Using the VLT, the team were also able to detect a weaker signal of hydrogen coming from the galaxy too. These two measurements allowed them to measure the distance of 13.28 billion light-years, which makes it the most distant galaxy with a precise distance measurement.
Note that these are not the first stars in the universe. In fact, in February this year we actually spotted the hydrogen signal from stars dating to just 180 million years after the Big Bang. However, it dramatically pushes back our understanding of the first galaxies.
The team think the galaxy is going through a high rate of star formation, producing about five stars every year compared to just one in the Milky Way. However, there’s something quite unusual about it, as they think the galaxy was brighter in the past; normally galaxies should get dimmer.
“From the star formation history we can see this object was brighter in the past,” Laporte said. “We know the first galaxies were merging, so there’s a possibility we could find more such bright objects in the past.”
And that’s quite important because it means future telescopes like the James Webb Space Telescope (JWST) could find more galaxies like this. If they were brighter in their youth, then at greater distances closer to the Big Bang they may be possible to spot.
Next up the team hope to work out if there’s a supermassive black hole at the center of this galaxy, like we see in more modern galaxies. For now, though, it’s giving us a fascinating insight into how our universe first started to take shape.
“With these new observations of MACS1149-JD1 we are getting closer to directly witnessing the birth of starlight!” Richard Ellis, also from UCL and a co-author on the paper, said in a statement. “Since we are all made of processed stellar material, this is really finding our own origins.”