September 19, 2012
Spitzer And Hubble Telescopes Discover Furthest Galaxy Ever
Lee Rannals for redOrbit.com — Your Universe Online
A long time ago, in a galaxy far, far away, light took off, then traveled 13.2 billion light-years until it was finally picked up by NASA's telescopes.
Astronomers have identified the furthest galaxy ever using NASA's Spitzer and Hubble space telescopes.
The light captured by the telescope was from when the universe was just 500 million years old, according to NASA.
"This galaxy is the most distant object we have ever observed with high confidence," 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, said in a statement. "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 galaxy travelled about 13.2 billion light-years before finally reaching the Earth, a time in which the universe was just 3.6% of its present age.
Objects that lie at these great distances are mostly beyond the detection sensitivity of the largest telescopes, so astronomers have to rely on gravitational lensing in order to capture them.
This technique, which was first predicted by Albert Einstein, is when the gravity of foreground objects warps and magnifies the light from background objects.
NASA said that based on the Hubble and Spitzer observations, astronomers believe the distant galaxy was less than 200 million years old when it was viewed.
The galaxy contains only about one percent of the Milky Way's mass, which also coincides with theories that the first galaxies in the universe started out very tiny.
These galaxies played the dominant role in the epoch of reionization, the event that began the demise of the universe's dark ages. This event lasted about 400,000 years after the Big Bang, when neutral hydrogen gas formed from cooling particles.
"In essence, during the epoch of reionization, the lights came on in the universe," paper co-author Leonidas Moustakas, a research scientist at NASA's Jet Propulsion Laboratory, said in a statement.