A majestic face-on spiral galaxy located deep within the Coma Cluster of galaxies. Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
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The Coma Cluster is a huge, densely populated cluster, with thousands of galaxies closely bunched together. Amid the bedlam of ellipticals, lenticulars and irregulars is this majestic face-on spiral galaxy known as NGC 4911. Hubble stared long and deep to get this highly detailed image of this particular galaxy located deep within the Coma Cluster. Data from three different years and 28 hours of exposure time were combined to capture this breathtaking look at spiral arms, glowing newborn star clusters and iridescent pink clouds of hydrogen, meaning there is ongoing star formation.
The Coma Cluster lies 320 million light-years away in the northern constellation Coma Berenices. As usual for clusters like this, there are only a few young spirals galaxies, and Hubble magnificently captured one of them in all its glory, using long exposure times with the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys.
A new image of two tangled galaxies has been released by NASA's Great Observatories. The Antennae galaxies, located about 62 million light-years from Earth, are shown in this composite image from the Chandra X-ray Observatory (blue), the Hubble Space Telescope (gold and brown), and the Spitzer Space Telescope (red). The Antennae galaxies take their name from the long antenna-like arms seen in wide-angle views of the system. These features were produced in the collision. Image credit: Chandra: NASA/CXC/SAO, Spitzer: NASA/JPL-Caltech, Hubble: NASA/STScI
A new image of two tangled galaxies has been released by NASA’s Great Observatories. The Antennae galaxies, located about 62 million light-years from Earth, are shown in this composite image from the Chandra X-ray Observatory (blue), the Hubble Space Telescope (gold and brown), and the Spitzer Space Telescope (red). The Antennae galaxies take their name from the long, antenna-like arms seen in wide-angle views of the system. These features were produced in the collision.
The collision, which began more than 100 million years ago and is still occurring, has triggered the formation of millions of stars in clouds of dusts and gas in the galaxies. The most massive of these young stars have already sped through their evolution in a few million years and exploded as supernovas.
The X-ray image from Chandra shows huge clouds of hot, interstellar gas, which have been injected with rich deposits of elements from supernova explosions. This enriched gas, which includes elements such as oxygen, iron, magnesium and silicon, will be incorporated into new generations of stars and planets. The bright, point-like sources in the image are produced by material falling onto black holes and neutron stars that are remnants of the massive stars. Some of these black holes may have masses that are almost one hundred times that of the sun.
The Spitzer data show infrared light from warm dust clouds that have been heated by newborn stars, with the brightest clouds lying in the overlap region between the two galaxies. The Hubble data reveal old stars and star-forming regions in gold and white, while filaments of dust appear in brown. Many of the fainter objects in the optical image are clusters containing thousands of stars.
Next time you hear someone complaining that it’s too hot outside, you can make them feel better by pointing out that at least their planet isn’t so hot it is vaporizing into space. Unless of course you happen to be speaking to someone from the gaseous extrasolar planet HD 209458b.
New observations from the Hubble Cosmic Origins Spectrograph (COS) confirm suspicions from 2003 that the planet HD 209458b is behaving like a Jupiter-sized comet, losing its atmosphere in a huge plume due to the powerful solar wind of its too-close star.
HD 209458b is a “hot Jupiter”: a gas giant that orbits extremely close to its star. It whips around its star in 3.5 days, making even speedy little Mercury with its 88 day orbit around the sun look like a slacker.
Astronomers have managed to learn a lot about HD 209458b because it is a transiting planet. That means that its orbit is aligned just right, so from our point of view it blocks some of the light from its star. When that happens, it gives hints at the planet’s size, and gives a much better constraint on the mass. HD 209458b is a little more than two thirds the mass of Jupiter, but heat from its star has puffed it up to two and a half times Jupiter’s diameter.
In the case of HD 209458b, during transits some of the star’s light passes through the planet’s escaping, 2,000-degree-Fahrenheit atmosphere, allowing scientists to tell what it is made of and how fast it is being lost to space.
“We found gas escaping at high velocities, with a large amount of this gas flowing toward us at 22,000 miles per hour,” said astronomer Jeffrey Linsky of the University of Colorado in Boulder, leader of the COS study. “This large gas flow is likely gas swept up by the stellar wind to form the comet-like tail trailing the planet.”
The escaping planetary gases absorbed starlight at wavelengths characteristic of heavier elements like carbon and silicon, suggesting that the star’s intense heat is driving circulation deep in HD 209458b’s atmosphere, dredging up material that would otherwise remain far beneath lighter elements like hydrogen.
Even though its atmosphere is constantly streaming away into space, HD 209458b won’t be disappearing anytime soon. At the measured rate of loss, the planet would last about a trillion years, far longer than the lifetime of its host star.
So, be thankful that even on hot summer days, your planet is in no danger of being vaporized by its star. And if you do happen to be speaking to someone from HD 209458b, you can reassure them that their planet will still be there when they return home. Well, most of it, anyway.
A colorful star-forming region in NGC 2467. Credit: NASA, ESA and Orsola De Marco (Macquarie University)
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OK, that headline doesn’t rhyme, but this incredible new Hubble image looks like a witch’s cauldron of an exotic cosmic brew. It billows with huge clouds of gas and dust and is sprinkled with Eye of Newt, um…er, bright blue hot young stars. These dust clouds in NGC 2467 look like a murky, shadowy liquid, but they are actually star forming regions made mostly of hydrogen, perfect for bubbling up newborn stars. And your little dog, too.
NGC 2467 lies in the southern constellation of Puppis, approximately 13,000 light-years from Earth.
The picture was created from images taken with the Wide Field Channel of the Advanced Camera for Surveys through three different filters (F550M, F660N and F658N, shown in blue, green and red respectively). These data were taken in 2004 but just released today.
This region looks somewhat like the Orion Nebula and the hot young stars that recently formed among this bubbling brew are emitting fierce ultraviolet radiation that is causing the whole scene to glow while also sculpting the environment and gradually eroding the gas clouds. Studies have shown that most of the radiation comes from the single hot and brilliant massive star just above the center of the image. Its fierce radiation has cleared the surrounding region and some of the next generation of stars are forming in the denser regions around the edge.
Hubble image of IRAS 19475+3119. Credit: ESA/Hubble and NASA.
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What a gorgeous new Hubble image! At first glance this object looks like a beautiful, giant, translucent bird. But it is actually star shedding its outer atmosphere. The cloud around this bright star is called IRAS 19475+3119. It lies in the constellation of Cygnus (the Swan) about 15, 000 light-years from Earth in the plane of our Milky Way galaxy.
From the ESA Hubble website:
As stars similar to the Sun age they swell into red giant stars and when this phase ends they start to shed their atmospheres into space. The surroundings become rich in dust and the star is still relatively cool. At this point the cloud shines by reflecting the brilliant light of the central star and the warm dust gives off lots of infrared radiation. It was this infrared radiation that was detected by the IRAS satellite in 1983 and brought the object to the attention of astronomers. Jets from the star may create strange hollow lobes, and in the case of IRAS 19475+3119 two such features appear at different angles. These curious objects are rare and short-lived.
As the star continues to shed material the hotter core is gradually revealed. The intense ultraviolet radiation causes the surrounding gas to glow brilliantly and a planetary nebula is born. The objects that come before planetary nebulae, such as IRAS 19475+3119, are known as preplanetary nebulae, or protoplanetary nebulae. They have nothing to do with planets — the name planetary nebula arose as they looked rather like the outer planets Uranus and Neptune when seen through small telescopes.
This image was created from images taken using the High Resolution Channel of the Hubble Space Telescope’s Advanced Camera for Surveys. The red light was captured through a filter letting through yellow and red light (F606W) and the blue was recorded through a standard blue filter (F435W). The green layer of the image was created by combining the blue and red images. The total exposure times were 24 s and 245 s for red and blue respectively. The field of view is about twenty arcseconds across.
Hubble view of the huge star formation region N11 in the Large Magellanic Cloud. Credit: NASA, ESA and Jesús Maíz Apellániz (Instituto de Astrofísica de Andalucía, Spain).
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Within the Large Magellenic Cloud is one of the most active star forming regions in our nearby Universe. This new Hubble image highlights N11 – also known as the Bean Nebula — a beautiful region of energetic star formation. The billowing pink clouds that look like cotton candy and bright bubbles of glowing gasses and are telltale signs that stars are being created. Click the image for a larger, hi-res version.
Beans, bubbles and candy aren’t the only terrestrial shapes to be found in this spectacular image from the Hubble Space Telescope.
If you zoom into upper left (click this link for a zoom video) you’ll find a rose: The Rose Nebula LHA 120-N 11A. Its rose-like petals of gas and dust are illuminated from within, thanks to the radiation from the massive hot stars at its centre. N11A is relatively compact and dense and is the site of the most recent burst of star development in the region.
If you live in the southern hemisphere, both the Large Magellanic Cloud and its small companion, the Small Magellanic Cloud, are easily seen with the unaided eye. That’s a sight I would someday love to see!
Detailed observations made by the NASA/ESA Hubble Space Telescope have led researchers to believe that the flash of light seen on Jupiter on 3 June was a meteor. Credit: NASA, ESA, M. H. Wong (University of California, Berkeley, USA), H. B. Hammel (Space Science Institute, Boulder, Colorado, USA), A. A. Simon-Miller (Goddard Space Flight Center, Greenbelt, Maryland, USA) and the Jupiter Impact Science Team.
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Jupiter has a few mysteries these days. Between an equatorial belt that has gone missing and an impact that didn’t leave a mark, astronomers decided they needed to put the Hubble Space Telescope on the case. New and detailed observations from the venerable space telescope have provided some insights into these two recent puzzling events.
At 22:31 (CEST) on June 3, 2010 Australian amateur astronomer Anthony Wesley saw a two-second-long flash of light on the disc of Jupiter, captured from a live video feed from his telescope. In the Philippines, amateur astronomer Chris Go confirmed that he had simultaneously recorded the transitory event on video. Wesley was also the discoverer of the now world-famous July 2009 impact.
Astronomers around the world suspected that something significant must have hit the giant planet to unleash a flash of energy bright enough to be seen here on Earth, about 770 million kilometers away. But they didn’t know how just how big it was or how deeply it had penetrated into the atmosphere. Over the past two weeks there have been ongoing searches for the “black-eye” pattern of a deep direct hit like those left by former impactors.
Astronomers turned Hubble’s Wide Field Camera 3 aboard the NASA/ESA Hubble Space Telescope on June 7, and found no sign of debris above Jupiter’s cloud tops. This means that the object didn’t descend beneath the clouds and explode as a fireball. If it had, then dark sooty blast debris would have been ejected and would have rained down onto the clouds.
Instead the flash is thought to have come from a giant meteor burning up high above Jupiter’s cloud tops, which did not plunge deep enough into the atmosphere to explode and leave behind any telltale cloud of debris, as seen in previous Jupiter collisions.
“The cloud tops and the impact site would have appeared dark in the ultraviolet and visible images due to debris from an explosion,” said team member Heidi Hammel of the Space Science Institute in Boulder, Colorado. “We can see no feature that has those distinguishing characteristics in the known vicinity of the impact, suggesting there was no major explosion and no ‘fireball’.”
Dark smudges marred Jupiter’s atmosphere when a series of fragments of Comet Shoemaker-Levy 9 hit Jupiter in July 1994, and a similar dark area formed in July 2009 when a suspected asteroid slammed into Jupiter. The latest intruder is estimated to be only a fraction of the size of these previous impactors and is thought to have been a meteor.
So, Wesley and Go were fortunate to have spotted the flash.
“Observations of these impacts provide a window on the past — onto the processes that shaped our Solar System in its early history,” said team member Leigh Fletcher of the University of Oxford, UK. “Comparing the two collisions — from 2009 and 2010 — will hopefully yield insights into the types of impact processes in the outer Solar System, and the physical and chemical response of Jupiter’s atmosphere to these amazing events.” These Hubble images of Jupiter taken 11 months apart show the Southern Equatorial Belt has disappeared. Credit: NASA, ESA, M. H. Wong (University of California, Berkeley, USA), H. B. Hammel (Space Science Institute, Boulder, Colorado, USA), A. A. Simon-Miller (Goddard Space Flight Center, Greenbelt, Maryland, USA) and the Jupiter Impact Science Team.
Since Hubble was now trained on Jupiter, astronomers used the opportunity to get a close-up look at changes in Jupiter’s atmosphere following the disappearance of the dark cloud feature known as the Southern Equatorial Belt several months ago.
In the Hubble view, a slightly higher altitude layer of white ammonia ice crystal clouds appears to obscure the deeper, darker belt clouds. “Weather forecast for Jupiter’s Southern Equatorial Belt: cloudy with a chance of ammonia,” Hammel said.
The team predicts that these ammonia clouds should clear out in a few months, as they have done in the past. The clearing of the ammonia cloud layer should begin with a number of dark spots like those seen by Hubble along the boundary of the south tropical zone.
“The Hubble images tell us these spots are holes resulting from localized downdrafts. We often see these types of holes when a change is about to occur,” said Amy Simon-Miller from Goddard Space Flight Center. .
“The Southern Equatorial Belt last faded in the early 1970s. We haven’t been able to study this phenomenon at this level of detail before,” Simon-Miller added. “The changes of the last few years are adding to an extraordinary database on dramatic cloud changes on Jupiter.”
If you think about it, spacecraft are kind of ethereal in that once they are launched into space, we don’t ever see them again. Australian artist Peter Hennessey has created life-size wooden sculptures of several different spacecraft, giving people the chance to see and touch these objects that are immediately recognizable but which we will never actually experience. Hennessey says he wanted to “reverse the virtualization of physical things” by creating life-size reproductions of the spacecraft such as the Voyager space probe, Apollo Lunar Rover, the Hubble Space Telescope, and more. From Hennessey’s website: “By ‘re-enacting’ space traveling, scientific and military objects in plywood, galvanized steel and canvas, the artist creates ‘stand-ins’ that allow the viewer to contemplate their physical, symbolic and historical resonances as well as the political processes that they represent.”
I just think they are really cool, and I’d love to see them – Hubble has to be huge! See below.
'My Hubble (the universe turned in on itself)' by artist Peter Hennessey.
“My Hubble (the universe turned in on itself) is now on display in Sydney Australia as part of “Biennale of sydney 2010.” This life size ‘re-enactment’ of the Hubble Space Telescope was constructed “with the aim of giving the viewer a physical experience of the object.” It is constructed from lasercut plywood and steel and simultaneously enacts the scale and detail
of the original. This is an interactive sculpture: visitors are encouraged to play with, modify and create their own mini universes on the ground, which are then reflected by the telescope into the heavens.
According to the Design Bloom website, when creating his work Hennessey looked at 7 different images of the Hubble, and rather than using 3D software to model individual parts as one might expect, he used adobe illustrator. Building the telescope took about 3 months – in which 6 weeks were dedicated to laser cutting individual parts and building them into sections and the rest of the time was dedicated to assembling it.
'My Lunar Rover' by artist Peter Hennessey.
With ‘My Moon Landing’ Hennessey’s wanted to explore the “physicality, presences and symbolic power of the inaccessible objects that derive from the space race.”
These NASA Hubble Space Telescope snapshots reveal an impact scar on Jupiter fading from view over several months between July 2009 and November 2009. Credit: NASA, ESA, M. H. Wong (University of California, Berkeley), H. B. Hammel (Space Science Institute, Boulder, Colo.), I. de Pater (University of California, Berkeley), and the Jupiter Impact Team
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When amateur astronomer Anthony Wesley from Australia saw a dark spot the size of the Pacific Ocean appear on Jupiter through his telescope on July 19, 2009, this started a flurry of astronomic activity, with other telescopes quickly slewing to take a look. It didn’t take long for other astronomers to confirm Jupiter had been hit by an object, either an asteroid or a comet. Of course, the world’s most famous telescope, Hubble, zeroed in on this unexpected activity on Jupiter, and luckily, the telescope had been recently updated with a new Wide Field Camera 3 and newly repaired Advanced Camera for Surveys. Astronomers have now released a series of images from Hubble which may show for the first time the immediate aftermath of an asteroid striking another planet.
Astronomers have witnessed this kind of cosmic event before, but from a comet. Similar scars had been left behind during the course of a week in July 1994, when more than 20 pieces of Comet P/Shoemaker-Levy 9 (SL9) plunged into Jupiter’s atmosphere. The 2009 impact occurred during the same week, 15 years later.
But comparing Hubble images of both collisions, astronomers say the culprit was likely an asteroid about 1,600 feet (500 meters) wide.
“This solitary event caught us by surprise, and we can only see the aftermath of the impact, but fortunately we do have the 1994 Hubble observations that captured the full range of impact phenomena, including the nature of the objects from pre-impact observations” says astronomer Heidi Hammel of the Space Science Institute in Boulder, Colo., leader of the Jupiter impact study.
The analysis revealed key differences between the two collisions (in 1994 and 2009), providing clues to the 2009 event. Astronomers saw a distinct halo around the 1994 impact sites in Hubble ultraviolet (UV) images, evidence of fine dust arising from a comet-fragment strike. The UV images also showed a strong contrast between impact-generated debris and Jupiter’s clouds.
Hubble ultraviolet images of the 2009 impact showed no halo and also revealed that the site’s contrast faded rapidly. Both clues suggest a lack of lightweight particles, providing circumstantial evidence for an impact by a solid asteroid rather than a dusty comet.
The elongated shape of the recent asteroid impact site also differs from the 1994 strike, indicating that the 2009 object descended from a shallower angle than the SL9 fragments. The 2009 body also came from a different direction than the SL9 pieces.
Team member Agustin Sanchez-Lavega of the University of the Basque Country in Bilbao, Spain, and colleagues performed an analysis of possible orbits that the 2009 impacting body could have taken to collide with Jupiter. Their work indicates the object probably came from the Hilda family of bodies, a secondary asteroid belt consisting of more than 1,100 asteroids orbiting near Jupiter.
The 2009 strike was equal to a few thousand standard nuclear bombs exploding, comparable to the blasts from the medium-sized fragments of SL9. The largest of those fragments created explosions that were many times more powerful than the world’s entire nuclear arsenal blowing up at once.
The recent impact underscores the important work performed by amateur astronomers. “This event beautifully illustrates how amateur and professional astronomers can work together,” said Hammel.
The Jupiter bombardments reveal that the solar system is a rambunctious place, where unpredictable events may occur more frequently than first thought. Jupiter impacts were expected to occur every few hundred to few thousand years. Although there are surveys to catalogue asteroids, many small bodies may still go unnoticed and show up anytime to wreak havoc.
The study by Hammel’s team appeared in the June 1 issue of The Astrophysical Journal Letters.
NGC 3603 and its massive compact central star cluster was taken with the Advanced Camera for Surveys (ACS) on the NASA/ESA Hubble Space Telescope. The region that was studied in detail to detect the motion of stars within the cluster is shown as a box. Credit: NASA, ESA and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration
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Using the Hubble Space Telescope, astronomers from the Max Planck Institute for Astronomy made two observations ten years apart of the giant nebula NGC 3603 and found a surprising amount of movement and unrest in one of the most massive young star clusters in the Milky Way. The comparison images reveal several hundred stars continued to move for about 1 million years after the star cluster’s formation, with stellar motion not having “settled down” as expected. This new finding is at odds with current models of how such clusters evolve, and may force astronomers to rethink how star clusters form and develop.
While ordinary star clusters disperse over time as the different stars go their own separate ways, it was thought that very massive and compact clusters were different, and that they formed massive aggregations of stars known as globular clusters, whose tightly-packed stars remain gravitationally bound to each other for billions of years.
Conventional thinking was that stars with lower mass should move faster, and those with higher mass should move more slowly. But a team led by Wolfgang Brander, making high precision observations, found the stars in NGC 3603 are still moving at rates that are independent of their mass.
They found that all of the stars move at about the same average speed of 4.5 km/s (corresponding to a change in apparent position of a mere 140 micro-arc seconds per year). The average speed does not appear to vary with mass at all.
The team observed more than 800 stars and were able to obtain sufficiently precise speed measurements for 234 cluster stars of different masses and surface temperatures. Partial view of the giant nebula (HII region) NGC 3603 with its central, 1 million year old compact starburst cluster. False-color image based on observations with the Wide Field/Planetary Camera 2 of the Hubble Space Telescope. The dominant green color signalizes light emitted as ionized hydrogen regains its missing electron ('recombination line H-alpha'). The field of view is about 160 arc seconds on each side. The image shape is due to the detector placement of the Wide Field/Planetary Camera. Credit: NASA/ESA/Wolfgang Brandner (MPIA), Boyke Rochau (MPIA) and Andrea Stolte (University of Cologne)
“Once our analysis was completed, we reached a precision of 27 millionths of an arc second per year,” said Boyke Rochau, the paper’s lead author. “Imagine you are in Bremen, observing an object that is located in Vienna. Now the object moves sideways by the breadth of a human hair. That’s a change in apparent position of about 27 millionths of an arc second.”
Apparently – and surprisingly – this very massive star cluster has not yet settled down. Instead, the stars’ velocities still reflect conditions from the time the cluster was formed, approximately one million years ago.
“For the first time, we have been able to measure precise stellar motions in such a compact young star cluster. This is key information for astronomers trying to understand how such clusters are formed, and how they evolve,” said team member Andrea Stolte from the University of Cologne.
Vexingly, the question of whether or not the massive young cluster in NGC 3603 will become a globular cluster remains open. Given the new results, it all depends on the speeds of the low-mass stars, which were too faint to allow for precise speed measurements with the Hubble Space Telescope. “To find out whether or not our star cluster will disperse, we will need to wait for the next generation of telescopes, such as the James Webb Space Telescope (JWST) or ESO’s European Extremely Large Telescope (E-ELT),” said Brandner.
The results have been published in the Letters section of the Astrophysical Journal. Read the paper here.
