As the world gets ready to witness the amazing performance of the James Webb Telescope, set to launch in 2018, NASA scientists wanted to test one more time the limits of the already-acclaimed Hubble Space Telescope and attempt to measure the distance to the farthest galaxy known so far.
Researchers have just published a study in the Astrophysical Journal, detailing their use of Hubble’s Wide Field Camera 3 in a successful attempt to measure the distance to GN-z11.
This high-redshift galaxy is located at the constellation Ursa Major and it is the most distant and oldest known galaxy in the Universe. It is located around 32 billion light-years away from our planet and researchers were able to observe it as it existed some 13.4 billion years ago, only 400 million years from the Big Bang.
In their study, the astronomers explain that they were able to measure its distance to Earth spectroscopically, by dividing the light into its component colors, a technique which they say has a high degree of accuracy.
Previously, scientists had measured the distance to GN-z11 through a different method, by analyzing the colors depicted in images taken by the Spitzer Space Telescope and the Hubble Space Telescope.
Those studies concluded that the galaxy was nearer to Earth, however these spectroscopic observations show that it’s actually farther away, which proves Hubble’s observation capacity is actually greater than initially believed.
The researchers note that even though GN-z11 galaxy appears faint, it is actually unexpectedly bright for such a long distance.
In order to determine cosmic distances, scientists need to measure the object’s redshift based on the Doppler effect technique. Since all distant objects from the Universe seem to draw back from us, their light is actually extended to longer, redder wavelengths.
It wasn’t so long ago that scientists believed EGSY8p7 to be the farthest galaxy from Earth, with a redshift of 8.68. Now, however, they have discovered that Gn-z11’s redshift is at 11.1, which means it’s the new title holder for the most distant cosmic system in the Universe.
The data collected by scientists reveals the fact that this infant galaxy is actually 25 times smaller than the Milky Way and even though it encompasses just 1% of our galaxy’s mass in stars, their numbers are growing fast.
Apparently, this distant galaxy is creating stars 20% faster than the Milky Way, which makes it bright enough for NASA’s space telescope to observe it in detail.
Image Source: SpaceTelescope