NASA’s imperious Hubble Telescope has just destroyed the cosmic distance record, successfully measuring the farthest-away galaxy ever seen in the universe.
When Hubble looks at galaxies, stars and exoplanets around our universe it does so through a relative form of time travel. The further it looks away from us, for example, the further it peers into our universe’s past.
So, by measuring GN-z11, a “surprisingly bright” infant galaxy at the edge of the universe, the latest team of international researchers to use the telescope has leapt farther back than ever.
The world is gone backwards
‘We’ve taken a major step back in time,’ is usually a negative term when you hear an official say it, conjuring up grisly scenes of societal issues we thought were long gone.
However, this time, for once, it’s a glowing positive.
“We’ve taken a major step back in time, beyond what we’d ever expected to be able to do with Hubble,” explained principal investigator Pascal Oesch of Yale University. “We see GN-z11 at a time when the universe was only 3pc of its current age.”
To put a number on that, the team think that GN-z11’s mapping shows it at just 400m years after the Big Bang.
Hubble and Spitzer reign supreme
It wasn’t all Hubble, though, with the Spitzer Space Telescope providing some colour imaging to help astronomers measure the distance of GN-z11.
The combination of Hubble’s and Spitzer’s imaging reveals that GN-z11 is 25 times smaller than the Milky Way and has just 1pc of our galaxy’s mass in stars.
However, the ‘newborn’ galaxy is growing fast, forming stars at a rate about 20 times greater than our galaxy does today.
This makes for an extremely remote galaxy bright enough for astronomers to find and perform detailed observations with both Hubble and Spitzer.
Hubble, still got it
There’s a significant amount of surprise surrounding this finding, with many astronomers not expecting to see such distant galaxies so clearly until a new telescope, NASA’s upcoming James Webb Space Telescope, is deployed.
But there’s still life in the old Hubble yet, as it nears its 26th birthday in space.
“It’s amazing that a galaxy so massive existed only 200 million to 300 million years after the very first stars started to form. It takes really fast growth, producing stars at a huge rate, to have formed a galaxy that is a billion solar masses so soon,” explained investigator Garth Illingworth of the University of California, Santa Cruz.
“This new discovery shows that the Webb telescope will surely find many such young galaxies reaching back to when the first galaxies were forming.”