Have you ever looked up at the night sky and wondered what else is up there? Astronomers feel the same way and many of them study space in search of distant galaxies that they can compare to our own. The more astronomers learn about other planets and galaxies, the better they can understand our own.
Astronomers recently discovered the oldest and furthest galaxy yet. Galaxy z8_GND_5296 is the name of the newly found galaxy and scientists believe that it formed formed 700 million years after the Big Bang. The universe is 13.8 billion years old.
They also discovered that this galaxy, like many other older ones that have been discovered, can product stars much faster than our own. In fact, that’s how astronomers were able to find the galaxy.
Scientists use a technique called spectroscopy, to look for the chemical signatures of elements.The spectroscopy was able to recognize hydrogen, which is the main fuel of stars. Spectroscopy measures the change in the wavelengths of a galaxy’s light as it travels towards Earth, specifically how much it shifts towards the red end of the spectrum.
University of California at Riverside, University of Texas at Austin, Texas A&M University and the National Optical Astronomy Observatories all had a hand in helping locate the galaxy. They sorted through Hubble Space Telescope images of more than 100,000 galaxies. Based on color, they selected 43 candidates to study further.
“The most reliable way to select galaxies is to use the color because the further out you go in the universe, galaxies get redder and redder,” UC Riverside’s Bahram Mobasher explained. “So, that is an indication of the distance.” The color shifts as a galaxy expands over time.
Astronomers are hoping to study the galaxy to determine how older galaxies were formed and how they differ from newer galaxies. They are confident they will continue to find older and more distant galaxies in the near future.
Image from Wikimedia Commons.