Caltech researchers discover farthest galaxy ever

Caltech researchers have made an impressive discovery of the most distant galaxy from Earth ever found. The galaxy is called EGS8p7 and is over 13.2 billion years old. Compare that to the estimated age of the universe at about 13.8 billion years old and you can see why the researchers are excited about the find.

The galaxy had been identified as a candidate for more investigation using data gathered by the Hubble and Spitzer space telescopes. The researcher used the multi-object spectrometer for infrared exploration instrument at the W.M. Keck Observatory in Hawaii to perform a spectrographic analysis of the galaxy to determine its redshift.

Redshift is the shift in the actual color of light to redder wavelengths due to Doppler effect. Redshift is normally used to measure distances to galaxies. The scientists say that Redshift is hard to use for the most distant objects, also the earliest objects in the universe because of phenomenon in the early universe that prevented the transmission of light.

With EGS8p7 being formed 380,000 years after the Big Bang, the universe was cool enough that light could travel throughout. The scientists say that before reinoization in the early universe, clouds of neutral hydrogen atoms would have absorbed certain types of radiation emitted by newly forming galaxies, including the Lyman-alpha line. Due to that absorption, in theory it shod have been impossible to observe a Lyman-alpha line from EGS8p7. The team believes that hydrogen reionization may not have occurred in a uniform manner, allowing the Lyman-alpha line to be observed in this case.

SOURCE: Caltech