Astronomers Detect Whirlpool Movement in Early Galaxies

ALMA images of rotating galaxies in the early universe shown on a background from the Hubble Space Telescope. Credit: Hubble (NASA/ESA), ALMA (ESO/NAOJ/NRAO), P. Oesch (University of Geneva) and R. Smit (University of Cambridge)

Artist impression of a rotating galaxy in the early universe.

Credit: Institute of Astronomy, Amanda Smith

Astronomers have looked back to a time soon after the Big Bang, and have discovered swirling gas in some of the earliest galaxies to have formed in the Universe. These ‘newborns’ – observed as they appeared nearly 13 billion years ago – spun like a whirlpool, similar to our own Milky Way.

An international team led by Renske Smit from the Kavli Institute of Cosmology at the University of Cambridge used the Atacama Large Millimeter/submillimeter Array (ALMA) to open a new window onto the distant Universe, and have identified normal star-forming galaxies at a very early stage in cosmic history. The results are reported in the journal Nature, and will be presented at the 231^st meeting of the American Astronomical Society.

Light from distant objects takes time to reach Earth, so observing objects that are billions of light years away enables us to look back in time and directly observe the formation of the earliest galaxies. The Universe at that time, however, was filled with an obscuring “haze” of neutral hydrogen gas, which makes it difficult to see the formation of the very first galaxies with optical telescopes.

Smit and her colleagues used ALMA to observe two small newborn galaxies, as they existed just 800 million years after the Big Bang. By analyzing the spectral ‘fingerprint’ of the far-infrared light collected by ALMA, they were able to establish the distance to the galaxies and, for the first time, see the internal motion of the gas that fueled their growth.

“Until ALMA, we’ve never been able to see the formation of galaxies in such detail, and we’ve never been able to measure the movement of gas in galaxies so early in the Universe’s history,” said co-author Stefano Carniani, from Cambridge’s Cavendish Laboratory and Kavli Institute of Cosmology.

The researchers found that the gas in these newborn galaxies swirled and rotated in a whirlpool motion, similar to our own galaxy and other, more mature galaxies much later in the Universe’s history. Despite their relatively small size – about five times smaller than the Milky Way – these galaxies were forming stars at a higher rate than other young galaxies, but the researchers were surprised to discover that the galaxies were not as chaotic as expected.

“In the early Universe, gravity caused gas to flow rapidly into the galaxies, stirring them up and forming lots of new stars – violent supernova explosions from these stars also made the gas turbulent,” said Smit, who is a Rubicon Fellow at Cambridge, sponsored by the Netherlands Organisation for Scientific Research. “We expected that young galaxies would be dynamically ‘messy’, due to the havoc caused by exploding young stars, but these mini-galaxies show the ability to retain order and appear well regulated. Despite their small size, they are already rapidly growing to become one of the ‘adult’ galaxies like we live in today.”

The data from this project on small galaxies paves the way for larger studies of galaxies during the first billion years of cosmic time.

The research was funded in part by the European Research Council and the UK Science and Technology Facilities Council (STFC).

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

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The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) in Taiwan and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

Source:  National Radio Astronomy Observatory (NRAO)

CTA in the Era of Multi-Messenger Astrophysics

Artist’s illustration of the recent merger of a binary neutron star system emitting gravitational waves and creating a gamma-ray ray burst and a kilonova. Credit: NASA’s Goddard Space Flight Center/CI Lab

After years of preparation, a fundamentally new domain of astronomy and astrophysics has shown its first results: multi-messenger astrophysics. Throughout the past decade, several new astrophysical messengers have provided us with new insights into the most violent phenomena in the Universe: starting with high-energy gamma rays, the detection of an astrophysical flux of high-energy neutrinos and the first direct detection of gravitational waves. Building on these significant breakthroughs, many high-energy astrophysics observatories and groups started to work towards a dream that is now coming true: multi-messenger astrophysics, which, via the exchange and combination of data from very different observatories and messengers, opens new windows and provides unprecedented insights into the most violent phenomena ever observed.

The most striking example illustrating the viability of this approach is the detection of electromagnetic signals complementing gravitational waves from the merger of a binary neutron star system. This event, named GW170817, is probably the best-covered astrophysical phenomenon in recent history. Thanks to the huge effort by observatories around the world, it provides for the first time an observational link between binary mergers, short gamma-ray bursts and optical emissions known as kilonovae, and resolves the origin of heavy elements in the Universe [1]. As a hint for the expected CTA performance, H.E.S.S. was the first ground-based instrument to observe the region covering the source region, including the kilonova named SSS17a/AT2017gfo. No high-energy gamma-ray emission could be detected during an extensive observation campaign covering timescales from a few hours to several days after the gravitational wave event [2].

The image below illustrates the simulated response of CTA follow-up observations of the gravitational wave event GW170817. Thanks to the large field-of-view of CTA, only two individual pointings would be necessary to cover most of the localization region provided by the LIGO and VIRGO gravitational wave interferometers (coloured region). Combined with its high sensitivity, CTA will therefore be able to efficiently search for associated high-energy gamma-ray emission.

Credit: F. Schüssler, IRFU/CEA Paris-Saclay

This very recent example just scratches the surface of the enormous potential of these searches. It is all made possible through the rapid exchange of information across very different instruments and the subsequent joint data analyses. These collaborations build on a long history in astronomy of telescopes at far corners of the Earth jointly monitoring variable objects as the globe rotates. The real-time exchange of information in the study of gamma-ray bursts was introduced in the late 1990s. It is this culture of open data and fast information exchange that will ensure the success of multi-messenger astrophysics.

CTA, with its large field-of-view, extremely fast reaction to alerts and very-high sensitivity, is well suited to lead this revolution. The follow-up observations of gravitational wave events have been assigned the highest priority in CTA’s key science project on transient phenomena. Based on the significant experiences gained with H.E.S.S., MAGIC and VERITAS, preparations for these technically challenging observations are well underway.

References:

[1] B.P. Abbott, et al., Multi-messenger Observations of a Binary Neutron Star Merger, Astrophys. J. Letters 848 (2017) L12.

[2] H. Abdalla et al. (H.E.S.S. Collaboration), TeV Gamma-Ray Observations of the Binary Neutron Star Merger GW170817 with H.E.S.S., Astrophys. J. Letters 850 (2017) L22 .

Written by: Fabian Schüssler

Source:  Cherenkov Telescope Array Observatory (CTA)

Exocomets

An image of Halley's comet. Astronomers have detected around other stars exocomets with masses comparable to Halley's comet.W. Liller, the International Halley Watch Large Scale Phenomena Network. Hi-res image

There are currently over 3500 confirmed exoplanets known thanks to the remarkable sensitivity of the Kepler spacecraft and to technological advances in space and ground-based methods made over the past dozen years. Relatively little is known, however, about the minor bodies that might orbit within these systems, asteroids and comets for example. Planet-formation theories predict that such minor bodies should be common, but their low masses and small radii present extreme detection challenges. Methods that rely on solid body transits or velocity variations are generally orders-of-magnitude too weak to spot such small objects. The smallest solid body that has been detected so far via the transit method is an object about one-quarter the size of the Earth, while pulsar timing measurements have spotted a lunar-mass object orbiting a pulsar.

In a tour de force analysis of the Kepler data sets spanning 201250 target stars, CfA astronomers Andrew Vanderburg, Dave Latham, and Allyson Bieryla joined eight of their colleagues in discovering and modeling a likely set of six transiting comets around one star, with another comet possible around a second star. The physical characteristic that made these detections possible was unexpected: the comets have large, extended dust tails that can block enough starlight to make themselves recognizable via unique, asymmetrically shaped absorption dips in their transit lightcurves. (The paper reports, in press, finding a prediction of just such an effect published in 1999). The astronomers systematically consider other explanations for the dips, including starspots, as well as possible inconsistencies in their cometary model, like orbital behavior, but reject them all.

The scientists can estimate the mass of the comets from the observed transit properties and simple assumptions, and they conclude that the bodies are probably similar in mass to Halley's Comet. The scientists also conclude that exocomets are probably not rare given that these seven were spotted without using sophisticated computer tools, although deeper searches will need to be undertaken to find them. Since the two stars hosting exocomets in their study are quite similar in type, they conclude by wondering whether comet transits happen preferentially around certain kinds of stars, although why this might be is not known.

Reference(s): 
 

"Likely Transiting Exocomets Detected by Kepler," S. Rappaport, A. Vanderburg, T. Jacobs, D. LaCourse, J. Jenkins, A. Kraus, A. Rizzuto, D. W. Latham, A. Bieryla, M. Lazarevic, and A. Schmitt, MNRAS 474, 1453, 2018.

Source: Smithsonian Astrophysical Observatory (SAO)

Neutron-star merger yields new puzzle for astrophysicists

GW170817 - NGC 4993
Credit: NASA/CXC/McGill University/J. Ruan et al.

The afterglow from the distant neutron-star merger detected last August has continued to brighten – much to the surprise of astrophysicists studying the aftermath of the massive collision that took place about 138 million light years away and sent gravitational waves rippling through the universe.

New observations from NASA's orbiting Chandra X-ray Observatory, reported in Astrophysical Journal Letters, indicate that the gamma ray burst unleashed by the collision is more complex than scientists initially imagined.

"Usually when we see a short gamma-ray burst, the jet emission generated gets bright for a short time as it smashes into the surrounding medium – then fades as the system stops injecting energy into the outflow," says McGill University astrophysicist Daryl Haggard, whose research group led the new study. "This one is different; it's definitely not a simple, plain-Jane narrow jet."

Cocoon theory

The new data could be explained using more complicated models for the remnants of the neutron star merger. One possibility: the merger launched a jet that shock-heated the surrounding gaseous debris, creating a hot 'cocoon' around the jet that has glowed in X-rays and radio light for many months.

The X-ray observations jibe with radio-wave data reported last month by another team of scientists, which found that those emissions from the collision also continued to brighten over time.

While radio telescopes were able to monitor the afterglow throughout the fall, X-ray and optical observatories were unable to watch it for around three months, because that point in the sky was too close to the Sun during that period. "When the source emerged from that blind spot in the sky in early December, our Chandra team jumped at the chance to see what was going on," says John Ruan, a postdoctoral researcher at the McGill Space Institute and lead author of the new paper. "Sure enough, the afterglow turned out to be brighter in the X-ray wavelengths, just as it was in the radio."

Physics puzzlev

That unexpected pattern has set off a scramble among astronomers to understand what physics is driving the emission. "This neutron-star merger is unlike anything we've seen before," says Melania Nynka, another McGill postdoctoral researcher. "For astrophysicists, it's a gift that seems to keep on giving." Nynka also co-authored the new paper, along with astronomers from Northwestern University and the University of Leicester.

The neutron-star merger was first detected on Aug. 17 by the U.S.-based Laser Interferometer Gravitational-Wave Observatory (LIGO). The European Virgo detector and some 70 ground- and space-based observatories helped confirm the discovery.

The discovery opened a new era in astronomy. It marked the first time that scientists have been able to observe a cosmic event with both light waves -- the basis of traditional astronomy -- and gravitational waves, the ripples in space-time predicted a century ago by Albert Einstein's general theory of relativity. Mergers of neutron stars, among the densest objects in the universe, are thought to be responsible for producing heavy elements such as gold, platinum, and silver.

"Brightening X-ray Emission from GW170817/GRB170817A: Further Evidence for an Outflow," John J. Ruan et al, Astrophysical Journal Letters, Jan. 18, 2018. https://doi.org/10.3847/2041-8213/aaa4f3

Funding for the research was provided by the National Sciences and Engineering Research Council of Canada, the Fonds de recherche du Québec – Nature et technologies, the McGill Trottier Chair in Astrophysics and Cosmology, and the Canadian Institute for Advanced Research.

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Media contacts:

Daryl Haggard
Assistant Professor of Physics
McGill University/McGill Space Institute
daryl.haggard@mcgill.ca

Chris Chipello
Media Relations
McGill University
514-398-4201
christopher.chipello@mcgill.ca

Source: NASA’s Chandra X-ray Observatory/Press Room

Hubble views a supermassive black hole burping — twice

SDSS J1354+1327, SDSS J1354+1328

Credit: NASA, ESA, and J. Comerford (University of Colorado-Boulder)

Researchers using a suite of telescopes including the NASA/ESA Hubble Space Telescope have spotted a supermassive black hole blowing huge bubbles of hot, bright gas — one bubble is currently expanding outwards from the black hole, while another older bubble slowly fades away. This cosmic behemoth sits within the galaxy at the bottom of this image, which lies 900 million light-years from Earth and is known as SDSS J1354+1327. The upper, larger, galaxy is known as SDSS J1354+1328.

Supermassive which can have a mass equivalent to billions of suns, are found in the centre of most galaxies (including the Milky Way). These black holes are able to “feed” on their surroundings, causing them to shine brilliantly as Active Galactic Nuclei (AGN). However, this feeding process is not continuous as it depends on how much matter is available for the black hole to consume; if the surrounding material is clumpy and irregular, an AGN can be seen turning “off” and “on”, and flickering over long cosmic timescales.

This clumpy accretion is what scientists believe has happened with the black hole in SDSS J1354+1327. Scientists believe these two outflows of material are the result of the black hole burping out material after two different feeding events. The first outburst created the fading southern relic: a cone of gas measuring 33 000 light-years across. Around 100 000 years later, a second burst spawned the more compact and radiant outflow emanating from the top of the galaxy: a cone of shocked gas some 3300 light-years across.

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Link

• NASA release

Source: ESA/Hubble/Potw

NASA Team Studies Middle-aged Sun by Tracking Motion of Mercury

Mercury’s proximity to the Sun and small size make it exquisitely sensitive to the dynamics of the Sun and its gravitational pull. 
Credits: NASA/SDO

Like the waistband of a couch potato in midlife, the orbits of planets in our solar system are expanding. It happens because the Sun’s gravitational grip gradually weakens as our star ages and loses mass. Now, a team of NASA and MIT scientists has indirectly measured this mass loss and other solar parameters by looking at changes in Mercury’s orbit.

The new values improve upon earlier predictions by reducing the amount of uncertainty. That’s especially important for the rate of solar mass loss, because it’s related to the stability of G, the gravitational constant. Although G is considered a fixed number, whether it’s really constant is still a fundamental question in physics.

“Mercury is the perfect test object for these experiments because it is so sensitive to the gravitational effect and activity of the Sun,” said Antonio Genova, the lead author of the study published in Nature Communications and a Massachusetts Institute of Technology researcher working at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

The study began by improving Mercury’s charted ephemeris — the road map of the planet’s position in our sky over time. For that, the team drew on radio tracking data that monitored the location of NASA’s MESSENGER spacecraft while the mission was active. Short for Mercury Surface, Space Environment, Geochemistry, and Ranging, the robotic spacecraft made three flybys of Mercury in 2008 and 2009 and orbited the planet from March 2011 through April 2015. The scientists worked backward, analyzing subtle changes in Mercury’s motion as a way of learning about the Sun and how its physical parameters influence the planet’s orbit.

NASA and MIT scientists analyzed subtle changes in Mercury’s motion to learn about the Sun and how its dynamics influence the planet’s orbit. The position of Mercury over time was determined from radio tracking data obtained while NASA’s MESSENGER mission was active. Credits: NASA's Goddard Space Flight Center

For centuries, scientists have studied Mercury’s motion, paying particular attention to its perihelion, or the closest point to the Sun during its orbit. Observations long ago revealed that the perihelion shifts over time, called precession. Although the gravitational tugs of other planets account for most of Mercury’s precession, they don’t account for all of it.

The second-largest contribution comes from the warping of space-time around the Sun because of the star’s own gravity, which is covered by Einstein’s theory of general relativity. The success of general relativity in explaining most of Mercury’s remaining precession helped persuade scientists that Einstein’s theory was right.

Other, much smaller contributions to Mercury’s precession, are attributed to the Sun’s interior structure and dynamics. One of those is the Sun’s oblateness, a measure of how much it bulges at the middle — its own version of a “spare tire” around the waist — rather than being a perfect sphere. The researchers obtained an improved estimate of oblateness that is consistent with other types of studies.

The researchers were able to separate some of the solar parameters from the relativistic effects, something not accomplished by earlier studies that relied on ephemeris data. The team developed a novel technique that simultaneously estimated and integrated the orbits of both MESSENGER and Mercury, leading to a comprehensive solution that includes quantities related to the evolution of Sun’s interior and to relativistic effects.

“We’re addressing long-standing and very important questions both in fundamental physics and solar science by using a planetary-science approach,” said Goddard geophysicist Erwan Mazarico. “By coming at these problems from a different perspective, we can gain more confidence in the numbers, and we can learn more about the interplay between the Sun and the planets.”

The team’s new estimate of the rate of solar mass loss represents one of the first times this value has been constrained based on observations rather than theoretical calculations. From the theoretical work, scientists previously predicted a loss of one-tenth of a percent of the Sun’s mass over 10 billion years; that’s enough to reduce the star’s gravitational pull and allow the orbits of the planets to spread by about half an inch, or 1.5 centimeters, per year per AU (an AU, or astronomical unit, is the distance between Earth and the Sun: about 93 million miles).

The new value is slightly lower than earlier predictions but has less uncertainty. That made it possible for the team to improve the stability of G by a factor of 10, compared to values derived from studies of the motion of the Moon.

“The study demonstrates how making measurements of planetary orbit changes throughout the solar system opens the possibility of future discoveries about the nature of the Sun and planets, and indeed, about the basic workings of the universe,” said co-author Maria Zuber, vice president for research at MIT.

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By Elizabeth Zubritsky
NASA's Goddard Space Flight Center, Greenbelt, Md.

Editor: Rob Garner

Source: NASA/Mercury(Planet)

Odd Behaviour of Star Reveals Lonely Black Hole Hiding in Giant Star Cluster

PR Image eso1802b

Hubble image of the globular star cluster NGC 3201 (annotated)

PR Image eso1802b

Hubble image of the globular star cluster NGC 3201 (annotated)

PR Image eso1802c

Wide-field image of the sky around the globular star cluster NGC 3201 

PR Image eso1802d

The globular cluster NGC 3201

PR Image eso1802e

Hubble image of the globular star cluster NGC 3201 (unannotated)

  PR Image eso1802f

The globular cluster NGC 3201 in the constellation of Vela (The Sails)

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Video

PR Video eso1802a

ESOcast 146 Light: Odd Behaviour of Star Reveals Black Hole in Giant Star Cluster (4K UHD)

PR Video eso1802b

Zooming in on the globular star cluster NGC 3201

PR Video eso1802c

Artist’s impression video of the black hole binary system in NGC 3201

PR Video eso1802d

Artist’s impression video of the black hole binary system in NGC 3201

PR Video eso1802e

Artist’s impression video of the black hole binary system in NGC 3201

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Astronomers using ESO’s MUSE instrument on the Very Large Telescope in Chile have discovered a star in the cluster NGC 3201 that is behaving very strangely. It appears to be orbiting an invisible black hole with about four times the mass of the Sun — the first such inactive stellar-mass black hole found in a globular cluster and the first found by directly detecting its gravitational pull. This important discovery impacts on our understanding of the formation of these star clusters, black holes, and the origins of gravitational wave events.

Globular star clusters are huge spheres of tens of thousands of stars that orbit most galaxies. They are among the oldest known stellar systems in the Universe and date back to near the beginning of galaxy growth and evolution. More than 150 are currently known to belong to the Milky Way.

One particular cluster, called NGC 3201 and situated in the southern constellation of Vela (The Sails), has now been studied using the MUSE instrument on ESO’s Very Large Telescope in Chile. An international team of astronomers has found that one of the stars [1] in NGC 3201 is behaving very oddly — it is being flung backwards and forwards at speeds of several hundred thousand kilometres per hour, with the pattern repeating every 167 days [2].

Lead author Benjamin Giesers (Georg-August-Universität Göttingen, Germany) was intrigued by the star’s behaviour: “It was orbiting something that was completely invisible, which had a mass more than four times the Sun — this could only be a black hole! The first one found in a globular cluster by directly observing its gravitational pull.”

The relationship between black holes and globular clusters is an important but mysterious one. Because of their large masses and great ages, these clusters are thought to have produced a large number of stellar-mass black holes — created as massive stars within them exploded and collapsed over the long lifetime of the cluster [3][4].

ESO’s MUSE instrument provides astronomers with a unique ability to measure the motions of thousands of far away stars at the same time. With this new finding, the team have for the first time been able to detect an inactive black hole at the heart of a globular cluster — one that is not currently swallowing matter and is not surrounded by a glowing disc of gas. They could estimate the black hole’s mass through the movements of a star caught up in its enormous gravitational pull [5].

From its observed properties the star was determined to be about 0.8 times the mass of our Sun, and the mass of its mysterious counterpart was calculated at around 4.36 times the Sun’s mass — almost certainly a black hole [6].

Recent detections of radio and X-ray sources in globular clusters, as well as the 2016 detection of gravitational-wave signals produced by the merging of two stellar-mass black holes, suggest that these relatively small black holes may be more common in globular clusters than previously thought.

Giesers concludes: “Until recently, it was assumed that almost all black holes would disappear from globular clusters after a short time and that systems like this should not even exist! But clearly this is not the case — our discovery is the first direct detection of the gravitational effects of a stellar-mass black hole in a globular cluster. This finding helps in understanding the formation of globular clusters and the evolution of black holes and binary systems — vital in the context of understanding gravitational wave sources.”

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Notes

[1] The star found is a main sequence turn-off star, meaning it is at the end of the main sequence phase of its life. Having exhausted its primary hydrogen fuel supply it is now on the way to becoming a red giant.

[2] A large survey of 25 globular clusters around the Milky Way is currently being conducted using ESO’s MUSE instrument with the support of the MUSE consortium. It will provide astronomers with the spectra of 600 to 27 000 stars in each cluster. The study includes analysis of the “radial velocity” of individual stars — the speed at which they move away from and toward the Earth, along the line of sight of the observer. With radial velocity measurements the orbits of stars can be determined, as well as the properties of any massive object they may be orbiting.

[3] In the absence of continuous star formation, as is the case for globular clusters, stellar-mass black holes soon become the most massive objects present. Generally, stellar-mass black holes in globular clusters are about four times as massive as the surrounding low-mass stars. Recent theories have concluded that black holes form a dense nucleus within the cluster, which then becomes detached from the rest of the globular material. Movements at the centre of the cluster are then thought to eject the majority of black holes, meaning only a few would survive after a billion years.

[4] Stellar-mass black holes — or collapsars — are formed when massive stars die, collapsing under their own gravity and exploding as powerful hypernovae. Left behind is a black hole with most of the mass of the former star, which can range from a few times the mass of our Sun to several tens of times as massive.

[5] As no light is able to escape black holes because of their tremendous gravity, the primary method of detecting them is through observations of radio or X-ray emissions coming from hot material around them. But when a black hole is not interacting with hot matter and so not accumulating mass or emitting radiation, as in this case, the black hole is “inactive” and invisible, so another method of detection is required.

[6] Because the non-luminous object in this binary system cannot be directly observed there are alternative, although much less persuasive, explanations for what it could be. It is perhaps a triple star system made up of two tightly bound neutron stars, with the observed star orbiting around them. This scenario would require each tightly bound star to be at least twice the mass of our Sun, a binary system that has never been observed before.

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More Information

This research was presented in a paper entitled “A detached stellar-mass black hole candidate in the globular cluster NGC 3201”, by B. Giesers et al., to appear in the journal Monthly Notices of the Royal Astronomical Society.

The team is composed of Benjamin Giesers (Georg-August-Universität Göttingen, Germany), Stefan Dreizler (Georg-August-Universität Göttingen, Germany), Tim-Oliver Husser (Georg-August-Universität Göttingen, Germany), Sebastian Kamann (Georg-August-Universität Göttingen, Germany; Liverpool John Moores University, Liverpool, United Kingdom), Guillem Anglada Escudé (Queen Mary University of London, United Kingdom), Jarle Brinchmann (Leiden Observatory, Leiden University, Leiden, The Netherlands; Universidade do Porto, CAUP, Porto, Portugal), C. Marcella Carollo (Swiss Federal Institute of Technology, ETH, Zurich, Switzerland) Martin M. Roth (Leibniz-Institut für Astrophysik Potsdam, Potsdam, Germany), Peter M. Weilbacher (Leibniz-Institut für Astrophysik Potsdam, Potsdam, Germany) and Lutz Wisotzki (Leibniz-Institut für Astrophysik Potsdam, Potsdam, Germany).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile and by Australia as a strategic partner. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its world-leading Very Large Telescope Interferometer as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. ESO is also a major partner in two facilities on Chajnantor, APEX and ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre Extremely Large Telescope, the ELT, which will become “the world’s biggest eye on the sky”.

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Links

• Research paper
• Information about the MUSE instrument on the VLT
• Photos of the VLT

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Contacts

Benjamin Giesers
Georg-August-Universität Göttingen
Göttigen, Germany
Email: giesers@astro.physik.uni-goettingen.de

Stefan Dreizler
Georg-August-Universität Göttingen
Göttigen, Germany
Email: dreizler@astro.physik.uni-goettingen.de

Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
Email: rhook@eso.org

 Source: ESO

NASA Space Telescopes Provide a 3D Journey Through the Orion Nebula

Visible and Infrared Visualization of the Orion Nebula

Credit: Image: NASA, ESA, F. Summers, G. Bacon, Z. Levay, J. DePasquale, L. Hustak, L. Frattare, M. Robberto and M. Gennaro (STScI), and R. Hurt (Caltech/IPAC).   Release Images - Release Videos

Astronomers and visualization specialists from NASA’s Universe of Learning program have combined visible and infrared vision of the Hubble and Spitzer space telescopes to create an unprecedented, three-dimensional, fly-through view of the picturesque Orion Nebula, a nearby star-forming region.

Viewers experience this nearby stellar nursery “close up and personally” as the new digital visualization ferries them among newborn stars, glowing clouds heated by intense radiation, and tadpole-shaped gaseous envelopes surrounding protoplanetary disks.

Using actual scientific imagery and other data, combined with Hollywood techniques, a team at the Space Telescope Science Institute in Baltimore, Maryland, and the Caltech/IPAC in Pasadena, California, has created the best and most detailed multi-wavelength visualization yet of this photogenic nebula. The fly-through enables people to experience and learn about the universe in an exciting new way.

The three-minute movie, which shows the Orion Nebula in both visible and infrared light, was released to the public today. It is available to planetariums and other centers of informal learning worldwide to help audiences explore fundamental questions in science such as, “How did we get here?”

“Being able to fly through the nebula’s tapestry in three dimensions gives people a much better sense of what the universe is really like,” explained the Space Telescope Science Institute’s visualization scientist Frank Summers, who led the team that developed the movie. “By adding depth and structure to the amazing images, this fly-through helps elucidate the universe for the public, both educating and inspiring,” added Summers.

“Looking at the universe in infrared light gives striking context for the more familiar visible-light views. This movie provides a uniquely immersive chance to see how new features appear as we shift to wavelengths of light normally invisible to our eyes,” said Robert Hurt, lead visualization scientist at IPAC.

One of the sky’s brightest nebulas, the Orion Nebula is visible to the naked eye. It appears as the middle “star” in the sword of the constellation Orion, the Hunter, and is located about 1,350 light-years away. At only 2 million years old, the nebula is an ideal laboratory for studying young stars and stars that are still forming. It offers a glimpse of what might have happened when the Sun was born 4.6 billion years ago.

The three-dimensional video provides a look at the fantastic topography of the nebula. A torrent of ultraviolet radiation and stellar winds from the massive, central stars of the Trapezium star cluster have carved out a cavernous bowl-like cavity in the wall of a giant cloud of cold molecular hydrogen laced with dust.

Astronomers and visualizers worked together to make a three-dimensional model of the depths of this cavernous region, like plotting mountains and valleys on the ocean floor. Colorful Hubble and Spitzer images were then overlaid on the terrain.

The scientific visualization video takes the viewer on a breathtaking flight through the nebula, following the contours of the gas and dust. By toggling between the Hubble and Spitzer’s views, the movie shows strikingly different details of the Orion Nebula.

Hubble sees objects that glow in visible light, which are typically in the thousands of degrees. Spitzer is sensitive to cooler objects with temperatures of just hundreds of degrees. Spitzer’s infrared vision pierces through obscuring dust to see stars embedded deep into the nebula, as well as fainter and less massive stars, which are brighter in the infrared than in visible light. The new visualization helps people experience how the two telescopes provide a more complex and complete picture of the nebula.

The visualization is one of a new generation of products and experiences being developed by the NASA’s Universe of Learning program. The effort combines a direct connection to the science and scientists of NASA’s Astrophysics missions with attention to audience needs to enable youth, families, and lifelong learners to explore fundamental questions in science, experience how science is done, and discover the universe for themselves.

The three-dimensional interpretation is guided by scientific knowledge and scientific intuition. Starting with the two-dimensional Hubble and Spitzer images, Summers and Hurt worked with experts to analyze the structure inside the nebula. They first created a visible-light surface, and then an underlying structure of the infrared features.

To give the nebula its ethereal feel, Summers wrote a special rendering code for efficiently combining the tens of millions of semi-transparent elements of the gas. The customized code allows Summers to run this and other visualizations on desktop workstations, rather than on a supercomputing cluster.

The other components of the nebula were isolated into image layers and modeled separately. These elements included stars, protoplanetary disks, bow shocks, and the thin gas in front of the nebula called “the veil.” After rendering, these layers and the gaseous nebula are brought back together to create the visualization.

The three-dimensional structures serve as scientifically reasonable approximations for imagining the nebula. “The main thing is to give the viewer an experiential understanding, so that they have a way to interpret the images from telescopes,” explained Summers. “It’s a really wonderful thing when they can build a mental model in their head to transform the two-dimensional image into a three-dimensional scene.”

This movie demonstrates the power of multi-wavelength astronomy. It helps audiences understand how science is done — how and why astronomers use multiple regions of the electromagnetic spectrum to explore and learn about our universe. It is also whetting astronomers’ appetites for what they will see with NASA’s James Webb Space Telescope, which will show much finer details of the deeper, infrared features.

More visualizations and connections between the science of nebulas and learners can be explored through other products produced by NASA’s Universe of Learning such as ViewSpace. ViewSpace is a video exhibit currently at almost 200 museums and planetariums across the United States. Visitors can go beyond video to explore the images produced by space telescopes with interactive tools now available for museums and planetariums.

NASA’s Universe of Learning materials are based upon work supported by NASA under award number NNX16AC65A to the Space Telescope Science Institute, working in partnership with Caltech/IPAC, Jet Propulsion Laboratory, Smithsonian Astrophysical Observatory, and Sonoma State University.

Source:  HubbleSite

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Related Links 

 
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• NASA’s Universe of Learning Portal
• NASA's Hubble Portal
• NASA's Spitzer Portal

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Contacts

Ann Jenkins / Ray Villard
Space Telescope Science Institute, Baltimore, Maryland
410-338-4488 / 410-338-4514
jenkins@stsci.edu / villard@stsci.edu

Elizabeth Landau
Jet Propulsion Laboratory, Pasadena, California
818-354-6425
Elizabeth.R.Landau@jpl.nasa.gov

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Game Over for Supernovae Hide & Seek

SN 2013if with GeMS/GSAOI, from left to right with linear scaling: Reference image (June 2015), discovery image (April 2013) and the image subtraction. SN 2013if had a projected distance from the nucleus as small as 600 light years (200 pc), which makes it the second most nuclear CCSN discovery in a LIRG to date in the optical and near-IR after SN 2010cu.

The Core-collapse Supernova Rate Problem, or the fact that we don’t see as many core-collapse supernovae as we would expect, has a solution, thanks to research using the Gemini South telescope. The research team concludes that the majority of core collapse supernovae, exploding in luminous infrared galaxies, have previously not been found due to dust obscuration and poor spatial resolution. 

Core-collapse supernovae are spectacular explosions that mark the violent deaths of massive stars. An international team of astronomers, led by PhD student Erik Kool of Macquarie University in Australia, used laser guide star imaging on the Gemini South telescope to study why we don’t see as many of these core-collapse supernovae as expected. The study began in 2015 with the Supernova UNmasked By InfraRed detection (SUNBIRD) project which has shown that dust obscuration and limited spatial resolution can explain the small number of detections to date.

In this, the first results of the SUNBIRD project, the team discovered three core-collapse supernovae, and one possible supernova that could not be confirmed with subsequent imaging. Remarkably, these supernovae were spotted as close as 600 light years from the bright nuclear regions of these galaxies – despite being at least 150 million light years from the Earth. “Because we observed in the near-infrared, the supernovae are less affected by dust extinction compared to optical light,” said Kool.

According to Kool the results coming from SUNBIRD reveal that their new approach provides a powerful tool for uncovering core-collapse supernova in nuclear regions of galaxies. They also conclude that this methodology is crucial in characterizing these supernova that are invisible through other means. Kool adds, “The supernova rate problem can be resolved using the unique multi-conjugate adaptive optics capability provided by Gemini, which allows us to achieve the highest spatial resolution in order to probe very close to the nuclear regions of galaxies.” This work is published in the Monthly Notices of the Royal Astronomical Society.

This research is also highlighted in the January 2018 GeminiFocus (p.11).

Source: Gemini Observatory

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Abstract: 

Core collapse supernova (CCSN) rates suffer from large uncertainties as many CCSNe exploding in regions of bright background emission and significant dust extinction remain unobserved. Such a shortfall is particularly prominent in luminous infrared galaxies (LIRGs), which have high star formation (and thus CCSN) rates and host bright and crowded nuclear regions, where large extinctions and reduced search detection efficiency likely lead to a significant fraction of CCSNe remaining undiscovered. We present the first results of project SUNBIRD (Supernovae UNmasked By InfraRed Detection), where we aim to uncover CCSNe that otherwise would remain hidden in the complex nuclear regions of LIRGs, and in this way improve the constraints on the fraction that is missed by optical seeing-limited surveys. We observe in the near-infrared 2.15 µm Ks-band, which is less affected by dust extinction compared to the optical, using the multi-conjugate adaptive optics imager GeMS/GSAOI on Gemini South, allowing us to achieve a spatial resolution that lets us probe close in to the nuclear regions. During our pilot program and subsequent first full year we have discovered three CCSNe and one candidate with projected nuclear offsets as small as 200 pc. When compared to the total sample of LIRG CCSNe discovered in the near-IR and optical, we show that our method is singularly effective in uncovering CCSNe in nuclear regions and we conclude that the majority of CCSNe exploding in LIRGs are not detected as a result of dust obscuration and poor spatial resolution.

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What Stars Will Hatch From The Tarantula Nebula? NASA’s Flying Observatory Seeks to Find Out

The Tarantula Nebula as seen on SOFIA’s visible light guide camera during observations from Christchurch, New Zealand.

Credits: NASA/SOFIA/Nicholas A. Veronico

To have a full picture of the lives of massive stars, researchers need to study them in all stages – from when they’re a mass of unformed gas and dust, to their often dynamic end-of-life explosions.

NASA's flying telescope, the Stratospheric Observatory for Infrared Astronomy, or SOFIA, is particularly well-suited for studying the pre-natal stage of stellar development in star-forming regions, such as the Tarantula Nebula, a giant mass of gas and dust located within the Large Magellanic Cloud, or LMC.  

Researchers from the Minnesota Institute for Astrophysics, led by Michael Gordon, went aboard SOFIA to identify and characterize the brightness, ages and dust content of three young star-forming regions within the LMC.

“The Large Magellanic Cloud has always been an interesting and excellent laboratory for massive star formation,” said Gordon. “The chemical properties of star-forming regions in the LMC are significantly different than in the Milky Way, which means the stars forming there potentially mirror the conditions of star formation in dwarf galaxies at earlier times in the universe.”

In our galactic neighborhood, which includes the LMC, massive stars – generally classified as stars more than eight times the mass of Earth’s Sun – are believed to form exclusively in very dense molecular clouds. The dark dust and gas absorb background light, which prevents traditional optical telescopes from imaging these areas.

“The mid-infrared capabilities of SOFIA are ideal for piercing through infrared dark clouds to capture images of potential massive star-forming regions,” Gordon said.

The observations were completed with the Faint Object infrared Camera for the SOFIA Telescope, known as FORCAST. This infrared camera also performs spectroscopy, which identifies the elements present.

Astronomers study stars evolving in both the optical and the infrared to learn more about the photosphere, and the population of stars in the photosphere. The mid- and far-infrared data from SOFIA reaffirm dust temperature and mass accretion rates that are consistent with prior research of the LMC.

"We want to combine as many observations as we can from the optical, as seen through images from the Hubble Space Telescope, all the way out to the far infrared, imaged using the Spitzer Space Telescope and the Herschel Space Observatory, to get as broad a picture as possible," Gordon continued. "No previous researchers have used FORCAST’s wavelength range to effectively study massive star formations. We needed SOFIA to fill in the 20- to 40-micron gap to give us the whole picture of what’s taking place."

In summer 2017, further research of the Tarantula Nebula was accomplished aboard SOFIA during the observatory’s six-week science campaign operating from Christchurch, New Zealand, to study the sky in the Southern Hemisphere. Gordon and his team are hopeful that when analyzed, data obtained from the Christchurch flights will reveal previously undiscovered young massive stars forming in the region, which have never been observed outside of the Milky Way.

SOFIA is a Boeing 747SP jetliner modified to carry a 100-inch diameter telescope. It is a joint project of NASA and the German Aerospace Center, DLR. NASA’s Ames Research Center in California’s Silicon Valley manages the SOFIA program, science and mission operations in cooperation with the Universities Space Research Association headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart. The aircraft is based at NASA’s Armstrong Flight Research Center's Hangar 703, in Palmdale, California.

Source: NASA/SOFIA

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Media Point of Contact

Nicholas A. Veronico
NVeronico@sofia.usra.edu • SOFIA Science Center
NASA Ames Research Center, Moffett Field, California

Editor: Kassandra Bell

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NASA's Great Observatories Team Up to Find Magnified and Stretched Image of Distant Galaxy

This Hubble Space Telescope image shows the farthest galaxy yet seen in an image that has been stretched and amplified by a phenomenon called gravitational lensing. Credits: NASA , ESA, and B. Salmon (STScI). › Full image and caption

An intensive survey deep into the universe by NASA's Hubble and Spitzer space telescopes has yielded the proverbial needle-in-a-haystack: the farthest galaxy yet seen in an image that has been stretched and amplified by a phenomenon called gravitational lensing.

The embryonic galaxy named SPT0615-JD existed when the universe was just 500 million years old.

Though a few other primitive galaxies have been seen at this early epoch, they have essentially all looked like red dots, given their small size and tremendous distances. However, in this case, the gravitational field of a massive foreground galaxy cluster not only amplified the light from the background galaxy but also smeared the image of it into an arc (about 2 arcseconds long).

"No other candidate galaxy has been found at such a great distance that also gives you the spatial information that this arc image does. By analyzing the effects of gravitational lensing on the image of this galaxy, we can determine its actual size and shape," said the study's lead author, Brett Salmon of the Space Telescope Science Institute in Baltimore. He is presenting his research at the 231st meeting of the American Astronomical Society in Washington.

First predicted by Albert Einstein a century ago, the warping of space by the gravity of a massive foreground object can brighten and distort the images of far more distant background objects. Astronomers use this "zoom lens" effect to go hunting for amplified images of distant galaxies that otherwise would not be visible with today's telescopes.

SPT0615-JD was identified in Hubble's Reionization Lensing Cluster Survey (RELICS) and companion S-RELICS Spitzer program. "RELICS was designed to discover distant galaxies like these that are magnified brightly enough for detailed study," said Dan Coe, principal investigator of RELICS. RELICS observed 41 massive galaxy clusters for the first time in infrared with Hubble to search for such distant lensed galaxies. One of these clusters was SPT-CL J0615-5746, which Salmon analyzed to make this discovery. Upon finding the lens-arc, Salmon thought, "Oh, wow! I think we're on to something!"

By combining the Hubble and Spitzer data, Salmon calculated the lookback time to the galaxy of 13.3 billion years. Preliminary analysis suggests the diminutive galaxy weighs in at no more than 3 billion solar masses (roughly 1/100th the mass of our fully grown Milky Way galaxy). It is less than 2,500 light-years across, half the size of the Small Magellanic Cloud, a satellite galaxy of our Milky Way. The object is considered prototypical of young galaxies that emerged during the epoch shortly after the big bang.

The galaxy is right at the limits of Hubble's detection capabilities, but just the beginning for the upcoming NASA James Webb Space Telescope's powerful capabilities, said Salmon. "This galaxy is an exciting target for science with the Webb telescope as it offers the unique opportunity for resolving stellar populations in the very early universe." Spectroscopy with Webb will allow for astronomers to study in detail the firestorm of starbirth activity taking place at this early epoch, and resolve its substructure.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington, D.C. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena. Spacecraft operations are based at Lockheed Martin Space, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at IPAC at Caltech. Caltech manages JPL for NASA.

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.

News Media Contact

Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278
guy.webster@jpl.nasa.gov

Ray Villard
Space Telescope Science Institute, Baltimore, Maryland
410-338-4514
villard@stsci.edu

Laurie Cantillo / Dwayne Brown
NASA Headquarters, Washington
202-358-1077 / 202-358-1726
laura.l.cantillo@nasa.gov / dwayne.c.brown@nasa.gov

Source: JPL-Caltech/News

No Planets Needed: NASA Study Shows Disk Patterns Can Self-Generate

Debris Disk Simulations Generate Spirals, Rings and Arcs

Arcs, rings and spirals appear in the debris disk around the star HD 141569A. The black region in the center is caused by a mask that blocks direct light from the star. This image incorporates observations made in June and August 2015 using the Hubble Space Telescope's STIS instrument. Credits: NASA/Hubble/Konishi et al. 2016 . Unlabeled version

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When exoplanet scientists first spotted patterns in disks of dust and gas around young stars, they thought newly formed planets might be the cause. But a recent NASA study cautions that there may be another explanation — one that doesn’t involve planets at all.

Exoplanet hunters watch stars for a few telltale signs that there might be planets in orbit, like changes in the color and brightness of the starlight. For young stars, which are often surrounded by disks of dust and gas, scientists look for patterns in the debris — such as rings, arcs and spirals — that might be caused by an orbiting world.

“We’re exploring what we think is the leading alternative contender to the planet hypothesis, which is that the dust and gas in the disk form the patterns when they get hit by ultraviolet light,” said Marc Kuchner, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

Kuchner presented the findings of the new study on Thursday, Jan. 11, at the American Astronomical Society meeting in Washington. A paper describing the results has been submitted to The Astrophysical Journal.

When high-energy UV starlight hits dust grains, it strips away electrons. Those electrons collide with and heat nearby gas. As the gas warms, its pressure increases and it traps more dust, which in turn heats more gas. The resulting cycle, called the photoelectric instability (PeI), can work in tandem with other forces to create some of the features astronomers have previously associated with planets in debris disks.

Kuchner and his colleagues designed computer simulations to better understand these effects. The research was led by Alexander Richert, a doctoral student at Penn State in University Park, Pennsylvania, and includes Wladimir Lyra, a professor of astronomy at California State University, Northridge and research associate at NASA’s Jet Propulstion Laboratory in Pasadena, California. The simulations were run on the Discover supercomputing cluster at the NASA Center for Climate Simulation at Goddard.

In 2013, Lyra and Kuchner suggested that PeI could explain the narrow rings seen in some disks. Their model also predicted that some disks would have arcs, or incomplete rings, which were first directly observed in 2016.

“People very often model these systems with planets, but if you want to know what a disk with a planet looks like, you first have to know what a disk looks like without a planet,” Richert said.

Richert is lead author on the new study, which builds on Lyra and Kuchner’s previous simulations by including an additional new factor: radiation pressure, a force caused by starlight striking dust grains.

Light exerts a minute physical force on everything it encounters. This radiation pressure propels solar sails and helps direct comet tails so they always point away from the Sun. The same force can push dust into highly eccentric orbits, and even blow some of the smaller grains out of the disk entirely.

The researchers modeled how radiation pressure and PeI work together to affect the movement of dust and gas. They also found that the two forces manifest different patterns depending on the physical properties of the dust and gas.

The 2013 simulations of PeI revealed how dust and gas interact to create rings and arcs, like those observed around the real star HD 141569A. With the inclusion of radiation pressure, the 2017 models show how these two factors can create spirals like those also observed around the same star. While planets can also cause these patterns, the new models show scientists should avoid jumping to conclusions.

“Carl Sagan used to say extraordinary claims require extraordinary evidence,” Lyra said. “I feel we are sometimes too quick to jump to the idea that the structures we see are caused by planets. That is what I consider an extraordinary claim. We need to rule out everything else before we claim that.”

Kuchner and his colleagues said they would continue to factor other parameters into their simulations, like turbulence and different types of dust and gas. They also intend to model how these factors might contribute to pattern formation around different types of stars.

A NASA-funded citizen science project spearheaded by Kuchner, called Disk Detective, aims to discover more stars with debris disks. So far, participants have contributed more than 2.5 million classifications of potential disks. The data has already helped break new ground in this research.

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By Jeanette Kazmierczak
NASA's Goddard Space Flight Center, Greenbelt, Md.

Editor: Rob Garner

Source:  NASA/Solar System and Beyond

A Quick Look at SDSS J1354+1327

 SDSS J1354+1327

Credit: X-ray NASA/CXC/University of Colorado/J. Comerford et al.; Optical: NASA/STScI

JPEG (165 kb) - Large JPEG (1.9 MB) - Tiff (106.8 MB) - More Images

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Using data from several telescopes including NASA's Chandra X-ray Observatory, astronomers have caught a supermassive black hole snacking on gas and then "burping" — not once but twice, as described in our latest press release.

This graphic shows the galaxy, called SDSS J1354+1327 (J1354 for short) in a composite image with data from Chandra (purple), and the Hubble Space Telescope (HST; red, green and blue). The inset box contains a close-up view of the central region around J1354's supermassive black hole. A companion galaxy to J1354 is shown to the north. Researchers also used data from the W.M. Keck Observatory atop Mauna Kea, Hawaii and the Apache Point Observatory (APO) in New Mexico for this finding.

Chandra detected a bright, point-like source of X-ray emission from J1354, a telltale sign of the presence of a supermassive black hole millions or billions of times more massive than our sun. The X-rays are produced by gas heated to millions of degrees by the enormous gravitational and magnetic forces near the black hole. Some of this gas will fall into the black hole, while a portion will be expelled in a powerful outflow of high-energy particles.

By comparing images from Chandra and HST, the team determined that the black hole is located in the center of the galaxy, the expected location for such an object. The X-ray data also provide evidence that the supermassive black hole is embedded in a heavy veil of dust and gas.

The two-course meal for the black hole comes from a companion galaxy that collided with J1354 in the past. This collision produced a stream of stars and gas that links J1354 and the other galaxy. The separate outbursts from the black hole are caused by different clumps from this stream being consumed by the supermassive black hole. The researchers determined these two "burps" happened about 100,000 years apart.

The team used optical data from HST, Keck and APO to show that electrons had been stripped from atoms in a cone of gas (the green emission in the lower left of the inset) extending some 30,000 light years south from the galaxy's center. This stripping was likely caused by a burst of radiation from the vicinity of the black hole, indicating that the first of the two feasting events had occurred. Evidence for the second, more recent feast comes from the small source of green emission located at the northern tip of the Chandra source in the inset.

Julie Comerford from the University of Colorado at Boulder presented the team's findings in a January 11th, 2018 press briefing at the 231st meeting of the American Astronomical Society held in Washington D.C. A paper on the subject was published in a recent issue of The Astrophysical Journal and is available online. Co-authors on the new study include postdoctoral fellows Rebecca Nevin, Scott Barrows and Francisco Muller-Sanchez of CU Boulder, Jenny Greene of Princeton University, David Pooley from Trinity University, Daniel Stern from the Jet Propulsion Laboratory in Pasadena, California, and Fiona Harrison from the California Institute of Technology.

NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.

A Quick Look at SDSS J1354+1327
Animation

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Fast Facts for SDSS J1354+1327:

Scale: Full field image: 37 arcsec (About 160,000 light years) across; Inset image: 3 arcsec (About 13,000 light years) across

Category: Quasars & Active Galaxies
Constellation: Boötes

Observation Date: June 25, 2014 

Observation Time 2 hours 37 minutes
Constellation: Boötes
Instrument: ACIS

Obs ID:  16115
References: J Comerford et al. 2017, ApJ, 849,102; arXiv:1710.00825
Distance Estimate: About 800 million light years (z=0.06)

Source: NASA’s Chandra X-ray Observatory