Composite image of the galaxy cluster which helped reveal the newly discovered galaxy – MACS0647-JD. The inset at left shows a close up of the young dwarf galaxy. (NASA)

Scientists have discovered what could be the oldest, most distant galaxy in the universe, thanks to a unique combination of man-made and natural telescopes.

The newly discovered galaxy, MACS0647-JD, was found by the Cluster Lensing And Supernova Survey with Hubble (CLASH).

It is about 13.3 billion light years, or 125,825,000,000,000,000,000,000 km, from Earth. Scientists are getting to see it just as it was 420 million years after the Big Bang, or when the universe was only three percent of its current age of about 13.7 billion years.

Astronomers made the discovery by combining the power of the Hubble Space Telescope, the Spitzer Space Telescope and a natural zoom effect called gravitational lensing, which uses enormous galaxy clusters as interstellar telescopes to magnify distant galaxies behind them.

The effect is achieved when the light rays from the distant object are bent by the gravity of the huge galaxy clusters, just like a giant cosmic lens, that lie between the object and  Earth.

“While one occasionally expects to find an extremely distant galaxy using the tremendous power of gravitational lensing, this latest discovery has outstripped even my expectations of what would be possible with the CLASH program,” said Rychard Bouwens of Leiden University in the Netherlands, a co-author of the study that outlined the discovery. “The science output in this regard has been incredible.”

The massive galaxy cluster that’s making the distant galaxy appear brighter than it normally would, providing the natural boost to the Hubble and Spitzer telescopes, , is called MACS J0647.7+7015 and is about five billion light years away.

Hubble in orbit above the Earth (Photo: NASA)

Because of the gravitational lensing provided by the cluster, the CLASH team was able to observe three magnified images of MACS0647-JD with the Hubble.

“This cluster does what no man-made telescope can do,” said Marc Postman of the Space Telescope Science Institute, who leads the CLASH team. “Without the magnification, it would require a Herculean effort to observe this galaxy.”

The astronomers say that the distant galaxy is so small, about 600 light years across according to their observations that it may be going through its first stages formation. Our own Milky Way galaxy is about 150,000 light years across.

“This object may be one of many building blocks of a galaxy,” says Dan Coe from the Space Telescope Institute and lead author of the study.  “Over the next 13 billion years, it may have dozens, hundreds, or even thousands of merging events with other galaxies and galaxy fragments.”

The galaxy could turn out to be too far away for astronomers to confirm its distance with any of the current available technology.  But once the new James Webb Space Telescope launches in 2018, astronomers expect to be able to take a definitive measurement of its distance and to study the properties of the galaxy in more detail.

MACS0647-JD, is very young and only a tiny fraction of the size of our Milky Way. The object is observed 420 million years after the big bang.   (Video: NASA, ESA, and G. Bacon (STScI))

The farthest-ever view of the universe. Hubble’s “extreme Deep Field (XDF) is a composite made from 2,000 images, taken by the Hubble Space Telescope over a 10 year period. (Credit: NASA; ESA; G. Illingworth, D. Magee, and P. Oesch, University of California, Santa Cruz; R. Bouwens, Leiden University; and the HUDF09 Team)

The Hubble Space Telescope has given us  the deepest view of space ever.

Called the eXtreme Deep Field, or XDF, it’s a composite of more than 2,000 photos taken by Hubble over 10 years.

“The XDF is the deepest image of the sky ever obtained and reveals the faintest and most distant galaxies ever seen. XDF allows us to explore further back in time than ever before,” said Garth Illingworth of the University of California at Santa Cruz, principal investigator of the Hubble Ultra Deep Field 2009 (HUDF09) program.

Hubble’s Advanced Camera for Surveys and its Wide Field Camera 3 focused on a tiny spot of the southern sky, which was found in the center of the original Hubble Ultra Deep Field (UDF), a composite created from Hubble Space Telescope data gathered from 2003 and 2004.

While the images that made up the UDF revealed thousands of near and very distant galaxies, the newly released full-color XDF image reaches much fainter galaxies.  NASA scientists say the new XDF also contains about 5,500 galaxies which were taken within a smaller field of view than the UDF.

In creating the XDF,  astronomers were able to use very deep exposures in red light  taken by Hubble’s new infrared camera, which was installed by the Space Shuttle Atlantis in 2009. The data and images taken by the new camera will allow astronomers to study some of the earliest galaxies in the universe. The faintest galaxies in the XDF are one ten-billionth the brightness of what the human eye can see, according to NASA.

This illustration separates the XDF into three planes showing foreground, background, and very far background galaxies. These divisions reflect different epochs in the evolving universe. (Image: NASA, ESA, and Z. Levay, F. Summers (STScI))

The XDF not only provides a unique view of some of the deepest recesses of space but  also serves as a “time tunnel into the distant past.”

The universe is believed to be 13.7 billion years old, and the XDF shows galaxies that go back some 13.2 billion years, less than 500 million years after the Big Bang. The youngest galaxy found in the XDF existed just 450 million years after the birth of the universe.

The XDF will give astronomers the opportunity to view and study those ancient galaxies when they were young, small and growing.

If you would like to learn more about the eXtreme Deep Field, the Space Telescope Science Institute (STScI), which operates the science program for the Hubble Space Telescope, is inviting the public to an online seminar  Thursday, September 27, at 1700 UTC.

Three  astronomers from the XDF observing team will describe how they assembled the spectacular image and explain what it tells us about the evolving universe.  Participants can send in questions for the panel of experts. To participate, visit hubblesite.org.

This video explains how astronomers meticulously assembled mankind’s deepest view of the universe from combining Hubble Space Telescope exposures taken over the past decade. Guest scientists are Dr. Garth Illingworth and Dr. Marc Postman.  (Video: NASA, ESA, and M. Estacion and G. Bacon (STScI))

(Photo: NASA, M.Masetti)

If you think you have what it takes to build a satellite, NASA has just introduced an online game that might appeal to you.

With “Build It Yourself: Satellite!” the US space agency offers users the chance to act as engineers and astronomers who conceive and build their own special virtual satellite.

“It’s fun to play,” says Maggie Masetti, a NASA webmaster who created the game. “And users will learn something about satellite instrumentation and optics and how they are used to make scientific discoveries, as well about a large range of different existing astronomical missions.”

The game lets players choose what kind of science their satellite will study. They can then customize the sophisticated technical aspects of their satellite – such as what wavelengths their creation will operate at and what kind of tools, instruments and optics will give them the best opportunity to learn as much as possible about their chosen science.

Artist conception of James Webb Space Telescope (Image: NASA)

A number of astronomical missions, some dating back to 1980s, are available to game players.  You can go from rather small x-ray telescopes, like NASA’s Rossi X-ray Timing Explorer, to the much larger and popular  Hubble Space Telescope.

The game is available in two sizes so players can choose the one better suited to their monitor.  If you’re stuck with a slower computer, the game offers a special toggle button that will reduce the quality of the graphics but will make the game run faster.

The new gaming experience was inspired by the James Webb space telescope, which is being built now and is scheduled for launch in 2018.

Said to have the latest cutting-edge technology, the Webb space telescope will help scientists expose the secrets of the universe by taking them far back in time, toward the Big Bang.  Webb will be the most powerful telescope ever built by the space agency.

Who knows, maybe after playing “Build It Yourself: Satellite!” you’ll realize you have the talent and ability to become a real-life rocket scientist!

Time-lapse of the construction of the giant structural steel frame that will be used to assemble the mirrors and instruments of the James Webb Space Telescope.

NASA finds there are more potentially hazardous asteroids (PHA)s, closely aligned with the plane of our solar system than previous models suggested. (Image: NASA/JPL-Caltech)

First, the good news. There are fewer asteroids near Earth than previously estimated.  Now the bad news. A new NASA survey also finds there may be more than twice as many aligned with Earth’s orbit than thought, which could increase the odds of an asteroid coming close enough to us to cause concern.

The findings from NASA/JPL’s Near Earth Object Wide-field Infrared Explorer (NEOWISE) project also reveal new information about the origins and possible dangers these space objects might pose.

Potentially hazardous asteroids, or PHA’s, are a subset of a larger group of near-Earth asteroids,  which come within eight million kilometers of us and are big enough to pass through Earth’s atmosphere, causing a great amount of damage.

To get a count on how many of these possible troublemakers are out there, NASA used one of its space telescopes to make an assessment of our solar system’s population of PHA’s.

WISE, an unmanned satellite carrying an infrared heat-sensitive telescope, was launched in December 2009 and spent a little over a year imaging the entire sky to provide data on asteroids, the coolest and dimmest stars, and the most radiant galaxies.

Approximately 4,700 PHAs, give or take about 1,500, with diameters larger than 100 meters, were found, according to NEOWISE principal investigator Amy Mainzer.

Most of the asteroids in our solar system never get close to Earth.  They’re found in what’s called the Asteroid Belt, which is between the orbits of Mars and Jupiter.

Scientists think these asteroids may have been fragments that were trying to come together to form a planet when the solar system was forming.  However,  the overwhelming gravitational influence of Jupiter was so strong, it kept the planet from forming.

But, occasionally, if there is an interaction with one of the giant planets, some of the asteroids may be forced to wander away from the main belt and into near-Earth space – causing concern for those of here on terra firma.

To make their tally, Mainzer along with her colleagues at JPL examined approximately 107 PHA’s with WISE telescope data, providing them with a representative sample of the total population of these potentially dangerous objects.

From that sample, Mainzer’s team was able to calculate the total number of PHA’s in the solar system.

This diagram illustrates the differences between orbits of a typical near-Earth asteroid (blue) and a potentially hazardous asteroid (PHA) (orange). (Image: NASA/JPL-Caltech)

Of course, the big question remains how likely is it that one of these potentially-hazardous asteroids actually could strike Earth.   Mainzer, looking back at Earth’s history, points out that major asteroid strikes very rarely happen.  Scientists estimate that such a major hit happens every 100 million years or so.  The last mammoth asteroid collided with Earth about 65 million years ago, causing, scientists think, the extinction of most life on our planet, including the dinosaurs.

Mainzer says astronomers have already discovered most of the significant asteroids out there.  However, she warns, there are many smaller asteroids, which haven’t been discovered yet.  The NEOWISE study indicates that only between 20 and 30 percent of these have been discovered so far.

To keep us safer from asteroid impacts, Mainzer says the most important thing that we can do is actually go look for them.  “Because, if you don’t know where they are, you have no idea how to really deal with any risk,” she says.

Mainzer and her colleagues are currently working on a proposal to build and carry out an advanced survey mission.  Called the Near Earth Object Camera (NEOCam), this proposed mission would locate many more asteroids to provide a more accurate picture of the total asteroid population.

Dr. Amy Mainzer joins us on this week’s radio edition of Science World.  Check out the right column for scheduled air-times or listen to the interview with Dr. Mainzer below.

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Other stories we cover on the “Science World” radio program this week include:

• Success! Privately-funded cargo spacecraft docks with the ISS
• Recommendation to halt prostate cancer screening stirs controversy
• Scientists, lawmakers target invasive Asian fish species
• Babies born by C-section more likely to become obese, study says