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.”
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.”
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.
An international team of astronomers has figured out a way to determine details of an exoplanet’s atmosphere from 50 light-years away… even though the planet doesn’t transit the face of its star as seen from Earth.
Tau Boötis b is a “hot Jupiter” type of exoplanet, 6 times more massive than Jupiter. It was the first planet to be identified orbiting its parent star, Tau Boötis, located 50 light-years away. It’s also one of the first exoplanets we’ve known about, discovered in 1996 via the radial velocity method — that is, Tau Boötis b exerts a slight tug on its star, shifting its position enough to be detectable from Earth. But the exoplanet doesn’t pass in front of its star like some others do, which until now made measurements of its atmosphere impossible.
Today, an international team of scientists working with the Very Large Telescope (VLT) at ESO’s Paranal Observatory in Chile have announced the success of a “clever new trick” of examining such non-transiting exoplanet atmospheres. By gathering high-quality infrared observations of the Tau Boötis system with the VLT’s CRIRES instrument the researchers were able to differentiate the radiation coming from the planet versus that emitted by its star, allowing the velocity and mass of Tau Boötis b to be determined.
“Thanks to the high quality observations provided by the VLT and CRIRES we were able to study the spectrum of the system in much more detail than has been possible before,” said Ignas Snellen with Leiden Observatory in the Netherlands, co-author of the research paper. “Only about 0.01% of the light we see comes from the planet, and the rest from the star, so this was not easy.”
Using this technique, the researchers determined that Tau Boötis b’s thick atmosphere contains carbon monoxide and, curiously, exhibits cooler temperatures at higher altitudes — the opposite of what’s been found on other hot Jupiter exoplanets.
“Maybe one day we may even find evidence for biological activity on Earth-like planets in this way.”
– Ignas Snellen, Leiden Observatory, the Netherlands
In addition to atmospheric details, the team was also able to use the new method to determine Tau Boötis b’s mass and orbital angle — 44 degrees, another detail not previously identifiable.
“The new technique also means that we can now study the atmospheres of exoplanets that don’t transit their stars, as well as measuring their masses accurately, which was impossible before,” said Snellen. “This is a big step forward.
“Maybe one day we may even find evidence for biological activity on Earth-like planets in this way.”
This research was presented in a paper “The signature of orbital motion from the dayside of the planet Tau Boötis b”, to appear in the journal Nature on June 28, 2012.
Added 6/27: The team’s paper can be found on arXiv here.
Top image: artist’s impression of the exoplanet Tau Boötis b. (ESO/L. Calçada). Side image: ESO’s VLT telescopes at the Paranal Observatory in Chile’s Atacama desert. (Iztok Boncina/ESO)
Artist's impression of the European Extremely Large Telescope. Credit: ESO
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The world’s largest optical/infrared telescope has been given the initial go-ahead to be built. Called the European Extremely Large Telescope (E-ELT) this long-proposed new ground-based telescope will have a 40-meter main mirror and observe the universe in visible and infrared light, making direct images of exoplanets, perhaps find Earth-sized and even Earth-like worlds, and study the first galaxies that formed after the Big Bang.
“This is an excellent outcome and a great day for ESO. We can now move forward on schedule with this giant project,” said the ESO Director General, Tim de Zeeuw.
At a meeting in Garching, France this week, the ESO (European Southern Observatory) Council approved the E-ELT program, with 6 out of 10 countries giving firm approval and four gave “ad referendum” approval, meaning that they needed an official green light from their governments. With that approval, officials are hopeful the E-ELT could start operations by the early 2020’s.
The new super-large eye on the sky will be built at Cerro Armazones in northern Chile, close to ESO’s Paranal Observatory.
The cost is expected to be $1.35 billion USD (1.083-billion-euro)
“World-leading projects of this kind inspire us all and are hugely effective in bringing young people into careers in science and technology,” said David Southwood, president of the Royal Astronomical Society.
This type of telescope has been on the priority list for astronomy by scientists around the world.
The E-ELT will gather 100 million times more light than the human eye, eight million times more than Galileo’s telescope which saw the four biggest moons of Jupiter four centuries ago, and 26 times more than a single VLT telescope.
“The E-ELT will tackle the biggest scientific challenges of our time, and aim for a number of notable firsts, including tracking down Earth-like planets around other stars in the ‘habitable zones’ where life could exist — one of the Holy Grails of modern observational astronomy,” the ESO said.
ESO said that early contracts for the project have already been placed. Shortly before the Council meeting, a contract was signed to begin a detailed design study for the very challenging M4 adaptive mirror of the telescope. This is one of the longest lead-time items in the whole E-ELT program, and an early start was essential.
Detailed design work for the route of the road to the summit of Cerro Armazones, where the E-ELT will be sited, is also in progress and some of the civil works are expected to begin this year. These include preparation of the access road to the summit of Cerro Armazones as well as the leveling of the summit itself.
This new view of the Cygnus-X star-formation region by Herschel highlights chaotic networks of dust and gas that point to sites of massive star formation. Credits: ESA/PACS/SPIRE/Martin Hennemann & Frédérique Motte, Laboratoire AIM Paris-Saclay, CEA/Irfu – CNRS/INSU – Univ. Paris Diderot, France.
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In infrared, Cygnus-X is a glowing star nursery, and the Herschel space observatory has captured this beautiful new view showing an extremely active region of big-baby stars. It is located about 4,500 light-years from Earth in the constellation of Cygnus, the Swan. The image highlights the unique capabilities of Herschel to probe the birth of large stars and their influence on the surrounding interstellar material.
The bright white areas are where large stars have recently formed out of turbulent clouds, especially evident in the chaotic network of filaments seen in the right-hand portion of the image. The dense knots of gas and dust collapse to form new stars; the bubble-like structures are carved by the enormous radiation emitted by these stars.
In the center of the image, fierce radiation and powerful stellar winds from stars undetected at Herschel’s wavelengths have partly cleared and heated interstellar material, which then glows blue. The threads of compact red objects scattered throughout the image shows where future generations of stars will be born.
The side of the SOFIA aircraft shows it's joint roots, a collaboration between NASA and German Scientists. Credit: Nick Howes
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One of the most remarkable observatories in the world does its work not on a mountaintop, not in space, but 45,000 feet high on a Boeing 747. Nick Howes took a look around this unique airliner as it made its first landing in Europe.
SOFIA (Stratospheric Observatory for Infrared Astronomy) came from an idea first mooted in the mid-1980s. Imagine, said scientists, using a Boeing 747 to carry a large telescope into the stratosphere where absorption of infrared light by atmospheric water molecules is dramatically reduced, even in comparison with the highest ground-based observatories. By 1996 that idea had taken a step closer to reality when the SOFIA project was formally agreed between NASA (who fund 80 percent of the cost of the 330 million dollar mission, an amount comparable to a single modest space mission) and the German Aerospace Centre (DLR, who fund the other 20 percent). Research and development began in earnest using a highly modified Boeing 747SP named the ‘Clipper Lindburgh’ after the famous American pilot, and where the ‘SP’ stands for ‘Special Performance’.
Maiden test flights were flown in 2007, with SOFIA operating out of NASA’s Dryden Flight Research Center at Edwards Airforce Base in the Rogers Dry Lake in California – a nice, dry location that helps with the instrumentation and aircraft operationally.
This scale model shows the telescope position and how the aircraft design works around it. Credit: Nick Howes.
As the plane paid a visit to the European Space Agency’s astronaut training centre in Cologne, Germany, I was given a rare opportunity to look around this magnificent aircraft as part of a European Space ‘Tweetup’ (a Twitter meeting). What was immediately noticeable was the plane’s shorter length to the ones you usually fly on, which enables the aircraft to stay in the air for longer, a crucial aspect for its most important passenger, the 2.7-metre SOFIA telescope. Its Hubble Space Telescope-sized primary mirror is aluminium coated and bounces light to a 0.4-metre secondary, all in an open cage framework that literally pokes out of the side of the aircraft.
As we have seen, the rationale for placing a multi-tonne telescope on an aircraft is that by doing so it is possible to escape most of the absorption effects of our atmosphere. Observations in infrared are largely impossible for ground-based instruments at or near sea-level and only partially possibly even on high mountaintops. Water vapour in our troposphere (the lower layer of the atmosphere) absorbs so much of the infrared light that traditionally the only way to beat this was to send up a spacecraft. SOFIA can fill a niche by doing nearly the same job but at far less risk and with a far longer life-span. The aircraft has sophisticated infrared monitoring cameras to check its own output,and water vapour monitoring to measure what little absorption is occurring.
The Sofia Telescope resides behind the multi tonne frame and control mechanism. Credit: Nick Howes.
The 2.7-metre mirror (although actually only 2.5-metres is really used in practice,) uses a glass ceramic composite that is highly thermally tolerant, which is vital given the harsh conditions that the aircraft puts the isolated telescope through. If one imagines the difficulty amateur astronomers have some nights with telescope stability in blustery conditions, spare a thought for SOFIA, whose huge f/19.9 Cassegrain reflecting telescope has to deal with an open door to the
800 kilometres per hour (500 miles per hour) winds .Nominally some operations will occur at 39,000 feet (approximately 11,880 metres) rather than the possible ceiling of 45,000 feet (13,700 metres), because while the higher altitude provides slightly better conditions in terms of lack of absorption (still above 99 percent of the water vapour that causes most of the problems), the extra fuel needed means that observation times are reduced significantly, making the 39,000
feet altitude operationally better in some instances to collect more data. The aircraft uses a cleverly designed air intake system to funnel and channel the airflow and turbulence away from the open telescope window, and speaking to the pilots and scientists, they all agreed that there was no effect caused by any output from the aircraft engines as well.
Staying cool
The cameras and electronics on all infrared observatories have to be maintained at very low temperatures to avoid thermal noise from them spilling into the image, but SOFIA has an ace up its sleeve. Unlike a space mission (with the exception of the servicing missions to the Hubble Space Telescope that each cost $1.5 billion including the price of launching a space shuttle), SOFIA has the advantage of being able to replace or repair instruments or replenish its coolant, allowing an estimated life-span of at least 20 years, far longer than any space-based infrared mission that runs out of coolant after a few years.
Meanwhile the telescope and its cradle are a feat of engineering. The telescope is pretty much fixed in azimuth, with only a three-degree play to compensate for the aircraft, but it doesn’t need to move in that direction as the aircraft, piloted by some of NASA’s finest, performs that duty for it. It can work between a 20–60 degree altitude range during science operations. It’s all been engineered to tolerances that make the jaw drop. The bearing sphere, for example, is polished to an accuracy of less than ten microns, and the laser gyros provide angular increments of 0.0008 arcseconds. Isolated from the main aircraft by a series of pressurised rubber bumpers, which are altitude compensated, the telescope is almost completely free from the main bulk of the 747, which houses the computers and racks that not only operate the telescope but provide the base station for any observational scientists flying with the plane.
PI in the Sky
The science principle investigators get to sit in relative comfort close to the telescope. Credit: Nick Howes.
The Principle Investigator station is located around the mid-point of the aircraft, several metres from the telescope but enclosed within the plane (exposed to the air at 45,000 feet, the crew and scientists would otherwise be instantly killed). Here, for ten or more hours at a time, scientists can gather data once the door opens and the telescope is pointing at the target of choice, with the pilots following a precise flight path to maintain both the instrument pointing accuracy and also to best avoid the possibility of turbulence. Whilst ground-based telescopes can respond quickly to events such as a new supernova, SOFIA is more regimented in its science operations and, with proposal cycles over six months to a year, one has to plan quite accurately how best to observe an object.
Forecasting the future
Science operations started in 2010 with FORCAST (Faint Object Infrared Camera for Sofia Telescope) and continued into 2011 with the GREAT (German Receiver for Astronomy at Teraherz Frequencies) instrument. FORCAST is a mid/far infrared instrument working with two cameras between at five and forty microns (in tandem they can work between 10–25 microns) with a 3.2 arcminute field-of-view. It saw first light on Jupiter and the galaxy Messier 82, but will be working on imaging the galactic centre, star formation in spiral and active galaxies and also looking at molecular clouds, one of its primary science goals enabling scientists to accurately determine dust temperatures and more detail on the morphology of star forming regions down to less than three-arcsecond resolution (depending on the wavelength the instrument works at). Alongside this, FORCAST is also able to perform grism (i.e. a grating prism) spectroscopy, to get more detailed information on the composition of objects under view. There is no adaptive optics system, but it doesn’t need one for the types of operations it’s doing.
FORCAST and GREAT are just two of the ‘basic’ science operation instruments, which also include Echelle spectrographs, far infrared spectrometers and high resolution wideband cameras, but already the science team are working on new instruments for the next phase of operations. Instrumentation switch over, whilst complex, is relatively quick (comparable to the time it takes to switch instruments on larger ground observatories), and can be achieved in readiness for observations, which the plane aims to do up to 160 times per year. And whilst there were no firm plans to build a sister ship for SOFIA, there have been discussions among scientists to put a larger telescope on an Airbus A380.
A model of the telescope shows its unique control and movement mechanism as well as the optical tube assembly. Credit: Nick Howes.
Sky Outreach
With a planned science ambassador programme involving teachers flying on the aircraft to do research, SOFIA’s public profile is going to grow. The science output and possibilities from instruments that are constantly evolving, serviceable and improvable every time it lands is immeasurable in comparison to space missions. Journalists had only recently been afforded the opportunity to visit this remarkable aircraft, and it was a privilege and honour to be one of the first people to see it up close. To that end I wish to thank ESA and NASA for the invitation and chance to see something so unique.
Infrared imaging of the Sombrero Galaxy (M104) reveals both elliptical and disk structures.
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The Sombrero galaxy has a split personalty, according to recent observations by NASA’s Spitzer Space Telescope. Infrared imaging has revealed a hazy elliptical halo of stars enveloping a dual-structured inner disk; before this, the Sombrero galaxy was thought to be only disk-shaped.
Spitzer’s heat-seeking abilities reveal both stars and dust within the Sombrero galaxy, also known as Messier 104 and NGC 4594. The starlight detected at 3.5 and 4.6 microns is represented in blue-green while the dust imaged at 8.0 microns is shown in red.
In addition, Spitzer discerned that the flat disk within the galaxy is made up of two sections — an inner disk composed almost entirely of stars with no dust, and an outer ring containing both dust and stars.
The galaxy’s dual personality couldn’t be so clearly seen in previous visible-light images.
Hubble image of M104. (NASA/The Hubble Heritage Team STScl/AURA)
“The Sombrero is more complex than previously thought,” said Dimitri Gadotti of the European Southern Observatory in Chile and lead author of the report. “The only way to understand all we know about this galaxy is to think of it as two galaxies, one inside the other.”
Although it might seem that the Sombrero is the result of a collision between two separate galaxies, that’s actually not thought to be the case. Such an event would have destroyed the disk structure that’s seen today; instead, it’s thought that the Sombrero accumulated a lot of extra gas billions of years ago when the Universe was populated with large clouds of gas and dust. The extra gas fell into orbit around the galaxy, eventually spinning into a flattened disk and forming new stars.
This is one of the first galaxies to be seen with such a dual structure — even though M104 has been known about since the mid-1700s.
“Spitzer is helping to unravel secrets behind an object that has been imaged thousands of times,” said Sean Carey of NASA’s Spitzer Science Center at CalTech. “It is intriguing Spitzer can read the fossil record of events that occurred billions of years ago within this beautiful and archetypal galaxy.”
At a magnitude of +8, the Sombrero galaxy is just beyond the limit of naked-eye visibility but can be seen with small telescopes (4-inch/100 mm or larger). It is 28 million light-years away and can be found in the night sky located 11.5° west of Spica and 5.5° northeast of Eta Corvi.
The 'Tornado Nebula.' Credit: NASA / JPL-Caltech / J. Bally (University of Colorado)
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The Spitzer Space Telescope’s Infrared Array Camera (IRAC) is a cool camera, no matter what temperature in which it operates! For 1,000 days now, the camera has been continuously taking images of the Universe – from its most distant regions to our local solar neighborhood. The IRAC is now operating in a “warm” version of its mission, as after more than five-and-a-half years of probing the cool cosmos, in 2009 it ran out of liquid helium coolant that kept its infrared instruments chilled.
“IRAC continues to be an amazing camera, still producing important discoveries and spectacular new images of the infrared universe,” said principal investigator Giovanni Fazio of the Harvard-Smithsonian Center for Astrophysics.
To commemorate 1,000 days of infrared wonders, the program is releasing a gallery of the 10 best IRAC images, featuring images from both the cold and warm portions of its mission. Above is #1: The IRAC has uncovered some mysterious objects like this so-called “tornado” nebula. Because the camera is sensitive to light emitted from shocked molecular hydrogen (seen here in green), astronomers think that this strange beast is the result of an outflowing jet of material from a young star that has generated shock waves in surrounding gas and dust.
See more below:
The Orion Nebula, as seen by Spitzer's IRAC. Credit: NASA / JPL-Caltech / Univ. of Toledo
#2. A ‘warm’ look at the famous nebula in Orion, located about 1,340 light-years from Earth, is actively making new stars today. Although the optical nebula is dominated by the light from four massive, hot young stars, IRAC reveals many other young stars still embedded in their dusty womb. It also finds a long filament of star-forming activity containing thousands of young protostars. Some of these stars may host still-forming planets.
The Helix Nebula. Credit: NASA / JPL-Caltech / J. Hora (CfA) & W. Latter (NASA/Herschel)
#3. After a long life of hydrogen-burning nuclear fusion, stars move into later life states whose details depend on their masses. This IRAC image of the Helix Nebula barely spots the star itself at the center, but clearly shows how the aging star has ejected material into space around it, creating a “planetary nebula.” The Helix Nebula is located 650 light-years away in the constellation Aquarius.
The Trifid Nebula. Credit: NASA / JPL-Caltech
#4. Located 5,400 light-years away in the constellation Sagittarius, the Trifid Nebula appears as a big maze of gas and dust. Here, Spitzer’s IRAC was observing how the processes of stellar evolution affects the surrounding environment. The Trifid Nebula hosts stars at all stages of life, and with images like this, scientists can observe how stars mature.
The 'Mountains of Creation' in the W5 region near Perseus. Credit: NASA / JPL-Caltech / CfA
#5. Within galaxies like the Milky Way, giant clouds of gas and dust coalesce under the influence of gravity until new stars are born. IRAC can both measure the warm dust and peer deeply into it to study the processes at work. In this giant cloud several stellar nurseries can be seen, some still within the tips of the dusty region that has been called the “Mountains of Creation, 7,000 light-years away from Earth.
DR22, in the constellation Cygnus the Swan. Credit: NASA / JPL-Caltech
#6. After blowing away its natal material, the young star cluster seen here emits winds and harsh ultraviolet light that sculpt the remnant cloud into fantastic shapes. Astronomers are not sure when that activity suppresses future star formation by disruption, and when it facilitates star formation through compression. The cluster, known as DR22, is in the constellation Cygnus the Swan.
Spitzer's composite of the entire Milky Way Galaxy. Credit: NASA / JPL-Caltech / E. Churchwell (Univ. of Wisconsin)
#7. IRAC has systematically imaged the entire Milky Way disk, assembling a composite photograph containing billions of pixels with infrared emission from everything in this relatively narrow plane. The image here shows five end-to-end strips spanning the center of our galaxy. This image covers only one-third of the whole galactic plane. Astronomers unveiled a 55-meter version of the image at the AAS meeting in June of 2008, and you can see the entire image on the GLIMPSE (Galactic Legacy Infrared Mid-Plane Survey Extraordinaire) Image Viewer, which provides a great way to view and browse this image.
The Whirlpool Galaxy and its companion. Credit: NASA / JPL-Caltech / R. Kennicutt (Univ. of Arizona)
#8. Collisions play an important role in galaxy evolution. These two galaxies – the Whirlpool and its companion – are relatively nearby at a distance of just 23 million light-years from Earth. IRAC sees the main galaxy as very red due to warm dust – a sign of active star formation that probably was triggered by the collision.
The Sombrero Galaxy. Credit: NASA / JPL-Caltech / R. Kennicutt (Univ. of Arizona)
#9. Star formation helps shape a galaxy’s structure through shock waves, stellar winds, and ultraviolet radiation. In this image of the nearby Sombrero Galaxy, IRAC clearly sees a dramatic disk of warm dust (red) caused by star formation around the central bulge (blue). The Sombrero is located 28 million light-years away in the constellation Virgo.
A field of galaxies, seen by Spitzer's IRAC. Credit: NASA / JPL-Caltech / SWIRE Team
#10. And coming in at #10 is this lovely image showing many points of light. They aren’t stars but entire galaxies. A few, like the mini-tadpole at upper right, are only hundreds of millions of light-years away so their shapes can be discerned. The most distant galaxies are too far away and appear as dots. Their light is seen as it was over ten billion years ago, when the universe was young.
Will we see more from Spitzer? Certainly. NASA’s Senior Review Panel has recommended extending the Spitzer warm mission through 2015.
The MOSFIRE instrument's "first light" image of The Antennae galaxies, acquired on April 4 2012.
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Last week, on April 4, 2012, the W.M. Keck Observatory’s brand-new MOSFIRE instrument opened its infrared-sensing eyes to the Universe for the first time, capturing the image above of a pair of interacting galaxies known as The Antennae. Once fully commissioned and scientific observations begin, MOSFIRE will greatly enhance the imaging abilities of “the world’s most productive ground-based observatory.”
Installed into the Keck I observatory, MOSFIRE — which stands for Multi-Object Spectrometer For Infra-Red Exploration — is able to gather light in infrared wavelengths. This realm of electromagnetic radiation lies just beyond red on the visible spectrum (the “rainbow” of light that our eyes are sensitive to) and is created by anything that emits heat. By “seeing” in infrared, MOSFIRE can peer through clouds of otherwise opaque dust and gas to observe what lies beyond — such as the enormous black hole that resides at the center of our galaxy.
MOSFIRE can also resolve some of the most distant objects in the Universe, in effect looking back in time toward the period “only” a half-billion years after the Big Bang. Because light from that far back has been so strongly shifted into the infrared due to the accelerated expansion of the Universe (a process called redshift) only instruments like MOSFIRE can detect it.
The instrument itself must be kept at a chilly -243ºF (-153ºC) in order to not contaminate observations with its own heat.
Astronomers also plan to use MOSFIRE to search for brown dwarfs — relatively cool objects that never really gained enough mass to ignite fusion in their cores. Difficult to image even in infrared, it’s suspected that our own galaxy is teeming with them.
The impressive new instrument has the ability to survey up to 46 objects at once and then do a quick-change to new targets in just minutes, as opposed to the one to two days it can typically take other telescopes!
Unprocessed image of M82 taken with MOSFIRE on April 5, 2012. (W. M. Keck Observatory)
Images taken on the nights of April 4 and 5 are just the beginning of what promises to be a new heat-seeking era for the Mauna Kea-based observatory!
“The MOSFIRE project team members at Keck Observatory, Caltech, UCLA, and UC Santa Cruz are to be congratulated, as are the observatory operations staff who worked hard to get MOSFIRE integrated into the Keck I telescope and infrastructure,” says Bob Goodrich, Keck Observatory Observing Support Manager. “A lot of people have put in long hours getting ready for this momentous First Light.”
The two Keck 10-meter domes atop Mauna Kea. (Rick Peterson/WMKO)
Read more on the Keck press release here.
The W. M. Keck Observatory operates two 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Big Island of Hawaii. The spectrometer was made possible through funding provided by the National Science Foundation and astronomy benefactors Gordon and Betty Moore.
Centaurus A in Far-infrared and X-rays. Credit: Far-infrared: ESA/Herschel/PACS/SPIRE/C.D. Wilson, MacMaster University, Canada; X-ray: ESA/XMM-Newton/EPIC
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The mysterious galaxy Centaurus A is a great place to study the extreme processes that occur near super-massive black holes, scientists say, and this beautiful new image from the combined forces of the Herschel Space Observatory and the XMM-Newton x-ray satellite reveals energetic processes going on deep in the galaxy’s core. This beautiful image tells a tale of past violence that occurred here.
The twisted disc of dust near the galaxy’s heart shows strong evidence that Centaurus A underwent a cosmic collision with another galaxy in the distant past. The colliding galaxy was ripped apart to form the warped disc, and the formation of young stars heats the dust to cause the infrared glow.
This multi-wavelength view of Centaurus A shows two massive jets of material streaming from a immense black hole in the center. When observed by radio telescopes, the jets stretch for up to a million light years, though the Herschel and XMM-Newton results focus on the inner regions.
At a distance of around 12 million light years from Earth, Centaurus A is the closest large elliptical galaxy to our own Milky Way.
“Centaurus A is the closest example of a galaxy to us with massive jets from its central black hole,” said Christine Wilson of McMaster University, Canada, who is leading the study of Centaurus A with Herschel. “Observations with Herschel, XMM-Newton and telescopes at many other wavelengths allow us to study their effects on the galaxy and its surroundings.”
