NASA ESA Hubble: Extreme Deep Field images in the farthest reaches of the universe

NASA scientists have directed the Hubble Space Telescope to inspect a tiny patch of sky with an unusually long exposure time to obtain the deepest image of the sky ever obtained. 

The image, dubbed the "Hubble Extreme Deep Field (XDF)", reveals the faintest and most distant galaxies ever detected, shedding more light on the early history of the universe.

Credit: NASA/ESA Hubble

Nine years ago, NASA decided to point Hubble at a seemingly empty, randomly chosen spot in the sky – no larger than a needle's eye at arm's length – and have it gather data over one millions seconds in total exposure.

The result was the iconic image dubbed the "Hubble Ultra-Deep Field" (HUDF)" which, even in a space that small, revealed in excess of ten thousand galaxies.



Now, NASA has done it again, taking the experiment to new levels. With XDF, NASA took a patch of sky within the original Hubble Ultra Deep Field and doubled the exposure time to a total of two million seconds, or an impressive 23 days.

Despite a much narrower field of view, the new picture shows 5500 galaxies in even greater detail, including the earliest we have ever observed.

Images from NASA's Wide-field Infrared Survey Explorer (WISE) reveal an old star in the throes of a fiery outburst, spraying the cosmos with dust.

The findings offer a rare, real-time look at the process by which stars like our sun seed the universe with building blocks for other stars, planets and even life.

 The star, catalogued as WISE J180956.27-330500.2, was discovered in images taken during the WISE survey in 2010, the most detailed infrared survey to date of the entire celestial sky.

It stood out from other objects because it glowed brightly with infrared light. When compared to images taken more than 20 years ago, astronomers found the star was 100 times brighter.

"We were not searching specifically for this phenomenon, but because WISE scanned the whole sky, we can find such unique objects," said Poshak Gandhi of the Japan Aerospace Exploration Agency (JAXA), lead author of a new paper to be published in the Astrophysical Journal Letters.

Results indicate the star recently exploded with copious amounts of fresh dust, equivalent in mass to our planet Earth. The star is heating the dust and causing it to glow with infrared light.

"Observing this period of explosive change while it is actually ongoing is very rare," said co-author Issei Yamamura of JAXA.

"These dust eruptions probably occur only once every 10,000 years in the lives of old stars, and they are thought to last less than a few hundred years each time. It's the blink of an eye in cosmological terms."

The aging star is in the "red giant" phase of its life. Our own sun will expand into a red giant in about 5 billion years.

When a star begins to run out of fuel, it cools and expands. As the star puffs up, it sheds layers of gas that cool and congeal into tiny dust particles.

This is one of the main ways dust is recycled in our universe, making its way from older stars to newborn solar systems.

The other way, in which the heaviest of elements are made, is through the deathly explosions, or supernovae, of the most massive stars.

"It's an intriguing glimpse into the cosmic recycling program," said Bill Danchi, WISE program scientist at NASA Headquarters in Washington. "Evolved stars, which this one appears to be, contribute about 50 percent of the particles that make up humans."

The Stars as Viewed from the International Space Station - Video

The Stars as Viewed from the International Space Station. from AJRCLIPS on Vimeo.

The Stars as Viewed from the International Space Station.

Antlia dwarf galaxy peppers the sky with stars

The myriad faint stars that comprise the Antlia Dwarf galaxy are more than four million light-years from Earth, but this NASA/ESA Hubble Space Telescope image offers such clarity that they could be mistaken for much closer stars in our own Milky Way.

This very faint and sparsely populated small galaxy was only discovered in 1997.

This image was created from observations in visible and infrared light taken with the Wide Field Channel of Hubble’s Advanced Camera for Surveys. The field of view is approximately 3.2 by 1.5 arcminutes.

Although small, the Antlia Dwarf is a dynamic site featuring stars at many different stages of evolution, from young to old.

The freshest stars are only found in the central regions where there is significant ongoing star formation. Older stars and globular clusters are found in the outer areas.

It is not entirely clear whether the Antlia Dwarf is a member our galactic neighborhood, called the Local Group.

It probably lies just beyond the normally accepted outer limits of the group. Although it is fairly isolated, some believe it has interacted with other star groups.

NGC 3109

Evidence comes from the small, spiral, irregular galaxy, NGC 3109, close to the Antlia Dwarf (shown visible in this second image).

Both galaxies feature rifts of stars moving at comparable velocities; a telltale sign that they were gravitationally linked at some point in the past.

NASA Spitzer Telescope Image: Hidden Jet

Spitzer Image HH-34

NASA's Spitzer Space Telescope took this image of a baby star sprouting two identical jets (green lines emanating from fuzzy star).

The jet on the right had been seen before in visible-light views, but the jet at left, the identical twin to the first jet, could only be seen in detail with Spitzer's infrared detectors (IRAC).

The left jet was hidden behind a dark cloud, which Spitzer can see through.



The twin jets, in a system called Herbig-Haro 34 (HH-34), are made of identical knots of gas and dust, ejected one after another from the area around the star.

By studying the spacing of these knots, and knowing the speed of the jets from previous studies, astronomers were able to determine that the jet to the right of the star punches its material out 4.5 years later than the counter-jet.

Hubble Images

The new data also reveal that the area from which the jets originate is contained within a sphere around the star, with a radius of 3 astronomical units.

An astronomical unit is the distance between Earth and the sun. Previous studies estimated that the maximum size of this jet-making zone was 10 times larger.

The wispy material is gas and dust. Arc-shaped bow shocks can be seen at the ends of the twin jets. The shocks consist of compressed material in front of the jets.

The Herbig-Haro 34 (HH-34) jets are located at approximately 1,400 light-years away in the Orion constellation.

Image Credit: NASA/JPL-Caltech

The star factory: observing Arp 220

This star forming core of Arp 220 is only about 3,000 light years across, compared to our own galaxy which measures about 60,000 light years.

The galaxy Arp 220 is home to several giant star clusters-about 10 million solar masses-that are twice as massive as any comparable star cluster in the Milky Way Galaxy.

McMaster University's Christine Wilson is captivated by this turbulent galaxy that provides such a target-rich environment for watching stars form.

The reason that star formation is going wild is that the galaxy is in the late stages of a merger between two larger galaxies.

"This is a nearby look at a phenomenon that was common in the early universe, when many galaxies were merging," says Wilson.

At this week's meeting of the American Association for the Advancement of Science (AAAS) in Vancouver, Wilson will be presenting findings on Arp 220's dazzling rate of star formation-200 times faster than our own Milky Way.

What's more, it's all happening in a much smaller space. The star forming core of Arp 220 is only about 3,000 light years across, compared to our own galaxy which measures about 60,000 light years.

Using the Herschel Space Observatory, an orbiting telescope, Wilson's group has found Arp 220 to have large amounts of very warm molecular hydrogen gas, a surprising find that implies molecular hydrogen is the dominant coolant in the high-temperature gas.

Wilson's team has also observed a massive wind from the centre of the galaxy, removing molecular gas from the central star forming core.

Eta Carinae: Echoes of the Ancient 'Great Eruption' Reach Astronomers

When the binary star system Eta Carinae experienced a spectacular outburst in 1837, dubbed the "Great Eruption," there were no cameras or other sophisticated scientific instruments around to record the event for posterity.

But now, 170 years later, remnants of light from the Great Eruption are finally reaching Earth, providing new insight into how massive stars behave when they are on the brink of exploding.

Astrophysicists at the University of California, Santa Barbara and the Las Cumbres Observatory Global Telescope Network, announced the detection of this "light echo" in a Feb. 16 letter to the journal Nature.

UCSB Postdoc Federica Bianco, who compared the light echo to eyewitness reports from the 1800s, phrased the phenomenon best: "You are at the stadium, watching the game, and your team scores. But you do not have modern instruments, detectors and spectrographs to study it," she said in a press release.

"Now we are getting a replay -- an up-close detailed view of our cosmic eruption," she continued. "And just like with the replay, we get to see the outburst from a different point of view, as the light that we see now was originally traveling in a different direction than the light seen in the 1840s."

Eta Carinae is a rare, massive binary star, and the dominant partner in this cosmic coupling belongs to the class of luminous blue variable stars. When it erupted 170 years ago, it became one of the brightest stars in the sky for a time. So why are we suddenly seeing light from that event again?

The astrophysicists explain that originally, the light traveled away from Earth, and then bounced off dust clouds, which rerouted it to Earth -- just like an echo. The longer path means we are only now seeing that echo.


There might not be photographs, but there are a few historical eyewitness accounts on record to help astrophysicists determine that what they are seeing really is a "light echo" from Eta Carinae's 19th century outburst.

Star Maps From Mobile App Maker Brings Astronomy to the Masses

Skywatching enthusiasts, rejoice! The makers of a popular astronomy app have released a series of free star maps and new educational tools to help both casual and more experienced stargazers learn more about the cosmos, the app's designers said.

Starmap is providing users with free customizable regional star maps and an infographic that illustrates the history of astronomy, and includes resources can be downloaded from the company's website.

The resources join the ranks of a growing field of space-themed apps for digital devices.

"You can download the map month-by-month for the Northern and Southern hemisphere, and you can see the exact times on a list of what can be seen with the naked eye or with telescopes," Frederick Descamps, an astronomer and the creator of the Starmap mobile app, told SPACE.com.

Once users select their hemisphere, region and desired time of night, the map is automatically generated and highlights constellations, planets, moon phases and other cosmic objects that could be visible.

The maps will also separate objects that can be seen with the naked eye, binoculars, small telescopes and larger telescopes.

NASA WISE Image: Cosmic clouds bubbling with new star birth

A new, large mosaic from NASA's Wide-Field Infrared Survey Explorer (WISE) showcases a vast stretch of cosmic clouds bubbling with new star birth.

The region - a 1,000-square-degree chunk of our Milky Way galaxy - is home to numerous star-forming clouds, where massive stars have blown out bubbles in the gas and dust.

"Massive stars sweep up and destroy their natal clouds, but they continuously spark new stars to form along the way," said WISE Mission Scientist Dave Leisawitz of NASA Goddard Space Flight Center, Greenbelt, Md. Leisawitz is co-author of a new paper reporting the results in the Astrophysical Journal.

"Occasionally a new, massive star forms, perpetuating the sequence of events and giving rise to the dazzling fireworks display seen in this WISE mosaic."

The WISE space telescope mapped the entire sky two times in infrared light, completing its survey in February of 2011. Astronomers studying how stars form took advantage of WISE's all-encompassing view by studying several star-forming clouds, or nebulae, including 10 pictured in this new view.

The observations provide new evidence for a process called triggered star formation, in which the winds and sizzling radiation from massive stars compress gas and dust, inducing a second generation of stars. The same winds and radiation carve out the cavities, or bubbles, seen throughout the image.

Finding evidence for triggered star formation has proved more difficult than some might think. Astronomers are not able to watch the stars grow and evolve like biologists watching zebras in the wild.

Instead, they piece together a history of star formation by looking at distinct stages in the process. It's the equivalent of observing only baby, middle-aged and elderly zebras with crude indicators of their ages. WISE is helping to fill in these gaps by providing more and more "specimens" for study.

"Each region we looked at gave us a single snapshot of star formation in progress," said Xavier Koenig, lead author of the new study at Goddard, who presented the results in Austin, Texas, at the 219th meeting of the American Astronomical Society. "But when we look at a whole collection of regions, we can piece together the chain of events."

After looking at several of the star-forming nebulae, Koenig and his colleagues noticed a pattern in the spatial arrangement of newborn stars. Some were found lining the blown-out cavities, a phenomenon that had been seen before, but other new stars were seen sprinkled throughout the cavity interiors.

The results suggest that stars are born in a successive fashion, one after the other, starting from a core cluster of massive stars and moving steadily outward. This lends support to the triggered star formation theory, and offers new clues about the physics of the process.

The astronomers also found evidence that the bubbles seen in the star-forming clouds can spawn new bubbles. In this scenario, a massive star blasts away surrounding material, eventually triggering the birth of another star massive enough to carve out its own bubble. A few examples of what may be first- and second-generation bubbles can be seen in the new WISE image.

"I can almost hear the stars pop and crackle," said Leisawitz.

Study Claims Every Star has Exoplanets around

Every star twinkling in the night sky plays host to at least one planet, a new study suggests.

That implies there are some 10 billion Earth-sized planets in our galaxy.

Using a technique called gravitational microlensing, an international team found a handful of exoplanets that imply the existence of billions more.

The findings were released at the 219th American Astronomical Society (AAS) meeting, alongside reports of the smallest "exoplanets" ever discovered.

Gravitational microlensing is a method that uses the gravity of a far-flung star to amplify the light from even more distant stars that have planets.

Astronomers used a number of relatively small telescopes that make up the Microlensing Network for the Detection of Small Terrestrial Exoplanets, or Mindstep, to look for the rare event of one star passing directly in front of another as seen from Earth.

The team witnessed 40 of these microlensing events, and in three instances spotted the effects of planets circling the more distant stars.

While the number of actual events and detected planets was low, the team was able to estimate how many such exoplanets must exist.

Most news of exoplanets in recent years has come from the Kepler telescope, which spots planets by looking for the slight dimming of their host stars' light as planets pass in front of them.

That method is better at finding large planets close to their host stars.

While a more difficult effect to catch, gravitational microlensing is better at finding planets of all sizes and distances.

It can currently spot a planet as small as Mercury, orbiting at a similar distance to its host star, or as far away as Saturn.

The study, also published in the journal Nature, was a collaboration between researchers from more than 20 international institutes and universities.

"Just the recent 15 years have seen the count of known planets beyond the Solar System rising from none to about 700, but we can expect hundreds of billions to exist in the Milky Way alone," said co-author Dr Martin Dominik, from the University of St Andrews, UK.

Read more of this article here: Exoplanets are around every star, study suggests

Subaru Telescope Confirms Signs of Unseen Planets in Dust Ring of HR 4796 A

Near-infrared (1.6 micron) image of the debris ring around the star HR 4796 A.

An astronomical unit (AU) is a unit of length that corresponds to the average distance between the Earth and Sun, almost 92 million miles (over 149 million km).

The ring consists of dust grains in a wide orbit (roughly twice the size of Pluto's orbit) around the central star.

Its edge is so precisely revealed that the researchers could confirm a previously suspected offset between the ring's center and the star's location.

This "wobble" in the dust's orbit is most likely caused by the unbalancing action of, so far undetected, massive planets likely to be orbiting within the ring.

Furthermore, the image of the ring appears to be smudged out at its tips and reveals the presence of finer dust extending out beyond the main body of the ring.

The SEEDS (Strategic Exploration of Exoplanets and Disks with Subaru Telescope/HiCIAO) project, a five-year international collaboration launched in 2009 and led by Motohide Tamura of NAOJ (National Astronomical Observatory of Japan) has yielded another impressive image that contributes to our understanding of the link between disks and planet formation.

Researchers used Subaru's planet-finder camera, HiCIAO (High Contrast Instrument for the Subaru Next Generation Adaptive Optics), to take a crisp high-contrast image of the dust ring around HR 4796 A, a young (8-10 million years old) nearby star, only 240 light years away from Earth.

The ring consists of dust grains in a wide orbit, roughly twice the size of Pluto's orbit, around the central star.

The resolution of the image of the inner edge of the ring is so precise that an offset between its center and the star's position can be measured.

Although data from the Hubble Space Telescope led another research group to suspect such an offset, the Subaru data not only confirm its presence but also reveal it to be larger than previously assumed.

UK BBC Stargazing Guide - PDF

Click on the picture to see the full 14 page guide

Massive Blue Stars: Ambient molecular gas

Credit: Canada-France-Hawaii Telescope/Coelum

Young massive bright blue stars illuminate the ambient molecular gas of NGC 7129 (top right), a spent star formation region in this image posted on Dec. 21.

The star cluster NGC 7132 (lower left) has existed far longer, and already freed itself from a nascent shroud of gas.

Some young Milky Way stars may be much older

The new analysis shows that stars over a wide range of masses in Upper Scorpius - from slightly more massive than our Sun, up to the mass of the bright star Antares (17 times the mass of our Sun) are giving ages consistent with a mean age of 11 million years.

Low in the south in the summer sky shines the constellation Scorpius and the bright, red supergiant star Antares. Many of the brightest stars in Scorpius, and hundreds of its fainter stars, are among the youngest stars found near the earth, and a new analysis of them may result in a rethinking of both their ages and the ages of other groups of stars.

New research by astrophysicists from the University of Rochester focused on stars in the north part of the constellation, known as Upper Scorpius, which is a part of the Scorpius-Centaurus OB association, one of our best studied groups of young stars and a benchmark sample for investigating the early lives of stars and the evolution of their planet-spawning disks.

The Upper Scorpius stellar group lies roughly 470 light years from Earth.

While those stars have been thought to be just five million years old, the team concludes that those stars are actually more than twice as old, at 11 million years of age. The findings are surprising given Upper Scorpius's status as one of the best-studied samples of young stars in the sky.

The findings by graduate student Mark Pecaut and Assistant Professor Eric Mamajek of Rochester, and Assistant Professor Eric Bubar of Marymount University, were accepted for publication in the Astrophysical Journal.

The scientists came to their conclusions after analyzing hundreds of optical spectra measured with the SMARTS 1.5-meter telescope at Cerro Tololo Inter-American Observatory (CTIO) in Chile, as well as reanalyzing previously published data on the stars.

"We combined our new estimates for the temperatures of the stars based on our spectra, with data on the brightnesses and distances to estimate accurate luminosities," said Pecaut. "Then we used state-of-the-art stellar evolution models to determine the ages."

The Scorpius OB association is a loose group of stars. This group contains many hot, extremely luminous OB-type stars. It is the site of recent star formation.

The stars in such groups are mostly not gravitationally bound but are expanding away from some common center, which presumably marks their birthplace. 

A recent study indicates that the Scorpius association has had 20 supernova explosions over the past 11 million years.

While similar methods were used in the past to calculate ages for some of the Upper Scorpius stars, Pecaut says no previous study has determined independent age estimates for members of the group over such a wide range of stellar masses.

The new analysis shows that stars over a wide range of masses in Upper Scorpius - from slightly more massive than our Sun, up to the mass of the bright star Antares (17 times the mass of our Sun) are giving ages consistent with a mean age of 11 million years.

"For one thing, the distances to the stars are now much more accurately known," said Pecaut. "Also, the newer computer models take into account the rotation of the stars and its effect on the mixing on the star's hydrogen - its nuclear fuel source."

"The first criticism that we heard of the work was that our age estimates for the stars more massive than the Sun in Upper Scorpius disagreed drastically with previously published ages for the smaller stars in the group," said Mamajek.

"However, we think the stellar parameters and models are on much firmer footing for the higher mass stars than for the lowest mass stars.

"The computer models of stars have trouble predicting the correct masses of low-mass stars when they are dynamically measureable, as well as the rate at which the low-mass stars consume their lithium through nuclear reactions.

Hubble and Spitzer Telescopes discover star factory

A star factory from the dawn of time has been discovered that is churning out new suns at the rate of 100 a year.

It has taken 12.9 billion years for light from the blob-shaped galaxy GN-108036 to reach the Earth. When the light began its journey, the universe was only 750 million years old.

Data from the Spitzer and Hubble space telescopes revealed a star production rate within GN-108036 equivalent to around 100 suns per year.

In contrast, our own Milky Way galaxy which is five time larger and 100 times more massive produces 30 times fewer stars.

"The discovery is surprising because previous surveys had not found galaxies this bright so early in the history of the universe," said Dr Mark Dickinson from the National Optical Astronomy Observatory in Tucson, Arizona, US.

"It may be a special, rare object that we just happened to catch during an extreme burst of star formation."

Its great distance was carefully measured from the "redshift" stretching of light to longer red wavelengths by the expansion of the universe.

Objects with larger redshifts are more distant and seen further back in time.

Astronomers first identified the remote galaxy after scanning a large patch of sky with the Subaru Telescope on Mauna Kea, Hawaii.

Only a handful of galaxies have confirmed redshifts greater than seven. GN-108036 has a redshift of 7.2.

ESA ESO VLT: Newborn Massive Stars Dwarf Full-Grown Stellar Giants

Artist’s impression illustrating the formation process of massive stars. 

At the end of the formation process, the surrounding accretion disk disappears, revealing the surface of the young star. 

At this phase the young massive star is much larger than when it has reached a stable equilibrium.

CREDIT: Lucas Ellerbroek/Lex Kaper University of Amsterdam

Massive stars generally start out life much bigger than they will be in maturity, a new study seems to confirm.

Astronomers from the University of Amsterdam got a rare look at a massive star in the process of forming and found that the star will contract until it has reached a stable equilibrium.

The researchers studied the young star B275, which lies in the Omega Nebula, also called the Swan Nebula or Messier 17. This hotbed of gas, dust and young stars lies approximately 5,500 light-years from Earth, in the direction of the Sagittarius constellation.

Astronomers typically struggle to obtain clear observations of a massive star as it is forming, since newborn stars are deeply embedded and obscured in their parent clouds of gas and dust.

Peering through the haze
To lift the veil on the process of star formation, the researchers sifted through ultraviolet and infrared data collected from a powerful spectrograph instrument, called the X-shooter, on the European Space Agency's Very Large Telescope at the Paranal Observatory in Chile.

"The large-wavelength coverage of X-shooter provides the opportunity to determine many stellar properties at once, like the surface temperature, size, and the presence of a disk," study lead author Bram Ochsendorf said in a statement.

Ochsendorf analyzed the data as part of his master's research project at the University of Amsterdam.

The results indicate that B275 is about three times larger than stars that are about seven times more massive than our sun and have reached the so-called main sequence phase of their lives.

The main sequence phase represents a specific stage of stellar evolution in which a star burns hydrogen into helium. (Our own sun is currently in its main sequence.)

The team's findings appear to confirm a theory of star formation predicting that a newly formed massive star will contract until it reaches a more stable state.

NASA: Infra red Image of Cygnus X

This NASA image shows Cygnus X as it hosts many young stellar groupings. 

The combined outflows and ultraviolet radiation from the region's numerous massive stars have heated and pushed gas away from the clusters, producing cavities of hot, lower-density gas. 

In this 8-micron infrared image, ridges of denser gas mark the boundaries of the cavities. 

Bright spots within these ridges show where stars are forming today.

Picture: NASA/PAC/MSX/AFP/Getty

Carl Sagan inspired Art

When she lost her friend Cathy to cancer, artist Michele Banks set out to tell her friend’s story in the language she speaks most fluently and eloquently: painting. But she didn’t want it to be another “cancer painting.”

Instead, she found unlikely inspiration at the intersection of the deadly disease and Carl Sagan’s iconic, life-affirming idea that we’re all made of “star stuff” — she saw a striking parallel between supernovas and dividing cancer cells. The result is simply breathtaking.

I was reading about astronomer Carl Sagan, who often expressed the idea that humans are made of “star stuff”. That is, that all the basic elements of life on earth derive from “space debris” from the gigantic explosions of massive, ancient stars. This concept is at once so simple and so mind-boggling that it’s a struggle to absorb, much less to express artistically. I started looking around for ideas of how to visually portray the basic elements such as hydrogen, helium and nitrogen. Um. This is difficult, because you can’t see them. If you do a Google image search on Carbon, it comes up with a lot of gray-black cars. But when I thought about how the elements were released, I found supernovas. Not only are supernovas beautiful and awe-inspiring, they bear a strong resemblance to dividing cells, especially explosively dividing cancer cells.” ~ Michele Banks

Curiously, Sagan himself also had myelodysplastic syndrome, or “preleukemia,” and underwent three bone marrow transplants before losing the long and difficult fight in 1996. Banks reflects:

This painting, besides celebrating the cosmic connection that all living creatures share, goes out to Cathy and Carl. From the infinitely tiny cells deep in the marrow of their bones, to the billions of stars in the sky.”

You can find Banks on Twitter and her beautiful prints on Etsy.

NASA Hubble: CANDELS in Space

Using its near-infrared vision to peer 9 billion years back in time, NASA's Hubble Space Telescope has uncovered an extraordinary population of young dwarf galaxies brimming with star formation.

While dwarf galaxies are the most common type of galaxy in the universe, the rapid star-birth observed in these newly found examples may force astronomers to reassess their understanding of the ways in which galaxies form.

The galaxies are a hundred times less massive, on average, than the Milky Way, yet churn out stars at such a furious pace that their stellar content would double in just 10 million years. By comparison, the Milky Way would take a thousand times longer to double its star population.

The universe is estimated to be 13.7 billion years old, and these newly discovered galaxies are extreme even for the young universe, when most galaxies were forming stars at higher rates than they are today.

Astronomers using Hubble's instruments could spot the galaxies because the radiation from young, hot stars has caused the oxygen in the gas surrounding them to light up like a bright neon sign.

"The galaxies have been there all along, but up until recently astronomers have been able only to survey tiny patches of sky at the sensitivities necessary to detect them," said Arjen van der Wel of the Max Planck Institute for Astronomy in Heidelberg, Germany, lead author of a paper on the results being published online on Nov. 14 in The Astrophysical Journal.

"We weren't looking specifically for these galaxies, but they stood out because of their unusual colours."

CANDELS
The observations were part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), an ambitious three-year study to analyse the most distant galaxies in the universe. CANDELS is the first census of dwarf galaxies at such an early epoch.

Read the full article here on the Nasa Hubble website

NASA's Hubble Observes Young Dwarf Galaxies Bursting With Stars

This image reveals 18 tiny galaxies uncovered by NASA's Hubble Space Telescope. 

The puny galaxies, shown in the postage stamp-sized images, existed 9 billion years ago and are brimming with star birth. 

Hubble's Wide Field Camera 3 and Advanced Camera for Surveys spied the galaxies in a field called the Great Observatories Origins Deep Survey (GOODS). 

The galaxies are among 69 dwarf galaxies found in the GOODS (marked by green circles in the large image) and other fields.

Images of the individual galaxies were taken November 2010 to January 2011.
 

The large image was taken between Sept. 2002 and Dec. 2004, and between Sept. 2009 and Oct. 2009. 

(Credit: NASA, ESA, A. van der Wel (Max Planck Institute for Astronomy, Heidelberg, Germany), H. Ferguson and A. Koekemoer (STScI.), and the CANDELS team)