Hubble breaks cosmic distance record
By pushing the NASA/ESA Hubble Space Telescope to its limits astronomers have shattered the cosmic distance record by measuring the distance to the most remote galaxy ever seen in the Universe. This galaxy existed just 400 million years after the Big Bang and provides new insights into the first generation of galaxies. This is the first time that the distance of an object so far away has been measured from its spectrum, which makes the measurement extremely reliable. The results will be published in the Astrophysical Journal.
Using the NASA/ESA Hubble Space Telescope an international team of astronomers has measured the distance to this new galaxy, named GN-z11. Although extremely faint, the galaxy is unusually bright considering its distance from Earth. The distance measurement of GN-z11 provides additional strong evidence that other unusually bright galaxies found in earlier Hubble images are really at extraordinary distances, showing that we are closing in on the first galaxies that formed in the Universe.
Previously, astronomers had estimated GN-z11s distance by analysing its colour in images taken with both Hubble and the NASA Spitzer Space Telescope. Now, for the first time for a galaxy at such an extreme distance, the team has used Hubbles Wide Field Camera 3 (WFC3) to precisely measure the distance to GN-z11 spectroscopically by splitting the light into its component colours.
Our spectroscopic observations reveal the galaxy to be even further away than we had originally thought, right at the distance limit of what Hubble can observe, explains Gabriel Brammer of the Space Telescope Science Institute and second author of the study.
This puts GN-z11 at a distance that was once thought only to be reachable with the upcoming NASA/ESA/CSA James Webb Space Telescope (JWST) [1].
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