto dust grains around the star. The grains, along with various gases and ices, encircle the star in a so-called protoplanetary disk, from which planets, asteroids and other solar system objects will coalesce, piece by piece. The oxygen then combines with hydrogen to form water molecules rather than linking up to create molecular oxygen.

    “We want to explain why so little O2 is observed in the dense envelope of the protostar,” said Yildiz. “A possible explanation is that oxygen freezes out and converts into water in the early stages of star formation, so the gas and ice present in later stages, during planetary disk formation, are very poor in O2.”

    Findings of this sort were not possible before Herschel, and will not be again until another space telescope takes to the skies that can see in sub-millimeter light. Ground-based observatories cannot identify interstellar oxygen molecules due to the molecular oxygen in Earth’s atmosphere.

    The Herschel findings tie in to the origin of that Earthly, atmospheric oxygen, which is a story still being pieced together. Molecular oxygen is highly reactive, eagerly breaking apart to bind with other molecules. Accordingly, the free oxygen we breathe today could not have come from space in molecular form. Instead, our oxygen started out bound up in water, carbon dioxide and other common, simple, oxygen-containing compounds. That bound oxygen must have later been set free by life or other chemical processes.

    Scientists think that the first photosynthetic microbes that emerged on Earth over 3.5 billion years ago made use of plentiful carbon dioxide, emitting oxygen as a waste product. Over hundreds of millions of years, Earth’s atmosphere came to hold considerable oxygen stores, although there’s some debate over the timing of these events. Gauging available oxygen amounts and types is therefore not only key for revealing the chemistry of the rise of stars and planets, but also life.

    “The oxygen molecule is one of the most essential molecules for life,” said Yildiz. “It is important to search deeply near star-forming regions to understand the origin of molecular oxygen in protoplanetary disks and eventually exoplanetary atmospheres.”

    See the full article here.

    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 12:02 pm on July 1, 2014 Permalink | Reply
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    From ESA: “Young Sun’s Violent History Solves Meteorite Mystery” 

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    European Space Agency

    1 July 2014

    Markus Bauer
    ESA Science and Robotic Exploration Communication Officer
    Tel: +31 71 565 6799
    Mob: +31 61 594 3 954
    Email: markus.bauer@esa.int

    Cecilia Ceccarelli
    Institute de Planétologie et d’Astrophysique de Grenoble
    Grenoble, France
    Tel: +33 476 514 201
    Email: Cecilia.Ceccarelli@obs.ujf-grenoble.fr

    Carsten Dominik
    Astronomical Institute “Anton Pannekoek”, University of Amsterdam
    Amsterdam, The Netherlands
    Tel: +31 6 43 710 210
    Email: dominik@uva.nl

    Göran Pilbratt
    Herschel Project Scientist
    Tel: +31 71 565 3621
    Email: gpilbratt@cosmos.esa.int

    Astronomers using ESA’s Herschel space observatory to probe the turbulent beginnings of a Sun-like star have found evidence of mighty stellar winds that could solve a puzzling meteorite mystery in our own back yard.

    sun

    ESA Herschel
    ESA/Herschel

    In spite of their tranquil appearance in the night sky, stars are scorching furnaces that spring to life through tumultuous processes – and our 4.5 billion-year-old Sun is no exception. To glimpse its harsh early days, astronomers gather clues not only in the Solar System but also by studying young stars elsewhere in our Galaxy.

    Using Herschel to survey the chemical composition of regions where stars are being born today, a team of astronomers has noticed that one object in particular is different.

    The unusual source is a prolific stellar nursery called OMC2 FIR4, a clump of new stars embedded in a gaseous and dusty cloud near to the famous Orion Nebula.

    orion
    In one of the most detailed astronomical images ever produced, NASA/ESA’s Hubble Space Telescope captured an unprecedented look at the Orion Nebula. … This extensive study took 105 Hubble orbits to complete. All imaging instruments aboard the telescope were used simultaneously to study Orion. The Advanced Camera mosaic covers approximately the apparent angular size of the full moon.

    gust
    Violent wind gusting around protostar in Orion

    “To our great surprise, we found that the proportion of two chemical species, one based on carbon and oxygen and the other on nitrogen, is much smaller in this object than in any other protostar we know,” says Dr Cecilia Ceccarelli, of the Institute de Planétologie et d’Astrophysique de Grenoble, France, who lead the study with Dr Carsten Dominik of the University of Amsterdam in the Netherlands.

    In an extremely cold environment, the measured proportion could arise by one of the two compounds freezing onto dust grains and becoming undetectable. However, at the relatively ‘high’ temperature of about –200°C found in star-forming regions like OMC2 FIR4, this should not occur.

    “The most likely cause in this environment is a violent wind of very energetic particles, released by at least one of the embryonic stars taking shape in this proto-stellar cocoon,” Dr Ceccarelli adds.

    The most abundant molecule in star-forming clouds, hydrogen, can be broken apart by cosmic rays, energetic particles that permeate the entire Galaxy. The hydrogen ions then combine with other elements that are present – albeit only in trace amounts – in these clouds: carbon and oxygen, or nitrogen.

    Normally, the nitrogen compound is also quickly destroyed, yielding more hydrogen for the carbon and oxygen compound. As a result, the latter is far more abundant in all known stellar nurseries.

    Strangely enough, though, this was not the case for OMC2 FIR4, suggesting that an additional wind of energetic particles is destroying both chemical species, keeping their abundances more similar.

    Astronomers think that a similarly violent wind of particles also gusted through the early Solar System, and this discovery might finally point to an explanation for the origin of a particular chemical element seen in meteorites.

    Meteorites are the remains of interplanetary debris that survived the trip through our planet’s atmosphere. These cosmic messengers are one of the few tools we have to directly probe the elements in our Solar System.

    “Some elements detected in meteorites reveal that, long ago, these rocks contained a form of beryllium: this is quite puzzling, as we can’t quite understand how it got there,” explains Dr Dominik.

    The formation of this isotope – beryllium-10 – in the Universe is an intricate puzzle of its own. Astronomers know that it is not produced in the interior of stars, like some other elements, nor in the supernova explosion that happens at the end of a massive star’s life.

    The majority of beryllium-10 was formed in collisions of very energetic particles with heavier elements like oxygen. But since this isotope decays very quickly into other elements, it must have been produced just before it was incorporated in the rocks that would later appear on Earth as meteorites.

    In order to trigger these reactions and produce an amount of beryllium matching that recorded in meteorites, our own Sun must have blown a violent wind in its youth.

    These new observations of OMC2 FIR4 give a very strong hint that it is possible for a young star to do this.

    “Observing star-forming regions with Herschel not only provides us with a view on what happens beyond our cosmic neighbourhood, but it’s also a crucial way to piece together the past of our own Sun and Solar System,” says Göran Pilbratt, ESA’s Herschel project scientist.

    More information

    Herschel finds evidence for stellar wind particles in a protostellar envelope: is this what happened to the young Sun? by C. Ceccarelli et al. is published in The Astrophysical Journal Letters, July 2014.

    The study is based on observations performed with the Heterodyne Instrument for the Far-Infrared (HIFI) [NASA/JPL addition] on Herschel, as part of the Herschel Guaranteed Time Key Programme Chemical HErschel Surveys of Star forming regions (CHESS).

    ESA Herschel HIFI
    ESO Herschel HIFI

    See the full article here.

    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 5:50 pm on June 23, 2014 Permalink | Reply
    Tags: , , , , ESA Herschel   

    From ESA: “From oldest to youngest: a line of star nurseries” 

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    European Space Agency

    23/06/2014
    No Writer Credit

    Just as children are sorted into age groups at school, so the seeds of new stars can also be found in ‘classes’ of others of similar ages. This is especially true when the birth of stars in a cloud of gas and dust is triggered by an external event, like the explosion of a nearby supernova.
    This image from ESA’s Herschel space observatory shows a sequence of star-forming regions in the molecular cloud W48, some 10 000 light-years away in the constellation Aquila (the Eagle).

    stars

    ESA Herschel
    ESA/Herschel

    The blue, jellyfish-shaped cloud at the lower left is the oldest stellar nursery in the image. Young and massive stars embedded within it have shaped it into a bubble and heated the diffuse gas, making it shine at the longest wavelengths probed by Herschel.

    To its right, another glowing cloud conceals clumps that will evolve into massive stars. These clumps, some of which are visible as bright blotches of light, are also lined up by their age: the older ones at the lower-left and the younger ones to the upper-right. The youngest in this sequence is the small cyan lump at the centre of the image, harbouring the seeds of future massive stars.

    Astronomers believe that this sequence of stellar birth is the result of dozens of supernovas that exploded over 10 million years ago in a region called Aquila Supershell, beyond the left edge of this image. Compressing the surrounding material, these supernovas may have initiated a wave of star formation that sparked, one by one, these stellar cribs.

    The image is a composite of the wavelengths of 70 microns (blue), 160 microns (green) and 250 microns (red) and spans about one degree on the long side. North is to the upper-left and east is to the lower left. The data were acquired with Herschel’s PACS and SPIRE instruments in September 2010, as part of a larger map of the W48 molecular complex in the HOBYS Key Programme. This was first published in a paper by Q. Nguyen Luong, et al. 2011. A more detailed study of the star-forming regions shown in this image is presented in a paper by K.L.J. Rygl, et al. 2014.

    ESA Herschel PACS
    PACS

    ESA Herschel SPIRE
    SPIRE

    See the full article here.

    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 10:59 am on June 17, 2014 Permalink | Reply
    Tags: , , , , ESA Herschel   

    From ESA: “New molecules around old stars” 

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    European Space Agency

    17 June 2014
    Markus Bauer
    ESA Science and Robotic Exploration Communication Officer
    Tel: +31 71 565 6799
    Mob: +31 61 594 3954
    Email: markus.bauer@esa.int

    Isabel Aleman
    Leiden Observatory, University of Leiden, the Netherlands
    Email: aleman@strw.leidenuniv.nl

    Mireya Etxaluze
    Group of Molecular Astrophysics, Instituto de Ciencias de los Materiales de Madrid, CSIC, Spain
    Email: m.etxaluze@icmm.csic.es

    Göran Pilbratt
    ESA Herschel Project Scientist
    Tel: +31 71 565 3621
    Email: gpilbratt@rssd.esa.int

    Using ESA’s Herschel space observatory, astronomers have discovered that a molecule vital for creating water exists in the burning embers of dying Sun-like stars.

    ESA Herschel
    ESA/Herschel

    When low- to middleweight stars like our Sun approach the end of their lives, they eventually become dense, white dwarf stars. In doing so, they cast off their outer layers of dust and gas into space, creating a kaleidoscope of intricate patterns known as planetary nebulas.

    These actually have nothing to do with planets, but were named in the late 18th century by astronomer William Herschel, because they appeared as fuzzy circular objects through his telescope, somewhat like the planets in our Solar System.

    helix
    Water-building molecule in Helix Nebula

    Over two centuries later, planetary nebulas studied with William Herschel’s namesake, the Herschel space observatory, have yielded a surprising discovery.

    Like the dramatic supernova explosions of weightier stars, the death cries of the stars responsible for planetary nebulas also enrich the local interstellar environment with elements from which the next generations of stars are born.

    While supernovas are capable of forging the heaviest elements, planetary nebulas contain a large proportion of the lighter ‘elements of life’ such as carbon, nitrogen, and oxygen, made by nuclear fusion in the parent star.

    wb
    Water-building molecule in Ring Nebula

    A star like the Sun steadily burns hydrogen in its core for billions of years. But once the fuel begins to run out, the central star swells into a red giant, becoming unstable and shedding its outer layers to form a planetary nebula.

    The remaining core of the star eventually becomes a hot white dwarf pouring out ultraviolet radiation into its surroundings.

    This intense radiation may destroy molecules that had previously been ejected by the star and that are bound up in the clumps or rings of material seen in the periphery of planetary nebulas.

    The harsh radiation was also assumed to restrict the formation of new molecules in those regions.

    But in two separate studies using Herschel astronomers have discovered that a molecule vital to the formation of water seems to rather like this harsh environment, and perhaps even depends upon it to form. The molecule, known as OH+, is a positively charged combination of single oxygen and hydrogen atoms.

    In one study, led by Dr Isabel Aleman of the University of Leiden, the Netherlands, 11 planetary nebulas were analysed and the molecule was found in just three.

    What links the three is that they host the hottest stars, with temperatures exceeding 100 000ºC.

    “We think that a critical clue is in the presence of the dense clumps of gas and dust, which are illuminated by UV and X-ray radiation emitted by the hot central star,” says Dr Aleman.

    “This high-energy radiation interacts with the clumps to trigger chemical reactions that leads to the formation of the molecules.”

    ho
    Herschel observations of Helix Nebula

    Meanwhile, another study, led by Dr Mireya Etxaluze of the Instituto de Ciencia de los Materiales de Madrid, Spain, focused on the Helix Nebula, one of the nearest planetary nebulas to our Solar System, at a distance of 700 light years.

    The central star is about half the mass of our Sun, but has a far higher temperature of about 120 000ºC. The expelled shells of the star, which in optical images appear reminiscent of a human eye, are known to contain a rich variety of molecules.

    Herschel mapped the presence of the crucial molecule across the Helix Nebula, and found it to be most abundant in locations where carbon monoxide molecules, previously ejected by the star, are most likely to be destroyed by the strong UV radiation.

    Once oxygen atoms have been liberated from the carbon monoxide, they are available to make the oxygen–hydrogen molecules, further bolstering the hypothesis that the UV radiation may be promoting their creation.

    The two studies are the first to identify in planetary nebulas this critical molecule needed for the formation of water, although it remains to be seen if the conditions would actually allow water formation to proceed.

    “The proximity of the Helix Nebula means we have a natural laboratory on our cosmic doorstep to study in more detail the chemistry of these objects and their role in recycling molecules through the interstellar medium,” says Dr Etxaluze.

    “Herschel has traced water across the Universe, from star-forming clouds to the asteroid belt in our own Solar System,” says Göran Pilbratt, ESA’s Herschel project scientist.

    “Now we have even found that stars like our Sun could contribute to the formation of water in the Universe, even as they are in their death throes.”

    Herschel planetary nebula survey (HerPlaNS). First detection of OH+ in planetary nebulae, by I. Aleman et al., and Herschel spectral-mapping of the Helix Nebula (NGC 7293): extended CO photodissociation and OH+ emission, by M. Etxaluze et al., are published in Astronomy & Astrophysics.

    HerPlaNS (The Herschel Planetary Nebulae Survey) is a survey of 11 planetary nebulas aiming the study the formation and evolution of the circumstellar material by tracing the dust and gas components. The HerPlaNS team is led by Toshiya Ueta from the University of Denver.

    The MESS (Mass loss of Evolved StarS) consortium studies a wide variety of evolved stars (including planetary nebulas) to better understand the mass loss in these objects, the dust and gas chemistry in the ejected material, and the processes shaping the nebulae. The MESS consortium is led by Martin Groenewegen (Royal Observatory of Belgium) and the study of planetary nebulas within the group is led by Peter van Hoof (Royal Observatory of Belgium).

    See the full article here.

    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 3:03 pm on April 29, 2014 Permalink | Reply
    Tags: , , , , ESA Herschel   

    From Herschel at ESA: “Herschel discovers mature galaxies in the young Universe” 

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    European Space Agency

    ESA Herschel
    Herschel

    29 April 2014

    James Rhoads
    School of Earth and Space Exploration
    Arizona State University
    Tempe, AZ 85287, USA
    Email: James.Rhoadsasu.edu
    Phone: +1-480-727-7133

    Sangeeta Malhotra
    School of Earth and Space Exploration
    Arizona State University
    Tempe, AZ 85287, USA
    Email: Sangeeta.Malhotraasu.edu
    Phone: +1-480-965-2552

    Göran Pilbratt
    Herschel Project Scientist
    Scientific Support Office
    Science and Robotic Exploration Directorate
    ESA, The Netherlands
    Email: gpilbrattrssd.esa.int
    Phone: +31-71-565-3621

    When galaxies form, they accumulate mass by gravitationally attracting vast, external gas clouds. As the gas clouds enter the galaxy, they fall into haphazard orbits. These disordered paths cause turbulence in the host galaxies, which can drive star formation.

    To investigate the internal conditions of forming galaxies James Rhoads and Sangeeta Malhotra, both from Arizona State University, and colleagues targeted two young galaxies, known as S0901 and the Clone. The light from both galaxies has taken 10 billion years to reach us across space. Thus, we are seeing them when they were comparatively young.

    “The purpose of this project is to study the physical conditions of gas in those galaxies. We wanted to know: are they similar to the galaxies around us or is there some difference in their physical conditions,” says Rhoads.

    The two galaxies they choose to study are average galaxies for that time in cosmic history. This means that they are about 10-20 per cent the size of our Milky Way, which is considered an average galaxy in the present-day Universe.

    Studying galaxies so far away is usually hampered because they appear too dim to study effectively but in this case, the researchers were helped by a cosmic magnifier known as a gravitational lens. The two galaxies both sit behind intervening groups of galaxies, whose gravity warps space. As described by Albert Einstein’s General Theory of Relativity, this warping acts like a lens. Although it distorts the images of the young galaxies, it helps by magnifying their light, thus bringing them within reach of Herschel’s HIFI instrument.

    ESA Herschel HIFI
    HIFI

    image
    Lensed image of galaxy S0901. Credit: NASA/STScI; S. Allam and team; and the Master Lens Database (masterlens.org), L. A. Moustakas, K. Stewart, et al. (2014)

    spec
    Herschel spectrum of the galaxy S0901. Credit: ESA/Herschel/HIFI. Acknowledgments: James Rhoads and Sangeeta Malhotra, Arizona State University, USA

    The researchers used HIFI to investigate the infrared light of ionized carbon, which is emitted at a wavelength of 158 micrometres (a frequency of 1900 GHz). This spectral line is produced in the clouds that surround star-forming regions. HIFI showed the line was broadened into a double peak, and this allowed the motion of the gas to be fitted with a model.

    Firstly, the team fitted the overall rotation of the galaxy, and then the turbulence in the gas clouds. To their surprise they found that galaxy S0901 was extremely well behaved. Instead of turbulence, it was found to be in orderly rotation, much more akin to the majestic galaxies of today.

    “Usually, when astronomers examine galaxies at this early era, they find that turbulence plays a much greater role than it does in modern galaxies. But S0901 is a clear exception to that pattern, and the Clone could be another,” says Rhoads.

    The Clone, the second galaxy in their study, could also be fitted by an orderly rotation. However, because it was somewhat dimmer, the quality of the data was not so good. This meant that the data could also be fitted with a highly turbulent model, as conventional wisdom would expect.

    clone
    Herschel spectrum of the Clone. Credit: ESA/Herschel/HIFI. Acknowledgments: James Rhoads and Sangeeta Malhotra, Arizona State University, USA

    “Galaxies 10 billion years ago were making stars more actively than they do now,” says Malhotra, “They usually also show more turbulence, likely because they are accumulating gas faster than a modern galaxy does. But here we have cases of early galaxies that combine the ‘calm’ rotation of a modern one with the active star formation of their early peers. This suggests first that these galaxies have finished accumulating their gas, at least for now. But it also seems that turbulence is not actually required to trigger that early, active star formation.”

    Malhotra acknowledges the preliminary nature of their study. “This is not the last word on this. We need a bigger sample to be sure of our conclusions,” she says.

    But that bigger sample will not be investigated by Herschel. As predicted, the liquid helium coolant needed to keep HIFI and Herschel’s other instruments working ran out in April 2013. Instead the researchers hope to continue the work pioneered by Herschel using the Atacama Large Millimeter/submillimeter Array (ALMA), a ground-based array of 66 radio dishes in Chile.

    ALMA Array
    ALMA

    “It is mind-boggling that with Herschel/HIFI – admittedly with the help of gravitational lensing – it has been possible to study the internal gas kinematics in galaxies when the Universe was only a few billion years old, and what we can learn about them this way. This pioneering work by Herschel is bound to be continued,” says Göran Pilbratt, Herschel Project Scientist at ESA.

    Background Information

    The study reported here is based on observations performed with the Heterodyne Instrument for the Far-Infrared (HIFI) on board ESA’s Herschel Space Observatory of SDSS090122.37+181432.3, referred to as S0901, and SDSS J120602.09+514229.5, known as the Clone. The results are published in Herschel Extreme Lensing Line Observations: Dynamics of two strongly lensed star forming galaxies near redshift z = 2, by J. Rhoads et al., to appear in the 2014 May 20 issue of The Astrophysical Journal, volume 787, issue 1.

    Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

    The HIFI instrument is a very high-resolution heterodyne spectrometer and operates in seven bands covering the wavelength range between 157 and 625 µm. HIFI has been designed and built by a consortium of institutes and university departments across Europe, Canada, and the United States under the leadership of SRON Netherlands Institute for Space Research, the Netherlands, with major contributions from Germany, France, and the USA. HIFI Consortium members are: CSA, U. Waterloo (Canada); CESR, LAB, LERMA, IRAM (France); KOSMA, MPIfR, MPS (Germany); NUI Maynooth (Ireland); ASI, IFSI-INAF, Osservatorio Astrofisico di Arcetri-INAF (Italy); SRON, TUD (Netherlands); CAMK, CBK (Poland); Observatorio Astronómico Nacional (IGN), Centro de Astrobiología (CSIC-INTA) (Spain); Chalmers University of Technology – MC2, RSS & GARD, Onsala Space Observatory, Swedish National Space Board, Stockholm University – Stockholm Observatory (Sweden); ETH Zurich, FHNW (Switzerland); Caltech, JPL, NHSC (USA).

    Herschel was launched on 14 May 2009 and completed science observations on 29 April 2013.

    See the full article here.

    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 9:24 am on April 28, 2014 Permalink | Reply
    Tags: , , , , ESA Herschel   

    From ESA: “Glowing jewels in the Galactic Plane” 

    ESASpaceForEuropeBanner
    European Space Agency

    28/04/2014

    The majority of the stars in our Galaxy, the Milky Way, reside in a single huge disc, known as the Galactic Plane, spanning 100 000 light-years across. The Sun also resides in this crowded stellar hub, lying roughly halfway between its centre and its outer edges.

    gp

    This disc is filled with a diffuse mixture of gas and dust – the interstellar medium – that pervades space, filling the large gaps found between stars. Occasionally, these clouds of gas and dust cool, becoming denser and denser until they spark star formation, giving rise to new generations of stars.

    This image is part of Hi-GAL, a survey of the Galactic Plane completed with ESA’s Herschel Space Observatory.

    ESA Herschel
    ESA/Herschel

    Peering at the sky in infrared light, Herschel could detect the glow of dust particles dispersed between stars. This minor – but crucial – component of the interstellar medium allows astronomers to investigate how stars are born in the Milky Way, and how they affect their environment as they age.

    Nestled in the Milky Way’s disc are pockets of gas and dust that have been heated by nearby newborn stars, causing them to glow brightly like cosmic gems. Through their higher temperatures, these regions glow at shorter infrared wavelengths and are depicted in violet and green, while the colder material in the surroundings – only a few tens of degrees above absolute zero – appears redder.

    Laced amongst the stars is an intricate network of filaments sprinkled with tiny white spots: these are denser clumps of gas and dust that will likely evolve and give birth to new stars.

    The image combines observations from the PACS and SPIRE instruments on Herschel. It spans about 12º on the longer side, corresponding to some 24 times the diameter of the full Moon. This is 1/30th of the entire Galactic Plane survey.

    PACS
    PACS

    spire
    SPIRE

    This image was first published in OSHI, the Online Showcase of Herschel Images, in 2011.

    See the full article here.

    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 11:04 am on March 18, 2014 Permalink | Reply
    Tags: , , , , ESA Herschel   

    From ESA/Herschel: “Herschel completes largest survey of cosmic dust in local Universe” 

    ESA Planck
    Planck

    XMM Newton
    XMM-Newton
    herschel
    Herschel

    18 March 2014
    Markus Bauer
    ESA Science and Robotic Exploration Communication Officer
    Tel: +31 71 565 6799
    Mob: +31 61 594 3954
    Email: markus.bauer@esa.int

    Luca Cortese
    Swinburne University of Technology, Australia
    Email: lcortese@swin.edu.su

    Göran Pilbratt
    ESA Herschel Project Scientist
    Tel: +31 71 565 3621
    Email: gpilbratt@rssd.esa.int

    The largest census of dust in local galaxies has been completed using data from ESA’s Herschel space observatory, providing a huge legacy to the scientific community.

    survey

    Cosmic dust grains are a minor but fundamental ingredient in the recipe of gas and dust for creating stars and planets. But despite its importance, there is an incomplete picture of the dust properties in galaxies beyond our own Milky Way.

    Key questions include how the dust varies with the type of galaxy, and how it might affect our understanding of how galaxies evolve.

    hs
    Herschel survey in infrared

    Before concluding its observations in April 2013, Herschel provided the largest survey of cosmic dust, spanning a wide range of nearby galaxies located 50–80 million light-years from Earth.

    The catalogue contains 323 galaxies with varying star formation activity and different chemical compositions, observed by Herschel’s instruments across far-infrared and submillimetre wavelengths.

    A sample of these galaxies is displayed in a collage, arranged from dust-rich in the top left to dust-poor in the bottom right.

    The dust-rich galaxies are typically spiral or irregular, whereas the dust-poor ones are usually elliptical. Blue and red colours represent cooler and warmer regions of dust, respectively.

    visible
    Herschel survey in visible light

    Dust is gently heated across a range of temperatures by the combined light of all of the stars in each galaxy, with the warmest dust being concentrated in regions where stars are being born.

    For comparison, the galaxies are also shown in visible light images obtained by the Sloan Digital Sky Survey. Here, blue corresponds to young stars – hot, massive stars that burn through their fuel very quickly and are therefore short-lived.

    Conversely, red stars are older population – they are less massive and cooler, and therefore live for longer.

    The Herschel observations allow astronomers to determine how much light is emitted by the dust as a function of wavelength, providing a means to study the physical properties of the dust.

    For example, a galaxy forming stars at a faster rate should have more massive, hot stars in it, and thus the dust in the galaxy should also be warmer. In turn, that means that more of the light emitted by the dust should come out at shorter wavelengths.

    However, the data show greater variations than expected from one galaxy to another based on their star formation rates alone, implying that other properties, such as its chemical enrichment, also play an important role.

    By allowing astronomers to investigate these correlations and dependences, the survey provides a much-needed local benchmark for quantifying the role played by dust in galaxy evolution throughout the history of the Universe.

    The data will complement observations being made by other telescopes, such as the ground-based Atacama Large Millimeter Array in Chile, which will allow astronomers to look at dust in galaxies to the very edge of the observable Universe.

    See the full article here.

    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 5:32 pm on January 27, 2014 Permalink | Reply
    Tags: , , , , ESA Herschel,   

    From ESA: “The whirl of stellar life” 

    ESASpaceForEuropeBanner
    European Space Agency

    27/01/2014
    No Writer Credit

    whirlpool

    The Whirlpool Galaxy, also known as M51 or NGC 5194, is one of the most spectacular examples of a spiral galaxy. With two spiral arms curling into one another in a billowing swirl, this galaxy hosts over a hundred billion stars and is currently merging with its companion, the smaller galaxy NGC 5195.

    m51
    M51 with NGC5195 in the upper right (Hubble)

    Around 30 million light-years away, the Whirlpool Galaxy is close enough to be easily spotted even with binoculars. Using the best telescopes available both on the ground and in space, astronomers can scrutinise its population of stars in extraordinary detail.

    In this image, observations performed at three different wavelengths with ESA’s Herschel and XMM-Newton space telescopes are combined to reveal how three generations of stars coexist in the Whirlpool Galaxy.

    ESA Herschel
    Herschel

    ESA XMM Newton
    XMM- Newton

    The infrared light collected by Herschel – shown in red and yellow – reveals the glow of cosmic dust, which is a minor but crucial ingredient in the interstellar material in the galaxy’s spiral arms. This mixture of gas and dust provides the raw material from which the Whirlpool Galaxy’s future generations of stars will take shape.

    Observing in visible and ultraviolet light, astronomers can see the current population of stars in the Whirlpool Galaxy, since stars in their prime shine most brightly at shorter wavelengths than infrared. Seen at ultraviolet wavelengths with XMM-Newton and portrayed in green in this composite image are the galaxy’s fiercest stellar inhabitants: young and massive stars pouring powerful winds and radiation into their surroundings.

    The image also shows the remains of previous stellar generations, which shine brightly in X-rays and were detected by XMM-Newton. Shown in blue, these sources of X-rays are either the sites where massive stars exploded as supernovae in the past several thousand years, or binary systems that host neutron stars or black holes, the compact objects left behind by supernovae.

    See the full article here.

    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 5:32 pm on December 13, 2013 Permalink | Reply
    Tags: , , , , , ESA Herschel   

    From ESA: “Herschel spies active argon in Crab Nebula” 

    ESASpaceForEuropeBanner
    European Space Agency

    12 December 2013
    Michael J. Barlow
    Department of Physics & Astronomy
    University College London
    London, UK
    Email: mjbstar.ucl.ac.uk
    Phone: +44-20-7679-7160
    Mobile: +44-77-5894-5482

    Bruce M. Swinyard
    Department of Physics & Astronomy
    University College London
    London, UK
    Email: bmsstar.ucl.ac.uk; bruce.swinyardstfc.ac.uk
    Phone: +44-20-7679-1352
    Mobile: +44-79-0834-3567

    Göran Pilbratt
    Herschel Project Scientist
    Research and Scientific Support Department
    Science and Robotic Exploration Directorate
    ESA, The Netherlands
    Email: gpilbrattrssd.esa.int
    Phone: +31-71-565-3621

    Using ESA’s Herschel Space Observatory, a team of astronomers has found first evidence of a noble-gas based molecule in space. A compound of argon, the molecule was detected in the gaseous filaments of the Crab Nbula, one of the most famous supernova remnants in our Galaxy. While argon is a product of supernova explosions, the formation and survival of argon-based molecules in the harsh environment of a supernova remnant is an unforeseen surprise.

    crab

    crab2
    Herschel image and spectrum of the Crab Nebula, with emission lines from the molecular ion argon hydride.
    Credit: ESA/Herschel/PACS, SPIRE/MESS Key Programme Supernova Remnant Team

    Just like a group of people, the periodic table of chemical elements has its share of team players and loners. While some elements tend to react more easily with other species, forming molecules and other compounds, others hardly ever take part in chemical reactions and are mainly found in isolation. ‘Inert’ elements par excellence are the noble gases: helium, neon, argon, krypton, xenon and radon.

    PeriodicTable2
    Periodic table of chemical elements

    The name of one of them – argon – derives from the Greek word for idle, to emphasise its highly inert nature. But noble gases are not entirely inactive. While at first scientists doubted that chemical compounds could even contain noble gases, several such species are now known and have been extensively studied in the laboratory.

    Things are more complex in space. Over the decades, astronomers have detected atoms and ions of noble gases in a variety of cosmic environments, ranging from the Solar System to the atmospheres of stars, from dense nebulae to the diffuse interstellar medium. But the search for noble-gas based compounds had until now proved unsuccessful, suggesting that these almost inert elements might have a hard time reacting with other species in space.

    A new study, led by Michael Barlow from University College London, UK, and based on data from ESA’s Herschel Space Observatory, has found the first evidence of such a compound in space. The results are published in the journal Science.

    See the full article here.

    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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    • Spock's Sister 6:42 pm on December 13, 2013 Permalink | Reply

      The words “active argon” piqued my interest. For a moment I thought I had the periodic table completely wrong in my mind. Look forward to hearing more about it.

      Like

    • richardmitnick 8:26 pm on December 13, 2013 Permalink | Reply

      Thanks for your interest and for reading. I generally provide plenty of links for further exploration.

      Like

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