Lighting Up Andromeda’s Coldest Rings

Cold rings of dust are illuminated in this image taken by Herschel’s Spectral and Photometric Imaging Receiver (SPIRE) instrument. Credit: ESA/NASA/JPL-Caltech/B. Schulz (NHSC)

Looking wispy and delicate from 2.5 million light-years away, cold rings of dust are seen swirling around the Andromeda galaxy in this new image from the Herschel Space Observatory, giving us yet another fascinating view of our galaxy’s largest neighbor.

The colors in the image correspond to increasingly warmer temperatures and concentrations of dust — blue rings are warmer, while pinks and reds are colder lanes of dust only slightly above absolute zero. Dark at shorter wavelengths, these dust rings are revealed by Herschel’s amazing sensitivity to the coldest regions of the Universe.

The image above shows data only from Herschel’s SPIRE (Spectral and Photometric Imaging Receiver) instrument; below is a mosaic made from SPIRE as well as the Photodetecting Array Camera and Spectrometer (PACS) instrument:

In this new view of the Andromeda galaxy from the Herschel space observatory, cool lanes of forming stars are revealed in the finest detail yet.

 “Cool Andromeda” Credit: ESA/Herschel/PACS & SPIRE Consortium, O. Krause, HSC, H. Linz

Estimated to be 200,000 light-years across — almost double the width of the Milky Way — Andromeda (M31) is home to nearly a trillion stars, compared to the 200–400 billion that are in our galaxy. And within these cold, dark rings of dust even more stars are being born… Andromeda’s star-making days are far from over.

Read more: Star Birth and Death in the Andromeda Galaxy

Herschel’s mission will soon be coming to an end as the telescope runs out of the liquid helium coolant required to keep its temperatures low enough to detect such distant heat signatures. This is expected to occur sometime in February or March.

Herschel is a European Space Agency cornerstone mission with science instruments provided by consortia of European institutes, and with important participation by NASA. Launched May 14, 2009, the telescope orbits the second Lagrange point of the Earth-Sun system (L2), located 1.5 million km (932,000 miles) from Earth. Read more from the Herschel mission here.

So. Many. Stars…

Infrared image of globular cluster 47 Tucanae (NGC 104) captured by ESO’s VISTA telescope.

“My god, it’s full of stars!” said Dave Bowman in the movie 2010 as he entered the monolith, and one could imagine that the breathtaking view before him looked something like this.

Except this isn’t science fiction, it’s reality — this is an image of globular cluster 47 Tucanae taken by the European Southern Observatory’s VISTA telescope at the Paranal Observatory in Chile. It reveals in stunning detail a brilliant collection of literally millions of stars, orbiting our Milky Way galaxy at a distance of 15,000 light-years.

The full image can be seen below.

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47 Tucanae (also known as NGC 104) is located in the southern constellation Tucana. It’s bright enough to be seen without a telescope and, even though it’s very far away for a naked-eye object, covers an area about the size of the full Moon.

In reality the cluster is 124 light-years across.

Although globular clusters like 47 Tucanae are chock-full of stars — many of them very old, even as stars go — they are noticeably lacking in clouds of gas and dust. It’s thought that all the gaseous material has long since condensed to form stars, or else has been blown away by radiation and outbursts from the cluster’s exotic inhabitants.

At the heart of 47 Tucanae lie many curious objects like powerful x-ray sources, rapidly-spinning pulsars, “vampire” stars that feed on their neighbors, and strange blue stragglers — old stars that somehow manage to stay looking young. (You could say that a globular cluster is the cosmic version of a trashy reality show set in Beverly Hills.)

Red giants can be seen surrounding the central part of the cluster, old bloated stars that are running out of fuel, their outer layers expanding.

vista-survey-telescopeThe background stars in the image are part of the Small Magellanic Cloud, which was in the distance behind 47 Tucanae when this image was taken.

VISTA is the world’s largest telescope dedicated to mapping the sky in near-infrared wavelengths. Located at ESO’s Paranal Observatory in Chile, VISTA is revealing new views of the southern sky. Read more about the VISTA survey here.

Image credit: ESO/M.-R. Cioni/VISTA Magellanic Cloud survey. Acknowledgment: Cambridge Astronomical Survey Unit

Combining Light to Reveal Monster Black Holes

NGC 3627 glows in the combined light of Hubble, Chandra, Spitzer and the Very Large Telescope in this image. Astronomers conducted a survey of 62 galaxies, including NGC 3627 to study monster black holes at their centers.

It’s not just pretty, it’s science. Like a starry watercolor, astronomers combining light from Earth and space-based observatories found 37 new supermassive black hole candidates lurking in nearby galaxies.

Included in that survey is NGC 3627 pictured above. Astronomers combined X-ray data from NASA’s Chandra X-ray Observatory, infrared data from the Spitzer Space Telescope, and optical data from the Hubble Space Telescope and the Very Large Telescope. The other images give the galaxy context but it’s the ghostly blue images from Chandra that show super bright in the X-ray images; X-ray light powered by material falling into a monster black hole.

Gas and dust slowly spins around the black hole creating a flattened disk, or accretion disk. As material falls inward, it heats up and releases large amounts of energy that shine brightly in the ultraviolet region of the spectrum.

NGC 3627, located about 30 million light-years from Earth, was just one of a survey of 62 nearby galaxies using archived data from Chandra and data from the Spitzer Infrared Nearby Galaxy Survey. Of those, 37 galaxies contained bright X-ray sources, indicating active black holes at their cores. Scientists believe that seven of those sources are new supermassive black hole candidates.

The paper describing the survey results was published in the April 10, 2011 issue of The Astrophysical Journal.

Combining ultraviolet and infrared observations confirm previous Chandra results that found that there may be many more galaxies powered by monster black holes than believed previously through optical surveys. Scientists say in the paper that low-levels of black hole activity previously may have been hidden by dust or washed out by the bright light of the galaxy.

Image caption: Bright X-ray sources glow a ghostly blue in this image in NGC 3627 from NASA’s Chandra X-ray Observatory. A study confirms previous Chandra results that indicate that more galaxies powered by monster black holes populate the cosmos.

Source: Chandra X-ray Observatory website

The Brightest Galaxies in the Universe Were Invisible… Until Now

Hubble images of six of the starburst galaxies first found by ESA’s Herschel Space Observatory (Keck data shown below each in blue)

Many of the brightest, most actively star-forming galaxies in the Universe were actually undetectable by Earth-based observatories, hidden from view by thick clouds of opaque dust and gas. Thanks to ESA’s Herschel space observatory, which views the Universe in infrared, an enormous amount of these “starburst” galaxies have recently been uncovered, allowing astronomers to measure their distances with the twin telescopes of Hawaii’s W.M. Keck Observatory. What they found is quite surprising: at least 767 previously unknown galaxies, many of them generating new stars at incredible rates.

Although nearly invisible at optical wavelengths these newly-found galaxies shine brightly in far-infrared, making them visible to Herschel, which can peer through even the densest dust clouds. Once astronomers knew where the galaxies are located, they were able to target them with Hubble and, most importantly, the two 10-meter Keck telescopes — the two largest optical telescopes in the world.

By gathering literally hundreds of hours of spectral data on the galaxies with the Keck telescopes, estimates of their distances could be determined as well as their temperatures and how often new stars are born within them.

“While some of the galaxies are nearby, most are very distant; we even found galaxies that are so far that their light has taken 12 billion years to travel here, so we are seeing them when the Universe was only a ninth of its current age,” said Dr. Caitlin Casey, Hubble fellow at the UH Manoa Institute for Astronomy and lead scientist on the survey. “Now that we have a pretty good idea of how important this type of galaxy is in forming huge numbers of stars in the Universe, the next step is to figure out why and how they formed.”

A representation of the distribution of nearly 300 starbursts in one 1.4 x 1.4 degree field of view.

The galaxies, many of them observed as they were during the early stages of their formation, are producing new stars at a rate of 100 to 500 a year — with a mass equivalent of several thousand Suns — hence the moniker “starburst” galaxy. By comparison the Milky Way galaxy only births one or two Sun-mass stars per year.

The reason behind this explosion of star formation in these galaxies is unknown, but it’s thought that collisions between young galaxies may be the cause.

Another possibility is that galaxies had much more gas and dust during the early Universe, allowing for much higher star formation rates than what’s seen today.

“It’s a hotly debated topic that requires details on the shape and rotation of the galaxies before it can be resolved,” said Dr. Casey.

Still, the discovery of these “hidden” galaxies is a major step forward in understanding the evolution of star formation in the Universe.

“Our study confirms the importance of starburst galaxies in the cosmic history of star formation. Models that try to reproduce the formation and evolution of galaxies will have to take these results into account.”

– Dr. Caitlin Casey, Hubble fellow at the UH Manoa Institute for Astronomy

“For the first time, we have been able to measure distances, star formation rates, and temperatures for a brand new set of 767 previously unidentified galaxies,” said Dr. Scott Chapman, a co-author on the studies. “The previous similar survey of distant infrared starbursts only covered 73 galaxies. This is a huge improvement.”

The papers detailing the results were published today online in the Astrophysical Journal.

Sources: W.M. Keck Observatory article and ESA’s news release.

Image credits: ESA–C. Carreau/C. Casey (University of Hawai’i); COSMOS field: ESA/Herschel/SPIRE/HerMES Key Programme; Hubble images: NASA, ESA. Inset image courtesy W. M. Keck Observatory.

Here There Be Planets: Stellar Disk Gap May Reveal Newborn Worlds

HiCIAO near-infrared image of the protoplanetary disk around PDS 70. The circular mask hides the star itself, as well as a smaller internal disk structure. (Credit: NAOJ)

Over the past couple of decades astronomers have figured out several methods for finding planets around other stars in our galaxy. Some have revealed their presence by the slight “wobble” they impart to their host stars as they orbit, while others have been discovered as they pass in front of their stars from our perspective, briefly dimming the light we see.

Now, some astronomers think they may have identified the presence of multiple planets, based on a large gap found in the disk of  gas and dust surrounding a Sun-like star 460 light-years from Earth.

Using the High Contrast Instrument for the Subaru Next Generation Adaptive Optics (HiCIAO) mounted on Japan’s 8.2-meter optical-infrared Subaru telescope atop Mauna Kea in Hawaii, an international team of astronomers targeted PDS 70, a young star (10 million years old) about the same mass as the Sun located 460 light-years away in the constellation Centaurus.

The near-infrared observations made by HiCIAO reveal a protoplanetary disk surrounding PDS 70. This disk is composed of gas and dust and extends billions of miles out from the star. Quite literally the stuff that planets are made of, it’s a disk much like this that our solar system likely started out as over 4.6 billion years ago.

“Thanks to the powerful combination of the Subaru Telescope and HiCIAO, we are able to probe the disks around Sun-like stars. PDS 70 shows how our solar system may have looked in its infancy. I want to continue this kind of research to understand the history of planetary formation.”

– Team Leader Jun Hashimoto (NAOJ)

Within PDS 70’s disk are several large gaps positioned at varying distances from the star itself, appearing as dark regions in the near-infrared data. These gaps — especially the largest, located about 70 AU from the star — are thought to be the result of newly-formed planets having cleared the surrounding space of dust and smaller material. It’s also believed that multiple planets may be present since, according to the team, “no single planet, regardless of how heavy or efficient it is in its formation, is sufficient to create such a giant gap.”

In addition to the large disk structure and outer gap, PDS 70 also has a smaller disk located only 1 AU away. (This disk is obscured by the HiCIAO mask in the image above.)

Further observations will be needed to locate any actual exoplanets directly, since the light from the star and scattered light within the disk makes it difficult — if not impossible with current technology — to detect the incredibly faint light reflected by planets.

Still, it’s fascinating to come across what may very well be a solar system in its infancy, giving us a glimpse back in time to our own formation.

“Direct imaging of planets in the process of forming in protoplanetary disks would be ideal so that we can learn when, where, and how planets form,” said team leader Ruobing Dong of Princeton University.

Read more on the NAOJ website for the Subaru Observatory here.

The goal of the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) Project is to study the disks around less massive stars like the Sun.

Inset image: Artist’s rendition of PDS 70 and its two protoplanetary disks (NAOJ)

Monster Black Holes Lurk at the Edge of Time

The reddish object in this infrared image is ULASJ1234+0907, located about 11 billion light-years from Earth. The red color comes from vast amounts of dust, which absorbs bluer light, and obscures the supermassive black hole from view in visible wavelengths. Credit: image created using data from UKIDSS and the Wide-field Infrared Survey Explorer (WISE) observatory.

As if staring toward the edge of the Universe weren’t fascinating enough, scientists at the University of Cambridge say they see enormous, rapidly growing supermassive black holes barely detectable near the edge of time.

Thick dust shrouds the monster black holes but they emit vast amounts of radiation through violent interactions and collisions with their host galaxies making them visible in the infrared part of the electromagnetic spectrum. The team published their results in the journal Monthly Notices of the Royal Astronomical Society.

The most remote object in the study lies at a whopping 11 billion light-years from Earth. Ancient light from the supermassive black hole, named ULASJ1234+0907 and located toward the constellation of Virgo, the Maiden, has traveled (at almost 10 trillion kilometers, or 6 million million miles, per year) across the cosmos for nearly the estimated age of the Universe. The monster black hole is more than 10 billion times the mass of our Sun and 10,000 times more massive than the black hole embedded in the Milky Way Galaxy; making it one of the most massive black holes ever seen. And it’s not alone. Researchers say that there may be as many as 400 giants black holes in the tiny sliver of the Universe that we can observe.

“These results could have a significant impact on studies of supermassive black holes” said Dr Manda Banerji, lead author of the paper, in a press release. “Most black holes of this kind are seen through the matter they drag in. As the neighbouring material spirals in towards the black holes, it heats up. Astronomers are able to see this radiation and observe these systems.”

The team from Cambridge used infrared surveys being carried out on the UK Infrared Telescope (UKIRT) to peer through the dust and locate the giant black holes for the first time.

“These results are particularly exciting because they show that our new infrared surveys are finding super massive black holes that are invisible in optical surveys,” says Richard McMahon, co-author of the study. “These new quasars are important because we may be catching them as they are being fed through collisions with other galaxies. Observations with the new Atacama Large Millimeter Array (ALMA) telescope in Chile will allow us to directly test this picture by detecting the microwave frequency radiation emitted by the vast amounts of gas in the colliding galaxies.”

Huge black holes are known to reside at the centers of all galaxies. Astronomers predict the most massive of these cosmic phenomena grow through violent collisions with other galaxies. Galactic interactions trigger star formation which provides more fuel for black holes to devour. And it’s during this process that thick layers of dust hide the munching black holes.

“Although these black holes have been studied for some time,” says Banergi, “the new results indicate that some of the most massive ones may have so far been hidden from our view. The newly discovered black holes, devouring the equivalent of several hundred Suns every year, will shed light on the physical processes governing the growth of all supermassive black holes.”

Astronomers compare the extreme case of ULASJ1234+0907 with the relatively nearby and well-studied Markarian 231. Markarian 231, found just 600 million light-years away, appears to have recently undergone a violent collision with another galaxy producing an example of a dusty, growing black hole in the local Universe. By contrast, the more extreme example of ULASJ1234+0907, shows scientists that conditions in the early Universe were more turbulent and inhospitable than today.

Source: Royal Astronomical Society

Image Credit: Markarian 231, an example of a galaxy with a dusty rapidly growing supermassive black hole located 600 million light years from Earth. The bright source at the center of the galaxy marks the black hole while rings of gas and dust can be seen around it as well as “tidal tails” left over from a recent impact with another galaxy. Courtesy of NASA/ESA Hubble Space Telescope.

Blowing a Super-duper Celestial Bubble

Image credit: X-ray: NASA/CXC/U.Mich./S.Oey, IR: NASA/JPL, Optical: ESO/WFI/2.2-m. Zoom by John Williams/TerraZoom using Zoomify

When NASA combines images from different telescopes, they create dazzling scenes of celestial wonder and in the process we learn a few more things. Behold this wonder of combined light, known as LHA 120-N 44, or N 44 for short. Zoom into the scene using the toolbar at the bottom of the image. Click the farthest button on the right of the toolbar to see this wonder in full-screen. (Hint: press the “Esc” key to get back to work)

Continue reading “Blowing a Super-duper Celestial Bubble”

Canada Unveils its Contributions to the JWST

Today Canada’s Minister of Industry Christian Paradis unveiled the technologies that comprise Canada’s contribution to the James Webb Space Telescope, a next-generation infrared observatory that’s seen as the successor to Hubble.


CSA will provide JWST with a two-in-one instrument: a Fine Guidance Sensor (FGS) Near-Infrared Imager and Slitless Spectrograph (NIRISS). Both were designed, built and tested by COM DEV International in Ottawa and Cambridge, Ontario, with technical contributions from the Université de Montréal and the National Research Council Canada.

Read: Watch the James Webb Being Built via “Webb-Cam”

“Canada has a proud legacy in space and we are once again pushing the frontier of what is possible. These two outstanding technologies are perfect examples of how Canada has secured its world-class reputation. Our Government is committed to ensuring the long-term competitiveness and prosperity of such a vital economic sector.”
– The Honourable Christian Paradis

The FGS consists of two identical cameras that are critical to Webb’s ability to “see.” Their images will allow the telescope to determine its position, locate its celestial targets, and remain pointed to collect high-quality data. The FGS will guide the telescope with incredible precision, with an accuracy of one millionth of a degree.

The NIRISS will have unique capabilities for finding the earliest and most distant objects in the Universe’s history. It will also peer through the glare of nearby young stars to unveil new Jupiter-like exoplanets. It will have the capability of detecting the thin atmosphere of small, habitable, earth-like planets and determine its chemical composition to seek water vapour, carbon dioxide and other potential biomarkers such as methane and oxygen.

The FGS/NIRISS instruments can be seen in this development video from CSA:

“Imagine the challenge at hand here: to design and deliver technology capable of unprecedented levels of precision to conduct breakthrough science on board the largest, most complex and most powerful telescope ever built,” said Steve MacLean, President of the CSA. “The Webb telescope will be located 1.5 million kilometers from Earth— too far to be serviced by astronauts like Hubble was. At that distance, the technology simply has to work. This is the outstanding level of excellence Canadians are capable of achieving. It’s something for all of us to be proud of.”

The instruments will be delivered to NASA on July 30.

Read more on the CSA press release here, and learn more about the James Webb here.

Images/video: CSA and NASA

The Case of the Disappearing Dust

Astronomy has always taught us that planets form from vast clouds of dust and gas orbiting young stars. It’s a gradual process of accretion that takes hundreds of thousands, perhaps even millions, of years… or does it?

During a 1983 sky survey with the Infrared Astronomical Satellite (IRAS) astronomers identified a young Sun-like star with a large cloud of dust surrounding it. The star, named TYC 8241 2652 1, is 450 light years away and what they had found around it was thought to be the beginnings of a solar system – the protoplanetary disc from which planets form.

Fast forward to 2008. Astronomers observed at the same star with a different infrared telescope, the Gemini South Observatory in Chile. What was observed looked a lot like what was previously seen in ’83.

Then, in 2009, they looked again. Curiously, the brightness of the dust cloud was only a third of what it was the year before. And in WISE observations made the very next year, it had disappeared entirely.

“It’s like the classic magician’s trick: now you see it, now you don’t. Only in this case we’re talking about enough dust to fill an inner solar system, and it really is gone.”

– Carl Melis, lead author and postdoctoral fellow at UC San Diego

Abracadabra?

“It’s as if you took a conventional picture of the planet Saturn today and then came back two years later and found that its rings had disappeared,” said study co-author and circumstellar disk expert Ben Zuckerman of UCLA.

It’s always been thought that planets take some time to form, in the order of hundreds of thousands of years. Although that may seem like forever to humans, it’s quick in cosmic time scales. But if what they’ve seen here with TYC 8241 is in fact planetary formation, well… it may happen a lot faster than anyone thought.

On the other hand, the star could have somehow blown all the dust out of the system. More research will be needed to see if that was the case.

The really interesting thing here is that astronomers have traditionally looked for these kinds of dust clouds around stars to spot planetary formation in action. But if planets form quicker than we thought, and the dust clouds are only fleeting features, then there may be a lot more solar systems out there that we can’t directly observe.

“People often calculate the percentage of stars that have a large amount of dust to get a reasonable estimate of the percentage of stars with planetary systems, but if the dust avalanche model is correct, we cannot do that anymore,” said study co-author Inseok Song, assistant professor of physics and astronomy at the University of Georgia. “Many stars without any detectable dust may have mature planetary systems that are simply undetectable.”

Read more in the news release from the University of Georgia.

Top image: Gemini Observatory/AURA artwork by Lynette Cook.

WISE Spies a Hunter’s Flame

A vast star-forming cloud of gas and dust in the constellation Orion shines brightly in this image from NASA’s WISE space telescope, where infrared light is represented in visible wavelengths. It’s part of a recent data release from WISE, a trove of infrared images acquired during the telescope’s second sky scan from August to September of 2010 — just as it began to run out of its essential cryogenic coolant.

Shining brightly in infrared radiation, the Flame nebula (NGC 2024) is at the heart of the cloud.  Just below it is the reflection nebula NGC 2023, and the small, bright loop protruding from the edge of the gas and dust cloud just to its lower right is the Horsehead nebula  — whose famous equine profile appears quite different in infrared light than it does in visible.

The two bright blue stars at the upper right portion of the image are both stars in Orion’s belt. Alnitak, the brighter one closer to the Flame nebula, is a multiple star system located 736 light-years away whose stellar wind is responsible for ionizing the Flame nebula and causing it to shine in infrared. Alnilam, the dimmer star at the uppermost corner, is a blue supergiant 24 times the radius of our Sun and 275,000 times as bright, but 1,980 light-years distant.

The red arc at lower right is the bow shock of Sigma Orionis, a multiple-star system that’s hurtling through space at a speed of 5,260,000 mph (2,400 kilometers per second). As its stellar wind impacts the interstellar medium and piles up before it, an arc of infrared-bright radiation is emitted.

Sigma Orionis is also the star responsible for the glow of the Horsehead nebula.

This rich astronomical scene is an expanded view from WISE’s previously-released image of the region (at right) which used data from only three of its four infrared detectors. In contrast, all four detectors were used in the image above, making more of the nebulae’s intricate structures visible as well as providing comparative information for researchers.

“If you’re an astronomer, then you’ll probably be in hog heaven when it comes to infrared data,” said Edward (Ned) Wright of UCLA, the principal investigator of the WISE mission. “Data from the second sky scan are useful for studying stars that vary or move over time, and for improving and checking data from the first scan.”

Read more on the NASA news release here.

Top and right images: NASA/JPL-Caltech/WISE team. Horsehead nebula visible light image was taken with the 0.9-meter telescope at Kitt Peak National Observatory. Photo credit & copyright: Nigel Sharp (NOAO), KPNO, AURA, NSF. Comparison by J. Major/Universe Today.