The Absolute Cosmos: Oldest and most distant galaxy found
An international team of scientists recently identified what appears to be the oldest and most distant galaxy ever observed in the Universe.
The galaxy has been named GN-z11 and it lies 13.4 billion light years away from us.
The team was led by Linhua Jiang (from Kavli Institute for Astronomy and Astrophysics) and Prof. Nobunari Kashikawa (from University of Tokyo, Japan).
The team studied the GN-z11’s redshift in order to locate its distance from planet Earth. Generally, the farther the object/body is from Earth, the more redshifted its light will be.
Team also looked at the chemical signatures in the light (emission lines) coming from galaxy GN-z11. These emissions help scientists in calculating the overall distance of galaxy from Earth.
The team specifically looked at ultraviolet light as they expected to find the redshifted chemical signatures in this area of the electromagnetic spectrum. The signatures were detected by Hubble Space Telescope multiple times in GN-z11’s spectrum.
However, even Hubble was not capable of resolving ultraviolet emission lines to the degree needed by scientists. So they used MOSFIRE- a ground based spectrograph, an instrument dedicated to measure emission lines.
By using MOSFIRE, scientists observed and studied GN-z11’s emission lines in detail. If further upcoming observations can confirm the study findings, GN-z11 will certainly become the most distant galaxy ever observed.