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Far-Off Galaxy Opens Window on Dawn of the of Universe




Astronomers have spotted what could be the most distant galaxy ever seen. Light from the young galaxy captured by the orbiting Spitzer and Hubbleobservatories first shone when our 13.7-billion-year-old universe was just 500 million years old.

The far-off galaxy existed within an important era when the universe began to transit from the so-called cosmic dark ages. During this period, the universe went from a dark, starless expanse to a recognizable cosmos full of galaxies. The discovery of the faint, small galaxy opens a window onto the deepest, most remote epochs of cosmic history.

"This galaxy is the most distant object we have ever observed with high confidence," said Wei Zheng, a principal research scientist in the department of physics and astronomy at Johns Hopkins University in Baltimore who is lead author of a new paper appearing in Nature. "Future work involving this galaxy, as well as others like it that we hope to find, will allow us to study the universe's earliest objects and how the dark ages ended."

Light from the primordial galaxy traveled approximately 13.2 billion light-years before reaching NASA's telescopes. In other words, the starlight snagged by Hubble and Spitzer left the galaxy when the universe was just 3.6 percent of its present age. Technically speaking, the galaxy has a redshift, or "z," of 9.6. The term redshift refers to how much an object's light has shifted into longer wavelengths as a result of the expansion of the universe. Astronomers use redshift to describe cosmic distances.

Unlike previous detections of galaxy candidates in this age range, which were only glimpsed in a single color, or waveband, this newfound galaxy has been seen in five different wavebands. As part of the Cluster Lensing And Supernova Survey with Hubble Program, the Hubble Space Telescope registered the newly described, far-flung galaxy in four visible and infrared wavelength bands. Spitzer measured it in a fifth, longer-wavelength infrared band, placing the discovery on firmer ground.

Objects at these extreme distances are mostly beyond the detection sensitivity of today's largest telescopes. To catch sight of these early, distant galaxies, astronomers rely on gravitational lensing. In this phenomenon, predicted by Albert Einstein a century ago, the gravity of foreground objects warps and magnifies the light from background objects. A massive galaxy cluster situated between our galaxy and the newfound galaxy magnified the newfound galaxy's light, brightening the remote object some 15 times and bringing it into view.

Based on the Hubble and Spitzer observations, astronomers think the distant galaxy was less than 200 million years old when it was viewed. It also is small and compact, containing only about 1 percent of the Milky Way's mass. According to leading cosmological theories, the first galaxies indeed should have started out tiny. They then progressively merged, eventually accumulating into the sizable galaxies of the more modern universe. *These first galaxies likely played the dominant role in the epoch of reionization, the event that signaled the demise of the universe's dark ages. This epoch began about 400,000 years after the Big Bang when neutral hydrogen gas formed from cooling particles. The first luminous stars and their host galaxies emerged a few hundred million years later. The energy released by these earliest galaxies is thought to have caused the neutral hydrogen strewn throughout the universe to ionize, or lose an electron, a state that the gas has remained in since that time.

"In essence, during the epoch of reionization, the lights came on in the universe," said paper co-author Leonidas Moustakas, a research scientist at NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif.

Astronomers plan to study the rise of the first stars and galaxies and the epoch of reionization with the successor to both Hubble and Spitzer, NASA's James Webb Telescope, which is scheduled for launch in 2018. The newly described distant galaxy will likely be a prime target.




The Daily Galaxy via 

Image credit: NASA/ESA/STScI/JHU


The scientists and govt. all over the world, should look for another planet that the next generations to come to be living in. In case, sadly, Earth is no longer livable/habitable.

I wonder what people will think when/if we find a galaxy 14 bly away.

Q, sadly we can’t go there in a matter of hours, days or weeks like here on Earth. We aren’t that capable yet to actually say for certain what these things are on another planet on a very far away galaxy. Because arent actually there. I have birth deffects, I would love to go to a planet where they can fix my problems w/c needs multiple operations not to mention complicated, in a matter of seconds or minutes. I can dream right?

Hi Mary Anne... You should not be disheartened, where there's life there's always hope. I hope for a miracle for you.

And so to the problem of us humans having a need to spread out into the Universe: There are no buses! I'm beginning to think we may first terraform Mars, with the help of asteroids from the asteroid belt, so may not have to travel too far until technology allows us to skip between dimensions. On a cosmic scale, Mars is mere walking distance!

I hope this message gives you hope, for your future and that of all mankind.

I think you missed my point Mary Ann. What I was getting at is that the article is talking about the most distant galaxy seen thus far is 13.2 billion light years away and the estimated age of our universe is 13.7 billion light years. So if we find a galaxy that's 14 billion light years away scientists will be scrambling to explain that one.

This is utterly spectacular!

Q, I don't see it as Mary Ann missing your point, and instead see it as Mary Ann making her own points, even if they're somewhat unrelated to the details of the article.

I often feel like Mary Ann does and wish that I could go to another planet where things are better, if there is such a place. We humans are rapidly destroying our Earthly home, and I suspect that many people dream of going to a better place. Who knows, maybe someday such a planet will be found and may be reachable.

I find the subject of the article to be fascinating, and I'm very anxious to see what the James Webb Telescope is able to discover after it's launched. I wish they would hurry up and get that thing into space. :)

By the way Q, your question about finding a galaxy galaxy 14 bly away is interesting. I wouldn't be surprised if some galaxies are eventually found that are that far away and much more. The universe may be bigger and older than is currently posited.

Mary Anne,
And how would we get to this new planet when Humankind can barley crawl of this one. Maybe you should think before you type.

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