Astronomers identify most distant galaxy yet discovered

The galaxy EGS-zs8-1 lies 13.1 billion light-years away, making it the farthest known galaxy yet. 

|
NASA, ESA, P. Oesch and I. Momcheva (Yale University0), and the 3D-HST and HUDF09/XDF teams
The farthest confirmed galaxy to date, EGS-zs8-1, imaged here by the Hubble Space Telescope. New measurements taken at the W. M. Keck Observatory show that the galaxy lies about 13.1 billion light years from Earth.

A galaxy far, far away — farther, in fact, than any other known galaxy — has been measured by astronomers.

The galaxy EGS-zs8-1 lies 13.1 billion light-years from Earth, the largest distance ever measured between Earth and another galaxy.

The universe is thought to be about 13.8 billion years old, so galaxy EGS-zs8-1 is also one of the earliest galaxies to form in the cosmos. Further studies could provide a glimpse at how these early galaxies helped produce the heavy elements that are essential for building the diversity of life and landscapes we see on Earth today. [The Greatest Galaxy Images Ever Taken]

EGS-zs8-1 is one of the brightest objects observed in this region, which is around 13 billion light-years from Earth. The authors of the new research say other galaxies likely lie at similar distances or even further from Earth, but they are too faint for scientists to measure their exact distance.

"We have a lot of sources that we can see with Hubble that are probably farther way" than EGS-zs8-1, said Pascal Oesch, a postdoctoral researcher at Yale and lead author of the new study. "But we cannot measure their exact distance yet."

To measure the separation between Earth and a far-off cosmic object, astronomers often look at how quickly those objects are moving away from Earth. The universe is expanding; space itself is growing like a balloon or a loaf of bread in the oven. Objects in the universe thus move away from each other, like raisins in the bread dough.

As these objects move away from Earth, the light they emit becomes shifted. The more far-flung an object is, the faster it appears to move away from Earth, and the more the light is shifted. So, by measuring the degree of shifting — known as "redshift" — astronomers can also measure distance. A higher redshift equals a larger distance, and galaxy EGS-zs8-1 has the highest redshift ever measured, according to the new research (the previous record holder has a redshift that is only slightly smaller).

Galaxy EGS-zs8-1 was originally identified by the Hubble Space Telescope and the infrared Spitzer Space Telescope, and stood out because of the unique colors it emitted. The new research used observations conducted with the MOSFIRE instrument on the W.M. Keck Observatory's 10-meter (33 feet) telescope in Hawaii.

The light from EGS has traveled a distance of 13.1 billion light-years, so the light shows EGS-zs8-1 as it was 13.1 billion years ago. At that time, the universe was only about 670 million years old, or about 5 percent itscurrent age of about 13.8 billion years, according to a statement from Yale. The first stars began forming about 200 million to 300 million years after the Big Bang, according to Oesch.

By combining observations from Keck, Spitzer and Hubble, the researchers say they can estimate that the stars in EGS-zs8-1 are "between 100 [million] and 300 million years old." But Oesch said it is difficult to know how old EGS-zs8-1 is compared to other galaxies at a similar distance from Earth. It is, however, one of the oldest galaxies yet measured.

The new observations also show that EGS-zs8-1 is forming stars 80 times faster than the Milky Way. In addition, the still-growing galaxy has "already built more than 15 percent of the mass of our own Milky Way today," Oesch said in a statement from Yale University.

The unique colors observed in EGS and other early galaxies by the Spitzer Space Telescope present questions about what took place in these primeval environments. According to the statement, these colors could have been caused by the rapid formation of massive, young stars that interacted with the primordial gas in these galaxies. Oesch said further study of the galaxy could reveal the types and amounts of heavy elements that formed there.

"By looking at different galaxies as a function of time, we can reconstruct the build-up of the heavy elements that we see around us today and that we're all made of," Oesch said. In addition, the new observations provide "an indication of how the stars were forming at these extreme distances, and they seem to be forming differently than the local universe. Every discovery opens up a whole new set of questions."

The research appeared online today (May 5) in the journal Astrophysical Journal Letters. A pre-print of the paper can be found online. .

Follow Calla Cofield @callacofieldFollow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

Copyright 2015 SPACE.com, a Purch company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

You've read  of  free articles. Subscribe to continue.
Real news can be honest, hopeful, credible, constructive.
What is the Monitor difference? Tackling the tough headlines – with humanity. Listening to sources – with respect. Seeing the story that others are missing by reporting what so often gets overlooked: the values that connect us. That’s Monitor reporting – news that changes how you see the world.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to CSMonitor.com.

QR Code to Astronomers identify most distant galaxy yet discovered
Read this article in
https://www.csmonitor.com/Science/2015/0506/Astronomers-identify-most-distant-galaxy-yet-discovered
QR Code to Subscription page
Start your subscription today
https://www.csmonitor.com/subscribe