Photo from V. Tilvi, S.L. Finkelstein, C. Papovich, and the Hubble Heritage Team.
Last week, astronomers confirmed that they have spotted the farthest and oldest galaxy ever discovered.
We’re seeing the galaxy as it existed when our universe was a mere 700 million-years-old, which is about 5 percent of its current age — 13.8 billion years. This means that the light from the galaxy has been travelling towards Earth for almost as long as our universe has existed.
A quick lesson will help clear up why we’re seeing the galaxy as it existed so long ago: Light can only travel at so fast a speed through space — creatively titled, the speed of light. The speed of light is fast, clocking in at around 186,000 miles per second, but space is darn big and light takes a while to travel across it. The galaxy’s distance from us is measured in light-years, which is the distance light travels in a year. In short, the galaxy’s light has been travelling towards Earth for over 13 billion years, meaning it was just over 13 billion light-years away when it sent the light.
Another interesting fact: our universe is expanding. The universe was created during the Big Bang, when all matter shot out in every direction. This matter, which makes up our universe, has continued spreading out in every direction since. Sort of like a firework that started from nothing and never burned out or felt the effects of gravity. That being said, maybe not so much like a firework, but you get the picture.
Because of our expanding universe, astronomers predict that the newly discovered galaxy has been moving away from us and is now actually 30 billion light years away, but was around 13 billion light years away when it formed.
The galaxy, called z8_GND_5296, was seen using a combination of the Hubble Space Telescope and the Keck I telescope in Hawaii, which allowed astronomers to see even farther than they ever have before.
An interesting and unusual thing about this galaxy is that it was “giving birth to” new stars at 150 times the rate of the Milky Way. Think octo-mom. Think octo-galaxy. This galaxy beat the distance record set by another galaxy last year, which was located in the same part of the sky and also produced stars at a rapid rate.
“It could be that we found two weirdoes, but now we’ve found two weirdoes in the same Hubble image in this tiny little region of the sky,” said lead astronomer of the discovery Steven Finkelstein in an interview with Space.com. “More than likely, they’re not weirdoes. I think what it’s telling us is that in the distant universe you can actually make a decent number of these galaxies.”
Just like many space discoveries, this galaxy stands as a puzzle piece for finding out more about our universe. This discovery gave us a glimpse of what a galaxy looked like shortly after the Big Bang and will help astronomers figure out more about the early universe. From here scientists can continue to unlock the mysteries of the universe and our own Milky Way and while they’re at it, maybe work on the mystery of what exactly is in the vegan chicken at the diner.
