Early Black Holes were Grazers Rather than Glutonous Eaters

Faint quasars powered by black holes. Image credit NASA/ESA/Yale

Black holes powering distant quasars in the early Universe grazed on patches of gas or passing galaxies rather than glutting themselves in dramatic collisions according to new observations from NASA’s Spitzer and Hubble space telescopes.

A black hole doesn’t need much gas to satisfy its hunger and turn into a quasar, says study leader Kevin Schawinski of Yale “There’s more than enough gas within a few light-years from the center of our Milky Way to turn it into a quasar,” Schawinski explained. “It just doesn’t happen. But it could happen if one of those small clouds of gas ran into the black hole. Random motions and stirrings inside the galaxy would channel gas into the black hole. Ten billion years ago, those random motions were more common and there was more gas to go around. Small galaxies also were more abundant and were swallowed up by larger galaxies.”

Quasars are distant and brilliant galactic powerhouses. These far-off objects are powered by black holes that glut themselves on captured material; this in turn heats the matter to millions of degrees making it super luminous. The brightest quasars reside in galaxies pushed and pulled by mergers and interactions with other galaxies leaving a lot of material to be gobbled up by the super-massive black holes residing in the galactic cores.

Schawinski and his team studied 30 quasars with NASA’s orbiting telescopes Hubble and Spitzer. These quasars, glowing extremely bright in the infrared images (a telltale sign that resident black holes are actively scooping up gas and dust into their gravitational whirlpool) formed during a time of peak black-hole growth between eight and twelve billion years ago. They found 26 of the host galaxies, all about the size of our own Milky Way Galaxy, showed no signs of collisions, such as smashed arms, distorted shapes or long tidal tails. Only one galaxy in the study showed evidence of an interaction. This finding supports evidence that the creation of the most massive black holes in the early Universe was fueled not by dramatic bursts of major mergers but by smaller, long-term events.

“Quasars that are products of galaxy collisions are very bright,” Schawinski said. “The objects we looked at in this study are the more typical quasars. They’re a lot less luminous. The brilliant quasars born of galaxy mergers get all the attention because they are so bright and their host galaxies are so messed up. But the typical bread-and-butter quasars are actually where most of the black-hole growth is happening. They are the norm, and they don’t need the drama of a collision to shine.

“I think it’s a combination of processes, such as random stirring of gas, supernovae blasts, swallowing of small bodies, and streams of gas and stars feeding material into the nucleus,” Schawinski said.

Unfortunately, the process powering the quasars and their black holes lies below the detection of Hubble making them prime targets for the upcoming James Webb Space Telescope, a large infrared orbiting observatory scheduled for launch in 2018.

You can learn more about the images here.

Image caption: These galaxies have so much dust enshrouding them that the brilliant light from their quasars cannot be seen in these images from the NASA/ESA Hubble Space Telescope.

Thierry Legault: One Transit is Not Enough

The transit of the Hubble Space Telescope across the Sun was taken from Queensland, Australia, simultaneously with the 2012 transit of Venus. Credit: Thierry Legault.

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Astrophotographer Thierry Legault had told us he was traveling to Australia for the Transit of Venus, so we knew he had something special planned. But that still didn’t prepare us for the awesomeness of what he has just achieved. During the Transit of Venus, Legault also captured the Hubble Space Telescope moving across the face of the Sun. Not once, but 9 times, during the HST’s transit time of .97 seconds. “Thanks to the continuous shooting mode of the Nikon D4 DSLR running at 10 fps,” Legault said on his website, which shows his new images. Of course, due to the differences in distance from Earth of Hubble vs. Venus, Venus took a lazy 6-plus hours to make its transit. A few giant sunspots also join in the view.

Below see a close-up of the two transits and a look at Legault’s set-up in the Outback of Queensland.

A close-up of Venus and Hubble (tiny black dots just above Venus) transiting the Sun. Credit: Thierry Legault. Used by permission.
Legault's equipment setup for viewing the Venus Transit in Queensland, Australia. Credit: Thierry Legault. Used by permission.

Legault noted that just one of the telescope/camera setups was his. So, he had just one chance of capturing the double transit. And he nailed it.

Here’s the map from CalSky of where the HST transit would be visible, just a thin band across the top of Queensland:

Map from CalSky of the Hubble Transit. Via Thierry Legault.

Legault said he has some more images on the way, including the ring of the atmosphere of Venus around the first contact, images of the transit in H-alpha, and the full ring of Venus 24 hours after the transit, so keep checking his website for more fantastic images.

Congratulations to Thierry Legault for a truly amazing and special capture of the Transit of Venus, something that won’t happen again in our lifetimes. And thanks to Thierry for sharing his images with Universe Today.

Surprise! NASA Gets Two ‘Free’ Hubble-like Space Telescopes

Could two unused satellites given to NASA help resurrect the proposed WFIRST mission? Credit: NASA

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NASA will be getting two unused space surveillance satellites from the US’s National Reconnaissance Office, which could possibly be used to search for dark energy. In articles in the Washington Post and the New York Times, NASA and NRO officials revealed the two unused and not-fully-built satellites are available for NASA to use as they see fit. While the satellites don’t have astronomical instruments and are still in a warehouse, they do have 2.4-meter (7.9 feet) mirrors, just like Hubble, with a wider field of view and a maneuverable secondary mirror that makes it possible to obtain better-focused images.

“This is a total game changer,” said David N. Spergel of Princeton, quoted in the New York Times, who is co-chairman of a committee on astronomy and astrophysics for the National Academy of Sciences.

Reportedly, the NRO contacted NASA in 2011 about the two spy satellites. Since taking over as head of the NASA Science Directorate early this year, former Hubble repairman John Grunsfeld has been working with scientists and other NASA officials to quietly study the possibility of using the two satellites as “repurposed telescopes.”

Originally designed to look at Earth for surveillance, the two telescopes could be turned to look at the heavens instead, as the National Reconnaissance Office said they no longer needed them for spy missions. Why two such spy telescopes were under construction and then scrapped is not clear.

Described as not fully built and some parts being in “bits and pieces,” NASA will have to decide on how they should be used, build additional instruments, launch them, and support the operations.

Reportedly, Grunsfeld and his secret team have come up with a plan to turn one of the telescopes to investigate the mysterious dark energy that is speeding up the expansion of the universe.

NASA officials stressed that they do not have a program or a budget to launch even one telescope at the moment, and that at the very earliest, under favorable budgets, it would be 2020 before even one of the two gifted telescopes could be ready for a mission.

The Washington Post asked Grunsfeld whether anyone at NASA was popping champagne, and he answered, “We never pop champagne here; our budgets are too tight.”

In the latest decadal survey the astronomical community had suggested a dark energy telescope as its top priority in astronomy and astrophysics, but the lack of funding – along with huge cost overruns by the James Webb Space Telescope — made it seem like such a telescope would be an impossibility.

The two telescopes could possibly be used for the proposed WFIRST project, which seemingly was not going anywhere with the latest budget proposal or as a ‘scout’ for the JWST.

“It would be a great discovery telescope for where Webb should look in addition to doing the work on dark energy,” Spergel said in the Washington Post.

Astronomers will be discussing the possibilities at a meeting at the National Academy of Sciences held on today in Washington, D.C. and how they could turn the two gifted telescopes into official missions.

Read more in the Washington Post and the New York Times.

It’s Inevitable: Milky Way, Andromeda Galaxy Heading for Collision

This illustration shows a stage in the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years. In this image, representing Earth's night sky in 3.75 billion years, Andromeda (left) fills the field of view and begins to distort the Milky Way with tidal pull. (Credit: NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger)

Astronomers have known for years that our Milky Way and its closest neighbor, the Andromeda galaxy, (a.k.a M31) are being pulled together in a gravitational dance, but no one was sure whether the galaxies would collide head-on or glide past one another. Precise measurements from the Hubble Space Telescope have now confirmed that the two galaxies are indeed on a collision course, headed straight for a colossal cosmic collision.

No need to panic for the moment, as this is not going to happen for another four billion years. And while astronomers say it is likely the Sun will be flung into a different region of our galaxy, Earth and the solar system will probably just go along for the ride and are in no danger of being destroyed.

“In the ‘worst-case-scenario’ simulation, M31 slams into the Milky Way head-on and the stars are all scattered into different orbits,” said team member Gurtina Besla of Columbia University in New York, N.Y. “The stellar populations of both galaxies are jostled, and the Milky Way loses its flattened pancake shape with most of the stars on nearly circular orbits. The galaxies’ cores merge, and the stars settle into randomized orbits to create an elliptical-shaped galaxy.”

The simulations Besla was talking about came from precise measurements by Hubble, painstakingly determining the motion of Andromeda, looking particularly at the sideways motion of M31, which until now has not been able to be done.

“This was accomplished by repeatedly observing select regions of the galaxy over a five- to seven-year period,” said Jay Anderson of STScI.

Right now, M31 is 2.5 million light-years away, but it is inexorably falling toward the Milky Way under the mutual pull of gravity between the two galaxies and the invisible dark matter that surrounds them both.

Of course, the collision is not like a head-on between two cars that takes place in an instant. Hubble data show that it will take an additional two billion years after the encounter for the interacting galaxies to completely merge under the tug of gravity and reshape into a single elliptical galaxy similar to the kind commonly seen in the local universe.

Astronomers said the stars inside each galaxy are so far apart that they will not collide with other stars during the encounter. However, the stars will be thrown into different orbits around the new galactic center. Simulations show that our solar system will probably be tossed much farther from the galactic core than it is today.

There’s also the complication of M31’s small companion, the Triangulum galaxy, M33. This galaxy will join in the collision and perhaps later merge with the M31/Milky Way pair. There is a small chance that M33 will hit the Milky Way first.

The astronomers working on this project said that they were able to make the precise measurements because of the upgraded cameras on Hubble, installed during the final servicing mission. This gave astronomers a long enough time baseline to make the critical measurements needed to nail down M31’s motion.

The Hubble observations and the consequences of the merger are reported in three papers that will appear in an upcoming issue of the Astrophysical Journal.

This series of photo illustrations shows the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy. Credit: NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas, and A. Mellinger

First Row, Left: Present day.
First Row, Right: In 2 billion years the disk of the approaching Andromeda galaxy is noticeably larger.
Second Row, Left: In 3.75 billion years Andromeda fills the field of view.
Second Row, Right: In 3.85 billion years the sky is ablaze with new star formation.
Third Row, Left: In 3.9 billion years, star formation continues.
Third Row, Right: In 4 billion years Andromeda is tidally stretched and the Milky Way becomes warped.
Fourth Row, Left: In 5.1 billion years the cores of the Milky Way and Andromeda appear as a pair of bright lobes.
Fourth Row, Right: In 7 billion years the merged galaxies form a huge elliptical galaxy, its bright core dominating the nighttime sky.

Source: HubbleSite See more images and videos here and here.

How the Hubble Telescope Will Look at the Moon to See Venus Transit the Sun

Scientists used the Hubble Space Telescope to look at the Moon to prepare for special observations of the 2012 Venus transit of the Sun. Credit: NASA, ESA, and D. Ehrenreich (Institut de Planetologie et d'Astrophysique de Grenoble (IPAG)/CNRS/Universite Joseph Fourier)

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Venus moving across the face of the Sun, from our vantage point here on Earth, is such a rare event, that astronomers and observatories around the world have been preparing for this year’s Venus Transit, on June 5-6. And one observatory that is literally “around the world,” – the Hubble Space Telescope — is even planning to make observations of this transit event. What, you say? The Hubble telescope can’t look at the Sun – it would fry every component on board! Hubble scientists are being pretty sneaky, if not resourceful so they too can join in the observations.

Since Hubble can’t look at the Sun directly, astronomers are planning to point the telescope at the Moon, using it as a mirror to capture reflected sunlight and isolate the small fraction of the light that passes through Venus’s atmosphere. Imprinted on that small amount of light are the fingerprints of the planet’s atmospheric makeup.

Scientists say these observations will mimic a technique that is already being used to sample the atmospheres of giant planets outside our solar system passing in front of their stars. In the case of the Venus transit observations, astronomers already know the chemical makeup of Venus’s atmosphere, and that it does not show signs of life on the planet. But the Venus transit will be used to test whether this technique will have a chance of detecting the very faint fingerprints of an Earth-like planet, even one that might be habitable for life, outside our solar system that similarly transits its own star.

Venus is an excellent stand in for Earth because of how similar in size and mass it is to our planet.

Several different instruments on Hubble will be used in this special observation. The Advanced Camera for Surveys, Wide Field Camera 3, and Space Telescope Imaging Spectrograph, to view the transit in a range of wavelengths, from ultraviolet to near-infrared light. During the transit, Hubble will snap images and perform spectroscopy, dividing the sunlight into its constituent colors, which could yield information about the makeup of Venus’s atmosphere.

Hubble will observe the Moon for seven hours, before, during, and after the transit so the astronomers can compare the data. Astronomers need the long observation because they are looking for extremely faint spectral signatures. Only 1/100,000th of the sunlight will filter through Venus’s atmosphere and be reflected off the Moon.

Because the astronomers only have one shot at observing the transit, they had to carefully plan how the study would be carried out. Part of their planning included the test observations of the Moon, such as when they took the top image of Tycho Crater.

Hubble will need to be locked onto the same location on the Moon for more than seven hours, the transit’s duration. For roughly 40 minutes of each 96-minute orbit of Hubble around the Earth, the Earth occults Hubble’s view of the Moon. So, during the test observations, the astronomers wanted to make sure they could point Hubble to precisely the same target area.

This is the last time this century sky watchers can view Venus passing in front of the Sun. The next transit won’t happen until 2117. Venus transits occur in pairs, separated by eight years. The last event was witnessed in 2004.

Find more on how you can observe the Venus transit for yourself in this article by Tammy Plotner.

Source: HubbleSite

The Best of Hubble: 22 Years of Amazing Images

Hubble Space Telescope Image Gallery
The Hubble Space Telescope
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22 years ago today, the Hubble Space Telescope launched into orbit. After overcoming initial problems, Hubble has gone on to become legendary, helping scientists to rewrite astronomy textbooks. To celebrate Hubble’s 22nd anniversary, here’s a slideshow from ESA’s Hubblecast that shows some of the best images from over two decades in orbit, set to specially commissioned music.

Here’s a list of the images shown and their descriptions:
Continue reading “The Best of Hubble: 22 Years of Amazing Images”

Special New Panorama Celebrates Hubble’s 22nd Anniversary

A mosaic view of 30 Doradus, assembled from Hubble Space Telescope photos, Credit: NASA, ESA, ESO,

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Happy birthday to the Hubble Space Telescope! On April 24, 1990, HST was launched into low Earth orbit. Now, nearly 22 years later, Hubble is still producing incredible, stunning images of the farthest reaches of the Universe. For this year’s anniversary, the Hubble team took a special panoramic view of 30 Doradus, a raucous stellar breeding ground, located in the heart of the Tarantula nebula. The image comprises one of the largest mosaics ever assembled from Hubble photos and consists of observations taken by Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys, combined with observations from the European Southern Observatory’s MPG/ESO 2.2-metre telescope that trace the location of glowing hydrogen and oxygen.

The Tarantula nebula is 170,000 light-years away in the Large Magellanic Cloud, a small, satellite galaxy of our Milky Way. No known star-forming region in our galaxy is as large or as prolific as 30 Doradus.

The stars in this image add up to a total mass millions of times bigger than that of our Sun. The image is roughly 650 light-years across and contains some rambunctious stars, from one of the fastest rotating stars to the speediest and most massive runaway star.

The nebula is close enough to Earth that Hubble can resolve individual stars, giving astronomers important information about the stars’ birth and evolution. Many small galaxies have more spectacular starbursts, but the Large Magellanic Cloud’s 30 Doradus is one of the only star-forming regions that astronomers can study in detail. The star-birthing frenzy in 30 Doradus may be partly fueled by its close proximity to its companion galaxy, the Small Magellanic Cloud.

The image reveals the stages of star birth, from embryonic stars a few thousand years old still wrapped in dark cocoons of dust and gas to behemoths that die young in supernova explosions. 30 Doradus is a star-forming factory, churning out stars at a furious pace over millions of years. The Hubble image shows star clusters of various ages, from about 2 million to about 25 million years old.

The image was made from 30 separate fields, 15 from each camera. Hubble made the observations in October 2011. Both cameras were making observations at the same time.

Take an interactive tour of the Tarantula Nebula at the HubbleSite

Source: ESA’s Hubble website

Hubble Spots Mysterious Dark Matter ‘Core’

This composite image shows the distribution of dark matter, galaxies, and hot gas in the core of the merging galaxy cluster Abell 520, formed from a violent collision of massive galaxy clusters. Image Credit: NASA, ESA, CFHT, CXO, M.J. Jee (University of California, Davis), and A. Mahdavi (San Francisco State University)

[/caption]Astronomers are left scratching their heads over a new observation of a “clump” of dark matter apparently left behind after a massive merger between galaxy clusters. What is so puzzling about the discovery is that the dark matter collected into a “dark core” which held far fewer galaxies than expected. The implications of this discovery present challenges to current understandings of how dark matter influences galaxies and galaxy clusters.

Initially, the observations made in 2007 were dismissed as bad data. New data obtained by the Hubble Space Telescope in 2008 confirmed the previous observations of dark matter and galaxies parting ways. The new evidence is based on observations of a distant merging galaxy cluster named Abell 520. At this point, astronomers have a challenge ahead of them in order to explain why dark matter isn’t behaving as expected.

“This result is a puzzle,” said astronomer James Jee (University of California, Davis). “Dark matter is not behaving as predicted, and it’s not obviously clear what is going on. Theories of galaxy formation and dark matter must explain what we are seeing.”

Current theories on dark matter state that it may be a kind of gravitational “glue” that holds galaxies together. One of the other interesting properties of dark matter is that by all accounts, it’s not made of same stuff as people and planets, yet interacts “gravitationally” with normal matter. Current methods to study dark matter are to analyze galactic mergers, since galaxies will interact differently than their dark matter halos. The current theories are supported by visual observations of galaxy mergers in the Bullet Cluster, and have become a classic example of our current understanding of dark matter.

Studies of Abell 520 are causing astronomers to think twice about our current understanding of dark matter. Initial observations found dark matter and hot gas, but lacked luminous galaxies – which are normally detected in the same regions as dark matter concentrations. Attempting to make sense of the observations, the astronomers used Hubble’s Wide Field Planetary Camera 2 to map dark matter in the cluster using a gravitational lensing technique.

“Observations like those of Abell 520 are humbling in the sense that in spite of all the leaps and bounds in our understanding, every now and then, we are stopped cold,” said Arif Babul (University of Victoria, British Columbia).

Jee added, “We know of maybe six examples of high-speed galaxy cluster collisions where the dark matter has been mapped, but the Bullet Cluster and Abell 520 are the two that show the clearest evidence of recent mergers, and they are inconsistent with each other. No single theory explains the different behavior of dark matter in those two collisions. We need more examples.”

The team has worked on numerous possibilities for their findings, each with their own set of unanswered questions. One such possibility is that Abell 520 was a more complicated merger than the Bullet Cluster encounter. There may have been several galaxies merging in Abell 520 instead of the two responsible for the Bullet Cluster. Another possibility is that like well-cooked rice, dark matter may be sticky. When particles of ordinary matter collide, they lose energy and, as a result, slow down. It may be possible for some dark matter to interact with itself and remain behind after a collision between two galaxies.

Another possibility may be that there were more galaxies in the core, but were too dim for Hubble to detect. Being dimmer, the galaxies would have formed far fewer stars than other types of galaxies. The team plans to use their Hubble data to create computer simulations of the collision, in the hopes of obtaining vital clues in the efforts to better understand the unusual behavior of dark matter.

If you’d like to learn more about the Hubble Space Telescope, visit: http://www.nasa.gov/hubble

More Details from Hubble Reveal Strange Exoplanet is a Steamy Waterworld

GJ1214b, shown in this artist’s view, is a super-Earth orbiting a red dwarf star 40 light-years from Earth. Credit: NASA, ESA, and D. Aguilar (Harvard-Smithsonian Center for Astrophysics)

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Would Kevin Costner’s character in the movie “Waterworld” be at home on this exoplanet? The planet GJ 1214b was discovered in 2009 and was one of the first planets where an atmosphere was detected. In 2010, scientists were able to measure the atmosphere, finding it likely was composed mainly of water. Now, with infrared spectra taken during transit observations by the Hubble Space Telescope, scientists say this world is even more unique, and that it represents a new class of planet: a waterworld underneath a thick, steamy atmosphere.

“GJ 1214b is like no planet we know of,” said Zachary Berta of the Harvard-Smithsonian Center for Astrophysics (CfA). “A huge fraction of its mass is made up of water.”

GJ 1214b is a super-Earth — smaller than Uranus but larger than Earth — and is about 2.7 times Earth’s diameter. That gives it a volume 20 times as great as Earth yet it has less than seven times as much mass, so it’s actually kind of a lightweight. This world is also hot: it orbits a red-dwarf star every 38 hours at a distance of 2 million kilometers, giving it an estimated temperature of 230 degrees Celsius.

Berta and a team of international astronomers used Hubble’s Wide Field Camera 3 (WFC3) to study GJ 1214b when it crossed in front of its host star. During such a transit, the star’s light is filtered through the planet’s atmosphere, giving clues to the mix of gases.

“We’re using Hubble to measure the infrared color of sunset on this world,” Berta said.

Hazes are more transparent to infrared light than to visible light, so the Hubble observations help to tell the difference between a steamy and a hazy atmosphere. They found the spectrum of GJ 1214b to be featureless over a wide range of wavelengths, or colors. The atmospheric model most consistent with the Hubble data is a dense atmosphere of water vapor.

Since the planet’s mass and size are known, astronomers can calculate the density, of only about 2 grams per cubic centimetre. Water has a density of 1 gram per cubic centimetre, while Earth’s average density is 5.5 grams per cubic centimetre. This suggests that GJ 1214b has much more water than Earth does, and much less rock.

As a result, the internal structure of GJ 1214b would be extraordinarily different from that of our world.

“The high temperatures and high pressures would form exotic materials like ‘hot ice’ or ‘superfluid water’, substances that are completely alien to our everyday experience,” Berta said.

Theorists expect that GJ 1214b formed further out from its star, where water ice was plentiful; later the planet migrated inward towards the star. In the process, it would have passed through the star’s habitable zone, where surface temperatures would be similar to Earth’s. How long it lingered there is unknown.

GJ 1214b is located in the constellation of Ophiuchus (The Serpent Bearer), and just 40 light-years from Earth. Scientists say it will be a prime candidate for study by the NASA/ESA/CSA James Webb Space Telescope, planned for launch later this decade.

This article was updated on Feb. 23

Read the team’s paper (pdf).

Source: ESA Hubble

Hubble Captures Giant Lensed Galaxy Arc

Thanks to the presence of a natural "zoom lens" in space, this is a close-up look at the brightest distant "magnified" galaxy in the universe known to date. Credit: NASA, ESA, J. Rigby (NASA Goddard Space Flight Center), K. Sharon (Kavli Institute for Cosmological Physics, University of Chicago), and M. Gladders and E. Wuyts (University of Chicago)

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Less than a year ago, the Hubble Space Telescope’s Wide Field Camera 3 captured an amazing image – a giant lensed galaxy arc. Gravitational lensing produces a natural “zoom” to observations and this is a look at one of the brightest distant galaxies so far known. Located some 10 billion light years away, the galaxy has been magnified as a nearly 90-degree arc of light against the galaxy cluster RCS2 032727-132623 – which is only half the distance. In this unusual case, the background galaxy is over three times brighter than typically lensed galaxies… and a unique look back in time as to what a powerful star-forming galaxy looked like when the Universe was only about one third its present age.

A team of astronomers led by Jane Rigby of NASA’s Goddard Space Flight Center in Greenbelt, Maryland are the parties responsible for this incredible look back into time. It is one of the most detailed looks at an incredibly distant object to date and their results have been accepted for publication in The Astrophysical Journal, in a paper led by Keren Sharon of the Kavli Institute for Cosmological Physics at the University of Chicago. Professor Michael Gladders and graduate student Eva Wuyts of the University of Chicago were also key team members.

“The presence of the lens helps show how galaxies evolved from 10 billion years ago to today. While nearby galaxies are fully mature and are at the tail end of their star-formation histories, distant galaxies tell us about the universe’s formative years. The light from those early events is just now arriving at Earth.” says the team. “Very distant galaxies are not only faint but also appear small on the sky. Astronomers would like to see how star formation progressed deep within these galaxies. Such details would be beyond the reach of Hubble’s vision were it not for the magnification made possible by gravity in the intervening lens region.”

This graphic shows a reconstruction (at lower left) of the brightest galaxy whose image has been distorted by the gravity of a distant galaxy cluster. The small rectangle in the center shows the location of the background galaxy on the sky if the intervening galaxy cluster were not there. The rounded outlines show distinct, distorted images of the background galaxy resulting from lensing by the mass in the cluster. The image at lower left is a reconstruction of what the lensed galaxy would look like in the absence of the cluster, based on a model of the cluster's mass distribution derived from studying the distorted galaxy images. Illustration Credit: NASA, ESA, and Z. Levay (STScI) Science Credit: NASA, ESA, J. Rigby (NASA Goddard Space Flight Center), K. Sharon (Kavli Institute for Cosmological Physics, University of Chicago), and M. Gladders and E. Wuyts (University of Chicago)

But the Hubble isn’t the only eye on the sky examining this phenomenon. A little over 10 years ago a team of astronomers using the Very Large Telescope in Chile also measured and examined the arc and reported the distant galaxy seems to be more than three times brighter than those previously discovered. However, there’s more to the picture than meets the eye. Original images show the magnified galaxy as hugely distorted and it shows itself more than once in the foreground lensing cluster. The challenge was to create a image that was “true to life” and thanks to Hubble’s resolution capabilities, the team was able to remove the distortions from the equation. In this image they found several incredibly bright star-forming regions and through the use of spectroscopy, they hope to better understand them.

Original Story Source: Hubble News Release.