By pushing the Hubble Space Telescope to its extreme limits astronomers have crushed the cosmic distance record by calculating the distance to the most distant galaxy ever seen in the Cosmos. This galaxy existed just 400 million years after the Big Bang and offers new understandings into the first group of galaxies ever formed in the universe. This is the first time that the distance of an object so distant has been measured from its spectrum, which makes the measurement tremendously dependable. The results are expected to be published in the Astrophysical Journal. Image: NASA/ESA
The illustration above displays a timeline of the Cosmos, extending from the present day (left) back to the Big Bang, 13.8 billion years ago (right) (Image Shown Below). This newly discovered galaxy GN-z11 is the most distant galaxy spotted so far, at a redshift of almost 11.1, which corresponds to 400 million years after the Big Bang.
Before, astronomers had projected GN-z11’s distance by examining its color in images captured with both Hubble and the NASA Spitzer Space Telescope. But now, for the first time for a galaxy at such a great distance, astronomers have used Hubble’s Wide Field Camera 3 (WFC3) to accurately measure the distance to GN-z11 spectroscopically by dividing the light into its component colors.
Gabriel Brammer of the Space Telescope Science Institute and second author of the study, explains “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.”
This puts GN-z11 at a distance that was once believed only to be accessible with the forthcoming NASA/ESA/CSA James Webb Space Telescope (JWST).