A Galaxy Far, Far Away: Hubble Finds Oldest, Most Distant Galaxy Yet

Friday, 04 March 2016 - 11:47AM
Friday, 04 March 2016 - 11:47AM
A Galaxy Far, Far Away: Hubble Finds Oldest, Most Distant Galaxy Yet
NASA's Hubble telescope has just added another major astronomical discovery to its list of accomplishments, as researchers have just discovered the oldest, most distant galaxy ever observed from Earth, or one that came into existence "a long, long time ago" and "far, far away."



The "remarkably luminous" galaxy GN-z11 is 25 times smaller than the Milky Way and has only one percent of our galaxy's mass. However, it is forming new stars at an extremely prolific rate, about 20 times greater than our own galaxy, which makes it bright enough to be spotted by the Hubble telescope. GNz-11 formed 13.4 billion years ago, only 400 million years after the Big Bang, making it a whopping 150 million years older than the previous record holder.

Opening quote
"We've taken a major step back in time, beyond what we'd ever expected to be able to do with Hubble," lead author Pascal Oesch said in a statement. "We managed to look back in time to measure the distance to a galaxy when the Universe was only three percent of its current age."
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In a paper published in Astrophysical Journal, the researchers detail their discovery of this galaxy through spectroscopic analysis, which splits the light of the galaxy into its component colors. They measured the distance by observing the "redshift" of the galaxy, or the extent to which the wavelengths of the emitted light are becoming longer and closer to the red side of the light spectrum. The redshift is directly proportional to the age of the galaxy, since the wavelengths become longer as they travel through space, creating the illusion that faraway objects in the expanding universe are receding from Earth.

GNz-11 has an observed redshift of 11.1, bringing its estimated age 200 million years closer to the Big Bang than the previous record holder, which has a redshift of 8.68, making it approximately 13.2 billion years old. The researchers hope that the James Webb Space Telescope, which is set to be launched in 2018, will break this record, but for now, the discovery of this galaxy gives significant insight into the nature of the early universe.


Opening quote
"It's amazing that a galaxy so massive existed only 200 million to 300 million years after the very first stars started to form," said co-author Garth Illingworth. "It takes really fast growth, producing stars at a huge rate, to have formed a galaxy that is a billion solar masses so soon."
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And, as a bonus, here's a beautiful picture released today by Hubble of a "stellar fingerprint," or the emissions from a young star 2,300 lightyears from Earth:

Stellar Fingerprint from Hubble
Science
NASA

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