After pushing NASA/ESA’s Hubble Space Telescope to its limits, a group of astronomers at the Space Telescope Science Institute (STScI) and Yale University were able to take a glimpse at the farthest galaxy to date. The space observatory found galaxy GN-z11 while it was gazing in the direction of Ursa Major constellation.
Researchers estimate that the newly found object is located 13.4 billion light years from Earth, which means that it is from the universe’s earliest days. Astronomer Pascal Oesch, one of the leaders of the team that made the discovery, explained that the galaxy is from a time when the universe was 3% of its age.
Oesch added that his team was surprised to achieve the feat with the 25-year-old Hubble. Currently, astronomers plan to detect space objects located at such enormous distances with NASA’s $8.7 billion James Webb Space Telescope, which is in the making.
Astronomers realized that some photos taken by Hubble over the years may show unusually bright galaxies that are located at incredibly great distances. Scientists could calculate GN-z11’s location by analyzing its color in Hubble’s and Spitzer Space Telescope’s imagery.
The research team explained that they employed Hubble’s Wide Field Camera 3 to obtain an accurate spectroscopical image of the distant galaxy. Spectroscopical instruments can split the light emitted by a space object into its basic colors.
Next, scientists took a look at the object’s “redshit” to estimate the distance. According to the team, the redder the wavelengths of a galaxy, the farther that galaxy is because as light travels to longer distances to reach our telescopes it gets stretched to those wavelengths on the spectrum.
Gabriel Brammer of the STScI, which also operates Hubble, noted that the galaxy was located exactly at the distance limit beyond which Hubble is out of range. The previous record holder was a galaxy with a redshift of 8.68 (GN-z11 has a redshift of 11.1).
Pieter van Dokkum, another Yale researcher involved in the finding, explained that Hubble shattered all previous distance records of much better ground-based telescopes. Van Dokkum expects the record to be broken once more but by the James Webb Space Telescope.
Astronomers also learned that the newly detected galaxy is 25 smaller than our galaxy, and it hosts just 1% of the Milky Way’s stellar mass. Nevertheless, GN-z11 is expanding fast, with a star creation rate 20 times greater than the Milky Way’s.
A paper on the recent discovery was published in the Astrophysical Journal.
Image Source: NASA.gov