From Universe Today: “Only 10 Light-Years Away, there’s a Baby Version of the Solar System”

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Universe Today

6 May 2017
Matt Williams

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System Epsilon Eridani
Date 27 October 2008
Source http://jpl.nasa.gov/news/news.cfm
Author NASA/JPL-Caltech

Astronomers are understandanly fascinated with the Epsilon Eridani system. For one, this star system is in close proximity to our own, at a distance of about 10.5 light years from the Solar System. Second, it has been known for some time that it contains two asteroid belts and a large debris disk. And third, astronomers have suspected for many years that this star may also have a system of planets.

On top of all that, a new study by a team of astronomers has indicated that Epsilon Eridani may be what our own Solar System was like during its younger days. Relying on NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) aircraft, the team conducted a detailed analysis of the system that showed how it has an architecture remarkably similar to what astronomer believe the Solar System once looked like.

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NASA/DLR SOFIA aircraft before a 2015 flight to observe a nearby star. Credit: Massimo Marengo.

Led by Kate Su – an Associate Astronomer with the Steward Observatory at the University of Arizona – the team includes researchers and astronomers from the Department of Physics & Astronomy of Iowa State University, the Astrophysical Institute and University Observatory at the University of Jena (Germany), and NASA’s Jet Propulsion Laboratory and Ames Research Center.

For the sake of their study – the results of which were published in The Astronomical Journal under the title The Inner 25 AU Debris Distribution in the Epsilon Eri System – the team relied on data obtained by a flight of SOFIA in January 2015. Combined with detailed computer modeling and research that went on for years, they were able to make new determinations about the structure of the debris disk.

As already noted, previous studies of Epsilon Eridani indicated that the system is surrounded by rings made up of materials that are basically leftovers from the process of planetary formation. Such rings consist of gas and dust, and are believed to contain many small rocky and icy bodies as well – like the Solar System’s own Kuiper Belt, which orbits our Sun beyond Neptune.

Kuiper Belt. Minor Planet Center

Careful measurements of the disk’s motion has also indicated that a planet with nearly the same mass as Jupiter circles the star at a distance comparable to Jupiter’s distance from the Sun. However, based on prior data obtained by the NASA’s Spitzer Space Telescope, scientists were unable to determine the position of warm material within the disk – i.e. the dust and gas – which gave rise to two models.

NASA/Spitzer Telescope

In one, warm material is concentrated into two narrow rings of debris that orbit the star at distances corresponding respectively to the Main Asteroid Belt and Uranus in our Solar System. According to this model, the largest planet in the system would likely be associated with an adjacent debris belt. In the other, warm material is in a broad disk, is not concentrated into asteroid belt-like rings, and is not associated with any planets in the inner region.

Using the new SOFIA images, Su and her team were able to determine that the warm material around Epsilon Eridani is arranged like the first model suggests. In essence, it is in at least one narrow belt, rather than in a broad continuous disk. As Su explained in a NASA press release:

“The high spatial resolution of SOFIA combined with the unique wavelength coverage and impressive dynamic range of the FORCAST camera allowed us to resolve the warm emission around eps Eri, confirming the model that located the warm material near the Jovian planet’s orbit. Furthermore, a planetary mass object is needed to stop the sheet of dust from the outer zone, similar to Neptune’s role in our solar system. It really is impressive how eps Eri, a much younger version of our solar system, is put together like ours.”

These observations were made possible thanks to SOFIA’s on-board telescopes, which have a greater diameter than Spitzer – 2.5 meters (100 inches) compared to Spitzer’s 0.85 m (33.5 inches). This allowed for far greater resolution, which the team used to discern details within the Epsilon Eridani system that were three times smaller than what had been observed using the Spitzer data.

In addition, the team made use of SOFIA’s powerful mid-infrared camera – the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). This instrument allowed the team to study the strongest infrared emissions coming from the warm material around the star which are otherwise undetectable by ground-based observatories – at wavelengths between 25-40 microns.

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This artist’s conception of the Epsilon Eridani system, the closest star system who’s structure resembles a young Solar System. Credit: NASA/JPL/Caltech

These observations further indicate that the Epsilon Eridani system is much like our own, albeit in younger form. In addition to having asteroid belts and a debris disk that is similar to our Main Belt and Kuiper Belt, it appears that it likely has more planets waiting to be found within the spaces between. As such, the study of this system could help astronomers to learn things about the history of our own Solar System.

Massimo Marengo, one of he co-authors of the study, is an Associate Professor with the Department of Physics & Astronomy at Iowa State University. As he explained in a University of Iowa press release:

“This star hosts a planetary system currently undergoing the same cataclysmic processes that happened to the solar system in its youth, at the time in which the moon gained most of its craters, Earth acquired the water in its oceans, and the conditions favorable for life on our planet were set.”

At the moment, more studies will need to be conducted on this neighboring stars system in order to learn more about its structure and confirm the existence of more planets. And it is expected that the deployment of next-generation instruments – like the James Webb Space Telescope, scheduled for launch in October of 2018 – will be extremely helpful in that regard.

“The prize at the end of this road is to understand the true structure of Epsilon Eridani’s out-of-this-world disk, and its interactions with the cohort of planets likely inhabiting its system,” Marengo wrote in a newsletter about the project. “SOFIA, by its unique ability of capturing infrared light in the dry stratospheric sky, is the closest we have to a time machine, revealing a glimpse of Earth’s ancient past by observing the present of a nearby young sun.”

See the full article here .

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From Goddard: “Moth’s Eye Inspires Critical Component on SOFIA’s Newest Instrument”

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NASA Goddard Space Flight Center

Dec. 20, 2016 [Never saw this before.]
Lori Keesey
NASA Goddard Space Flight Center

NASA/DLR SOFIA

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These images taken with a scanning electron microscope show details of a new absorber that is enabling observations by the High-Resolution Airborne Wideband Camera-plus, or HAWC+, a new SOFIA instrument. The “spikes” were inspired by the structure of a moth’s eye. Credits: NASA

Nature, and more particularly a moth’s eye, inspired the technology that allows a new NASA-developed camera to create images of astronomical objects with far greater sensitivity than was previously possible.

The idea is simple. When examined close up, a moth’s eye contains a very fine array of small tapered cylindrical protuberances. Their job is to reduce reflection, allowing these nocturnal creatures to absorb as a much light as possible so that they can navigate even in the dark.

The same absorber technology concept, when applied to a far-infrared absorber, results in a silicon structure containing thousands of tightly packed, micro-machined spikes or cylindrical protuberances no taller than a grain of sand. It is a critical component of the four 1,280-pixel bolometer detector arrays that a team of scientists and technologists at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, created for the High-Resolution Airborne Wideband Camera-plus, or HAWC+.

NASA just completed the commissioning of HAWC+ onboard the Stratospheric Observatory for Infrared Astronomy, or SOFIA, a joint venture involving NASA and the German Aerospace Center, or DLR. This heavily-modified 747SP aircraft carries with it an eight-foot telescope and six instruments to altitudes high enough not to be obscured by water in Earth’s atmosphere, which blocks most of the infrared radiation from celestial sources.

The upgraded camera not only makes images, but also measures the polarized light from the emission of dust in our galaxy. With this instrument, scientists will be able to study the early stages of star and planet formation, and, with HAWC+’s polarimeter, map the magnetic fields in the environment around the supermassive black hole at the center of the Milky Way.

With such a system — never before used in astronomy — even minute variations in the light’s frequency and direction can be measured. “This enables the detector to be used over a wider bandwidth. It makes the detector far more sensitive — especially in the far infrared,” said Goddard scientist Ed Wollack, who worked with Goddard detector expert Christine Jhabvala to devise and build the micro-machined absorbers critical to the Goddard-developed bolometer detectors.

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NASA recently completed the commissioning of a new airborne camera on NASA’s SOFIA aircraft. This image shows HAWC+ on SOFIA’s telescope.
Credits: NASA/AFRC

Bolometers are commonly used to measure infrared or heat radiation, and are, in essence, very sensitive thermometers. When radiation is focused and strikes an absorptive element, typically a material with a resistive coating, the element is heated. A superconducting sensor then measures the resulting change in temperature, revealing the intensity of the incident infrared light.

This particular bolometer is a variation of a detector technology called the backshort under-grid sensor, or BUGS, used now on a number of other infrared-sensitive instruments. In this particular application, the reflective optical structures — the so-called backshorts — are replaced with the micro-machined absorbers that stop and absorb the light.

The team had experimented with carbon nanotubes as a potential absorber. However, the cylindrically shaped tubes now used for a variety of spaceflight applications proved ineffective at absorbing far-infrared wavelengths. In the end, Wollack looked to the moth as a possible solution.

“You can be inspired by something in nature, but you need to use the tools at hand to create it,” Wollack said. “It really was the coming together of people, machines, and materials. Now we have a new capability that we didn’t have before. This is what innovation is all about.”

See the full article here.

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NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.


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From SOFIA: “SOFIA Confirms Nearby Planetary System is Similar to Our Own”

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NASA SOFIA

SOFIA (Stratospheric Observatory For Infrared Astronomy)

May 2, 2017
Nick Veronico
nveronico@sofia.usra.edu

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Artist’s illustration of the Epsilon Eridani system showing Epsilon Eridani b. In the right foreground, a Jupiter-mass planet is shown orbiting its parent star at the outside edge of an asteroid belt. In the background can be seen another narrow asteroid or comet belt plus an outermost belt similar in size to our solar system’s Kuiper Belt. The similarity of the structure of the Epsilon Eridani system to our solar system is remarkable, although Epsilon Eridani is much younger than our sun. SOFIA observations confirmed the existence of the asteroid belt adjacent to the orbit of the Jovian planet. Credits: NASA/SOFIA/Lynette Cook

NASA’s flying observatory, the Stratospheric Observatory for Infrared Astronomy, SOFIA, recently completed a detailed study of a nearby planetary system. The investigations confirmed that this nearby planetary system has an architecture remarkably similar to that of our solar system.

Located 10.5 light-years away in the southern hemisphere of the constellation Eridanus, the star Epsilon Eridani, eps Eri for short, is the closest planetary system around a star similar to the early sun. It is a prime location to research how planets form around stars like our sun, and is also the storied location of the Babylon 5 space station in the science fictional television series of the same name.

Previous studies indicate that eps Eri has a debris disk, which is the name astronomers give to leftover material still orbiting a star after planetary construction has completed. The debris can take the form of gas and dust, as well as small rocky and icy bodies. Debris disks can be broad, continuous disks or concentrated into belts of debris, similar to our solar system’s asteroid belt and the Kuiper Belt – the region beyond Neptune where hundreds of thousands of icy-rocky objects reside. Furthermore, careful measurements of the motion of eps Eri indicates that a planet with nearly the same mass as Jupiter circles the star at a distance comparable to Jupiter’s distance from the Sun.

With the new SOFIA images, Kate Su of the University of Arizona and her research team were able to distinguish between two theoretical models of the location of warm debris, such as dust and gas, in the eps Eri system. These models were based on prior data obtained with NASA’s Spitzer space telescope.

NASA/Spitzer Telescope

One model indicates that warm material is in two narrow rings of debris, which would correspond respectively to the positions of the asteroid belt and the orbit of Uranus in our solar system. Using this model, theorists indicate that the largest planet in a planetary system might normally be associated with an adjacent debris belt.

The other model attributes the warm material to dust originating in the outer Kuiper-Belt-like zone and filling in a disk of debris toward the central star. In this model, the warm material is in a broad disk, and is not concentrated into asteroid belt-like rings nor is it associated with any planets in the inner region.

Using SOFIA, Su and her team ascertained that the warm material around eps Eri is in fact arranged like the first model suggests; it is in at least one narrow belt rather than in a broad continuous disk.

These observations were possible because SOFIA has a larger telescope diameter than Spitzer, 100 inches (2.5 meters) in diameter compared to Spitzer’s 33.5 inches (0.85 meters), which allowed the team onboard SOFIA to discern details that are three times smaller than what could be seen with Spitzer. Additionally, SOFIA’s powerful mid-infrared camera called FORCAST, the Faint Object infraRed CAmera for the SOFIA Telescope, allowed the team to study the strongest infrared emission from the warm material around eps Eri, at wavelengths between 25-40 microns, which are undetectable by ground-based observatories.

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Illustration based on Spitzer observations of the inner and outer parts of the Epsilon Eridani system compared with the corresponding components of our solar system. Credits: NASA/JPL/Caltech/R. Hurt (SSC)

“The high spatial resolution of SOFIA combined with the unique wavelength coverage and impressive dynamic range of the FORCAST camera allowed us to resolve the warm emission around eps Eri, confirming the model that located the warm material near the Jovian planet’s orbit,” said Su. “Furthermore, a planetary mass object is needed to stop the sheet of dust from the outer zone, similar to Neptune’s role in our solar system. It really is impressive how eps Eri, a much younger version of our solar system, is put together like ours.”

This study was published in the Astronomical Journal on April 25, 2017.

See the full article here .

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SOFIA is a joint project of NASA and the German Aerospace Center (DLR). The aircraft is based at and the program is managed from NASA Armstrong Flight Research Center’s facility in Palmdale, California. NASA’s Ames Research Center, manages the SOFIA science and mission operations in cooperation with the Universities Space Research Association (USRA) headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart.

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From SETI: “Observations of Ceres indicate that asteroids might be camouflaged”

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SETI Institute

January 18 2017
Science Contact:

Franck Marchis
Email: fmarchis@seti.org

Media contacts:

Nicholas A. Veronico
Email: NVeronico@sofia.usra.edu

Seth Shostak
Tel: 650 960-4530
Email: seth@seti.org

The appearance of small bodies in the outer solar system could be deceiving. Asteroids and dwarf planets may be camouflaged with an outer layer of material that actually comes from somewhere else.

Using data primarily gathered by SOFIA, NASA’s Stratospheric Observatory for Infrared Astronomy, a team of astronomers has detected the presence of substantial amounts of material on the surface of Ceres that appears to be fragments of other asteroids.

NASA/DLR SOFIA
NASA/DLR SOFIA

This is contrary to the currently accepted surface composition classification of Ceres, suggesting that the largest body in the asteroid belt between Mars and Jupiter is cloaked by material that has partially disguised its real makeup.

“We find that the outer few microns of the surface is partially coated with dry particles,” says Franck Marchis, senior planetary astronomer at the SETI Institute. “But they don’t come from Ceres itself. They’re debris from asteroid impacts that probably occurred tens of millions of years ago.”

Ceres is considered to be both an asteroid and a dwarf planet, the only dwarf planet located in the inner solar system.

Ceres with bright spot ESO Harps
Ceres with bright spot ESO Harps

Astronomers have classified Ceres, as well as 75 percent of all asteroids, as belonging to composition class “C” based on their similar colors. But the mid-infrared spectra from SOFIA show that Ceres differs substantially from C-type asteroids in nearby orbits, challenging the conventional understanding of the relationship between Ceres and smaller asteroids.

“By analyzing the spectral properties of Ceres we have detected a layer of fine particles of a dry silicate called pyroxene. Models of Ceres based on data collected by NASA’s Dawn…

NASA/Dawn Spacecraft
NASA/Dawn Spacecraft

…as well as ground-based telescopes indicated substantial amounts of water-bearing minerals such as clays and carbonates,” explains Pierre Vernazza, research scientist in the Laboratoire d’Astrophysique de Marseille. “Only the mid-infrared observations made using SOFIA were able to show that both types of material are present on the surface of Ceres.”

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Ceres’ surface is contaminated by a significant amount of dry material while its the area below the crust contains essentially water-bearing materials. The mid-infrared observations revealed the presence of dry pyroxene on the surface probably coming from interplanetary dust particles. The Internal structure of the Dwarf Planet Ceres was derived from the NASA Dawn spacecraft data. No image credit.

To identify where the pyroxene on the surface of Ceres came from, Vernazza and his collaborators, including researchers from the SETI Institute and NASA’s Jet Propulsion Laboratory, turned to interplanetary dust particles (IDPs) that are commonly seen as meteors when they streak through Earth’s atmosphere. The research team had previously shown that IDPs blasted into space by asteroid collisions are an important source of material accumulated on the surfaces of other asteroids. The implication is that a coating of IDPs has caused Ceres to mimic the coloration of some of its dry and rocky neighbors.

Ceres and asteroids are not the only instance in which material transported from elsewhere has affected the surfaces of solar system bodies. Dramatic examples include the red material seen by New Horizons on Pluto’s moon Charon and Saturn’s two-faced moon Iapetus.

NASA/New Horizons spacecraft
NASA/New Horizons spacecraft

Planetary scientists also hypothesize that material from comets and asteroids provided a final veneer to the then-forming Earth – a coating that included substantial amounts of water plus the organic substances of the biosphere.

This study [The Astronomical Journal] resolves a long standing question about whether surface material accurately reflects the intrinsic composition of an asteroid. These results show that by extending observations to the mid-infrared, one can better identify the composition of an asteroid. According to Vernazza, “the detection of some ammoniated clays mixed with the watery clays on Ceres raises the possibility that the dwarf planet might have formed in the outer reaches of the solar system and somehow migrated to its current location.”

See the full article here .

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From SOFIA: “SOFIA Sees Super-Heated Gas Streams Churning up Possible Storm of New Stars”

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SOFIA (Stratospheric Observatory For Infrared Astronomy)

Dec. 8, 2016
No writer credit
Editor: Kassandra Bell

Scientists on board NASA’s flying telescope, the Stratospheric Observatory for Infrared Astronomy, or SOFIA, caught sight of roiling material streaming from a newly formed star, which could spark the birth of a new generation of stars in the surrounding gas clouds.

Many stars in the early stages of formation expel large amounts of super-heated material in two streams, known as bipolar outflows or jets, which flow in opposite directions. A team of scientists led by Bertrand Lefloch from the University of Grenoble Alpes, France, observed these jets coming from Cepheus E, a massive protostar at the earliest stage of star formation, located 2,400 light years from Earth in the constellation Cepheus. Lefloch’s team is studying how such outflows originate and the effects those jets have on star formation in the surrounding clouds.

“The SOFIA observations have unveiled new clues to how these jets powered by protostars actually form, and clarified the physical conditions reigning in these objects,” Lefloch said. Lefloch’s team has determined that the jets are less than 1,000 years old, making this process astronomically very young. The powerful jets are shown to extend out to a distance of 118 billion miles and the jet material is moving at speeds between 200,000 and 300,000 mph.

The team’s observations were made using SOFIA’s Upgraded German Receiver at Terhertz Frequencies, upGREAT, to make a map of the hottest and densest portions of the matter ejected from Cepheus E. The researchers identified three main parts of the outflow: the jet itself, regions of the surrounding gas and dust cloud through which the jets have plowed through, and the shock waves at the farthest ends of the jets affecting the surrounding cloud.

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Map of Cepheus E emphasizing the jets of material flowing to the upper left and lower right from the protostar. The protostar itself is the central yellow-red ‘blob” in the colored background map of hydrogen emission made at a wavelength of 4.5 microns by the Spitzer infrared space telescope. The contour curves show the strength of emission from cool carbon monoxide gas measured by the Plateau de Bure radio telescope located in the French Alps. Lefloch et al. used GREAT on SOFIA to measure the amount and velocity of hot carbon monoxide gas at multiple positions along both “wings” of the outflow jet. Credits: Lefloch et al. 2015 Figure 1

The last area is of particular interest, in that it could be the future birthplace of additional stars. The formation of new stars is thought to be triggered by these shocks. The team was able to map the hottest material because of the unique wavelength range available to SOFIA and the upGREAT instrument. The maps also contained more detail than other observatories because of the size of SOFIA’s telescope.

“The upGREAT instrument now has more detectors, allowing us to make more detailed maps of celestial gas molecules very rapidly,” said Universities Space Research Association’s SOFIA Science Mission Director Harold Yorke. “The physical conditions in the outflowing gas are still poorly known, and we are just now employing new instruments enabling us to study this process. These observations demonstrate that SOFIA is a powerful tool to map the areas around star-forming regions, providing data that are helping to develop a more comprehensive picture of star formation.”

Astronomers are excited about these SOFIA observations because they provide high-resolution data that are complemented by observations conducted by ground and space-based telescopes, including the Atacama Large Millimeter Array, ALMA, and the Herschel Space Observatory.

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

ESA/Herschel spacecraft
ESA/Herschel spacecraft

Results from the Le Floch team’s observations were published in the journal Astronomy and Astrophysics. Further investigations of this target will be necessary to definitively determine how this violent activity impacts star formation.

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SOFIA is a joint project of NASA and the German Aerospace Center (DLR). The aircraft is based at and the program is managed from NASA Armstrong Flight Research Center’s facility in Palmdale, California. NASA’s Ames Research Center, manages the SOFIA science and mission operations in cooperation with the Universities Space Research Association (USRA) headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart.

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From Gemini: “Are All Stars Created Equal?”

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Gemini Observatory
Gemini Observatory

November 14, 2016
Science Contacts:

Alessio Caratti o Garatti
Dublin Institute for Advanced Studies
Email: alessio”at”cp.dias.ie
Office: +353 1 4406656 ext.342
Cell: +353 87 1091628

Bringfried Stecklum
Thüringer Landessternwarte Tautenburg
Email: stecklum”at”tls-tautenburg.de
Office: +49 36427 863
Cell: +49 179 38088401

Media Contact:

Peter Michaud
Gemini Observatory
Hilo, Hawai‘i
Email: pmichaud”at”gemini.edu
Cell: (808) 936-6643

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Artist’s impression of an accretion burst in a high-mass young stellar object like S255 NIRS 3. Image Credit: Deutsches SOFIA Institut (DSI)

Astronomers using critical observations from the Gemini Observatory have found the strongest evidence yet that the formation of more massive stars follow a path similar to their lower-mass brethren – but on steroids!

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Pre-outburst (left) and outburst (middle) near-infrared images (K, H, J bands) of the high-mass young stellar object S255IR NIRS 3, taken
from 2009 UKIDSS archive data and the PANIC camera (Calar Alto Observatory, Man-Planck Society) in 2016, respectively, as well as
outburst mid-infrared images (right) taken with FORCAST / SOFIA at 7.7, 19.7 and 31.5 microns (2016). Copyright: Caratti o Garatti.

The new findings, that include data from Gemini, SOFIA, Calar Alto, and the European Southern Observatory, show that the episodic explosive outbursts within what are called accretion disks, known to occur during the formation of average mass stars like our Sun, also happen in the formation of very massive stars.

“These outbursts, which are several orders of magnitude larger than their lower mass siblings, can release about as much energy as our Sun delivers in over 100,000 years,” said Dr. Alessio Caratti o Garatti of the Dublin Institute for Advanced Studies (Ireland). “Surprisingly, fireworks are observed not just at the end of the lives of massive stars, as supernovae, but also at their birth!”

The international team of astronomers (led by Caratti o Garatti) published their work in the November 14th issue of the journal Nature Physics, presenting the first clear case that massive stars can form from clumpy disks of material – in much the same way as less massive stars. Previously it was thought that the accretion disks seen around lower mass stars would not survive around stars of higher mass due to their strong radiation pressure. Therefore, some other process would be necessary to account for the existence of more massive stars – which can exceed 50-100 times the mass of our Sun.

“How accretion disks can survive around these massive stars is still a mystery, but the Gemini spectroscopic observations show the same fingerprints we see in lower mass stars,” said Caratti o Garatti. “Probably the accretion bursts reduce the radiation pressure of the central source and allow the star to form, but we still have a lot of explaining to do in order to account for these observations.”

According to team member Dr. Bringfried Stecklum of the Thüringer Landessternwarte Tautenburg (Germany), “Studying the formation of high-mass stars is challenging because they are relatively rare and deeply embedded in their natal cloud, thus not visible in optical, or visible, light. This is why we need infrared instruments like the Near-infrared Integral Field Spectrograph (NIFS) at Gemini North on Maunakea in Hawai‘i.” The outburst events are also very rapid, probably lasting only a few years or less – which, for a star, is the blink of an eye, adding to their rarity.

“The birth of truly massive stars has been a mystery that astronomers have been studying for decades. Only now, with large, infrared-optimized telescopes like Gemini, are we able to probe the details of this short-lived and, now it seems, rather explosive process,” notes Chris Davis, Program Director at the National Science Foundation which supports the operation of the Gemini Observatory and the development of its instruments. “These NIFS observations represent yet another coup for the Gemini Observatory.”

The developing star observed in this study, S255IR NIRS 3, is relatively distant, some 6,000 light years away, with a mass estimated at about 20 times the mass of our Sun. The Gemini observations reveal that the source of the explosive outburst is a huge clump of gas, probably about twice the mass of Jupiter, accelerated to supersonic speeds and ingested by the forming star. The team estimates that the outburst began about 16 months ago and according to Caratti o Garatti it appears that the outburst is still active, but much weaker.

“While low-mass stars, and possible planetary systems, can form basically next door to our Sun, the formation of high-mass stars is a complex and relatively rapid process that tends to happen rather far away in our galaxy, thousands, or even tens of thousands of light years away,” said Caratti o Garatti. He adds that the formation of these massive stars happens on timescales of 100,000 years, whereas it takes hundreds of times longer for lower mass stars like our Sun to form. “When we study the formation of higher mass stars it’s like watching a timelapse move when compared to less massive stars, although the process for massive stars is fast and furious, it still takes tens of thousands of years!”

“While this research presents the strongest case yet for similar formation processes for low and high mass stars, there is still lots to understand,” concludes Stecklum. “Especially whether planets can form in the same way around stars at both ends of the mass spectrum.”

Original Publication:
Disk-mediated accretion burst in a high-mass young stellar object, A. Caratti o Garatti, B. Stecklum, R. Garcia Lopez, J. Eislöffel, T. P. Ray, A. Sanna, R. Cesaroni, C. M.Walmsley, R. D. Oudmaijer,W. J. deWit, L. Moscadelli, J. Greiner, A. Krabbe, C. Fischer, R. Klein and J. M. Ibañez , Nature Physics Journal Nov. 14 th 2016, DOI: 10.1038/NHPYS3942.

See the full article here .

Deutsches SOFIA Institute Release

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Gemini North
Gemini North, Hawai’i

Gemini South
Gemini South, Chile
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Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

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From SOFIA: “SOFIA Detects Collapsing Clouds Becoming Young Suns”

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NASA SOFIA

SOFIA (Stratospheric Observatory For Infrared Astronomy)

Oct. 5, 2016
Point of Contact Nicholas A. Veronico
NVeronico@sofia.usra.edu
SOFIA Science Center NASA Ames Research Center, Moffett Field, California

1
An infrared image of the W43 star-forming region located 20,000 light years away in the direction of the constellation Aquila, one of the places where Wyrowski et al. detected cloud clumps collapsing to become massive stars. Credits: NASA/JPL-Caltech/2MASS

Researchers on board NASA’s Stratospheric Observatory for Infrared Astronomy, SOFIA, observed the collapse of portions of six interstellar clouds on their way to becoming new stars that will be much larger than our sun.

When a gas cloud collapses on itself, the cloud’s own gravity causes it to contract and the contraction produces heat friction. Heat from the contraction eventually causes the core to ignite hydrogen fusion reactions creating a star.

Astronomers are excited about this SOFIA research because there have been very few previous direct observations of collapse motion. These SOFIA observations have enabled scientists to confirm theoretical models about how interstellar clouds collapse to become stars and the pace at which they collapse. Actually observing this collapse, called “infall,” is extremely challenging because it happens relatively quickly in astronomical terms.

“Detecting infall in protostars is very difficult to observe, but is critical to confirm our overall understanding of star formation,” said Universities Space Research Association’s Erick Young, SOFIA Science Mission Operations director.

Using the observatory’s GREAT instrument, the German Receiver for Astronomy at Terahertz Frequencies, scientists searched for this developmental stage in nine embryonic stars, called protostars, by measuring the motions of the material within them. They found that six of the nine protostars were actively collapsing, adding substantially to the previous list of less than a dozen protostars directly determined to be in this infall stage.

For several weeks each year, the SOFIA team operates from Christchurch, New Zealand, to study objects best observed from southern latitudes, including the complete center of the Milky Way where many star-forming regions are located. Heading south during the Southern Hemisphere’s winter months, when the nights are long and infrared-blocking water vapor is especially low, also creates prime observing conditions.

“With the Southern Hemisphere deployments of SOFIA, the full inner Milky Way comes into reach for star formation studies. This is crucial for observations of the earliest phases of high-mass star formation, since this is a relatively rapid and rare event,” said Friedrich Wyrowski, astronomer at the Max-Planck Institute for Radio Astronomy in Bonn, Germany.

The results were from observations made in the Southern Hemisphere in 2015, and were published in Astronomy and Astrophysics earlier this year. SOFIA spent seven weeks during 2016 observing from Christchurch. The scientific teams involved in the Southern Hemisphere observations are analyzing the acquired data now.

See the full article here .

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SOFIA is a joint project of NASA and the German Aerospace Center (DLR). The aircraft is based at and the program is managed from NASA Armstrong Flight Research Center’s facility in Palmdale, California. NASA’s Ames Research Center, manages the SOFIA science and mission operations in cooperation with the Universities Space Research Association (USRA) headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart.

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#astronomy, #basic-research, #nasa-sofia, #sofia-detects-collapsing-clouds-becoming-young-suns