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New images by the Huuble and Spitzer space observatories show the farthest galaxy ever recorded as a diminutive blob that is only a tiny fraction of the size of our Milky Way galaxy. But it offers a peek back into a time when the universe was three percent of its present age of 13.7 billion years. The newly discovered galaxy, named MACS0647-JD, was observed 420 million years after the big bang, the theorized beginning of the universe. Its light has traveled 13.3 billion years to reach Earth.

This find is the latest discovery from a program that uses natural zoom lenses to reveal distant galaxies in the early universe. The Cluster Lensing And Supernova Survey with Hubble (CLASH), an international group led by Marc Postman of the Space Telescope Science Institute in Baltimore, is using massive galaxy clusters as cosmic telescopes to magnify distant galaxies behind them. This effect is called gravitational lensing.

Along the way, 8 billion years into its journey, light from MACS0647-JD took a detour along multiple paths around the massive galaxy cluster MACS J0647+7015 (image above). Without the cluster's magnification powers, astronomers would not have seen this remote galaxy. Because of gravitational lensing, the CLASH research team was able to observe three magnified images of MACS0647-JD with the Hubble telescope. The cluster's gravity boosted the light from the faraway galaxy, making the images appear about eight, seven, and two times brighter than they otherwise would, enabling astronomers to detect the galaxy more efficiently and with greater confidence. * "This cluster does what no man-made telescope can do," said Postman. "Without the magnification, it would require a Herculean effort to observe this galaxy."

ACS0647-JD is so small it may be in the first steps of forming a larger galaxy. An analysis shows the galaxy is less than 600 light-years wide. Based on observations of somewhat closer galaxies, astronomers estimate that a typical galaxy of a similar age should be about 2,000 light-years wide. For comparison, the Large Magellanic Cloud, a dwarf galaxy companion to the Milky Way, is 14,000 light-years wide. Our Milky Way is 150,000 light-years across.

"This object may be one of many building blocks of a galaxy," said the study's lead author, Dan Coe of the Space Telescope Science Institute. "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 was observed with 17 filters, spanning near-ultraviolet to near-infrared wavelengths, using Hubble's Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS). Coe, a CLASH team member, discovered the galaxy in February while poring over a catalogue of thousands of gravitationally lensed objects found in Hubble observations of 17 clusters in the CLASH survey. But the galaxy appeared only in the two reddest filters.

"So either MACS0647-JD is a very red object, only shining at red wavelengths, or it is extremely distant and its light has been 'redshifted' to these wavelengths, or some combination of the two," Coe said. "We considered this full range of possibilities."

Redshift is a consequence of the expansion of space over cosmic time. Astronomers study the distant universe in near-infrared light because the expansion of space stretches ultraviolet and visible light from galaxies into infrared wavelengths. Coe estimates MACS0647-JD has a redshift of 11, the highest yet observed.

The CLASH team identified multiple images of eight galaxies lensed by the galaxy cluster. Their positions allowed the team to produce a map of the cluster's mass, which is primarily composed of dark matter. Dark matter is an invisible form of matter that makes up the bulk of the universe's mass.

"It's like a big puzzle," said Coe. "We have to arrange the mass in the cluster so that it deflects the light of each galaxy to the positions observed." The team's analysis revealed that the cluster's mass distribution produced three lensed images of MACS0647-JD at the positions and relative brightness observed in the Hubble image.

Coe and his collaborators spent months systematically ruling out these other alternative explanations for the object's identity, including red stars, brown dwarfs and red (old or dusty) galaxies at intermediate distances from Earth. They concluded that a very distant galaxy was the correct explanation.

Images of the galaxy at longer wavelengths obtained with the Spitzer Space Telescope played a key role in the analysis. If the object were intrinsically red, it would appear bright in the Spitzer images. Instead, the galaxy barely was detected, if at all, indicating its great distance. The research team plans to use Spitzer to obtain deeper observations of the galaxy, which should yield confident detections as well as estimates of the object's age and dust content. MACS0647-JD galaxy, however, may be too far away for any current telescope to confirm the distance based on spectroscopy, which spreads out an object's light into thousands of colors.

Nevertheless, Coe is confident the fledgling galaxy is the new distance champion based on its unique colors and the research team's extensive analysis. "All three of the lensed galaxy images match fairly well and are in positions you would expect for a galaxy at that remote distance when you look at the predictions from our best lens models for this cluster," Coe said.

The new distance champion is the second remote galaxy uncovered in the CLASH survey, a multi-wavelength census of 25 hefty galaxy clusters with Hubble's ACS and WFC3. Earlier this year, the CLASH team announced the discovery of a galaxy that existed when the universe was 490 million years old, 70 million years later than the new record-breaking galaxy.

So far, the survey has completed observations for 20 of the 25 clusters. The team hopes to use Hubble to search for more dwarf galaxies at these early epochs. If these infant galaxies are numerous, then they could have provided the energy to burn off the fog of hydrogen that blanketed the universe, a process called re-ionization. Re-ionization ultimately made the universe transparent to light.


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The Daily Galaxy via NASA/JPL


I just thought of something, there is a current debate about the true age of the universe. With the excepted age being around 13.7 billion years old. However we also know that light can be bent and distorted by gravity, as the universe is basically full of objects that have mass (gravity). So could the light we are seeing be so distorted by super massive black holes and the big bang event itself somehow, so that the light we are seeing cannot be considered a true image of space?

If by Universe you mean the whole of existence, than it doesn't make any sense to ask of its age, because existence is eternal.

And the Big Bang cosmology is just a religion. Unfalsifiable claims, ad hoc assumptions, etc. - this just isn't science anymore. Besides, cosmology is not a science to begin with, it is a philosophical endeavor.

Because of the extremem distance involved, Bell Telephone says that if you want to phone there, the rates would be "astronomical!"

I find the quote "Redshift is a consequence of the expansion of space over cosmic time" interesting. I never thought of it like that. I thought red shift (and it is) is a lengthening of the "wave" we call it, of photons as their propigator moves away from the observer. I guess expansion of space would have the same effect of lengthening the "wave" entity of photons' frequency?

It may help when mankind eventually finds out what light really is and it's "frequency" as well and infinitely it would help to know what the universe really is, where it really came from and where it's headed on its time line. Mankind is at best, hacks. Give us a half million years more to evolve into a more intelligent being and perhaps, just perhaps then, we'd give understanding this universe a better shot.

I do admire hacks. Nicola Tesla, Albert Einstein, Leonardo Divinci are my favorite hacks...those who work with observations and generate theories therefrom, yet not understanding fully the universe which provides the observations and blackboards.

A dog can observe an atomic bomb explosion but can't possibly concept it due to limits in intelligence itself, so the dog merely observes the explosion and that's that. The dog was in the process of observation only. Humankind is in the process of observation only at this stage. We observe with more perception than a dog observes but we still are just observers. We put things together in laboratories and tear apart particles at Cern but we are just observing and not understanding a darned thing.

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