NASA’s James Webb Telescope has discovered the oldest galaxy in the universe that existed 13.5 billion years ago.

The collection of stars – called GLASS-z13 – dates to just 300 million years after the big bang. This bests the previous oldest galaxy, known as GN-Z11, spotted by the Hubble Space Telescope by 100 million years.

The researchers, from the Harvard and Smithsonian Centre of Astrophysics in Massachusetts, also discovered a second called GLASS-z11.

Both of the galaxies have a mass equivalent to one billion suns, which the team suggests is what they would expect from 500 million-year-old – which could indicate that the stars formed even earlier than scientists think.

They are also relatively small compared to our own Milky Way, which is 100,000 light-years in diameter; GLASS-z13 is approximately 1600 light years across while GLASS-z11 is 2300 light years wide.

GN-Z11

Red spot with white heart

The galaxy GN-Z13, which looks like a red spot with a white heart, was found using the NIRCam Infrared Camera, on board the James Webb Space Telescope, which is capable of detecting light from the oldest stars and galaxies.

The James Webb telescope uses a wide range of infrared light to see the “past time”, and this is done by analyzing the time it takes for the light to travel through space.

When the data is translated from infrared radiation into the visible spectrum, it appears as a red patch with white in its center, as part of a larger picture of the distant universe called the “deep field”.

GN-Z13

“We found two very compelling candidates for extremely distant galaxies,” says Rohan Naidu, a graduate student in the university’s astronomy department, told New Scientist.

“If these galaxies are at the distance we think they are, the universe is only a few hundred million years old at that point.”