James Webb discovers oldest galaxy in the universe

The James Webb Space Telescope has captured a new image that shows the oldest galaxy ever observed.

Using its incredibly sensitive NIRCam instrument, the infrared space observatory found a 13.5 billion-year-old galaxy only days after its science operations began.

The galaxy, called GLASS-z13 (GN-z13), formed just 300 million years after the Big Bang that occurred 13.8 billion years ago.

The previous record holder, discovered by the Hubble Telescope in 2015, was GN-z11 that dates back 400 million years after the universe birthed.

NASA revealed the first stunning James Webb images last week. Since that time, the James Webb team has also revealed images of Jupiter and of the spiral galaxy Messier 74 (M74). 

Scientists from the Harvard and Smithsonian Center of Astrophysics released two preprint articles about the new discovery on Wednesday, July 20. In their papers, they explained that they also detected another galaxy of a similar age, called GLASS-z11.

The researchers said that both newly-detected galaxies are small compared to the Milky Way. GLASS-z13 is roughly 1,600 light-years wide, GLASS z-11 is approximately 2,300 light-years, and the Milky Way is 100,000 lightyears in diameter. This is to be expected, as the Milky Way, which is more than 13 billion years old itself, has had much more time to accumulate mass by cannibalizing smaller galaxies.