Hubble Space Telescope has discovered the most distant galaxy that acts as a cosmic magnifying glass.
According to the scientists, the "lensing" galaxies are so massive that their gravity bends, magnifies, and distorts light from objects behind it, a phenomenon called gravitational lensing.
Scientists revealed that the object behind the cosmic lens is a tiny spiral galaxy undergoing a rapid burst of star formation and its light has taken 10.7 billion years to arrive here and seeing this chance alignment at such a great distance from Earth is a rare find.
Lead researcher Kim-Vy Tran of Texas A and M University in College Station said that when you look more than 9 billion years ago in the early universe, you don't expect to find this type of galaxy lensing at all and it's very difficult to see an alignment between two galaxies in the early universe.
Team members Kenneth Wong and Sherry Suyu of Academia Sinica Institute of Astronomy and Astrophysics (ASIAA) in Taipei, Taiwan, used the gravitational lensing from the chance alignment to measure the giant galaxy's total mass, including the amount of dark matter, by gauging the intensity of its lensing effects on the background galaxy's light. The giant foreground galaxy weighs 180 billion times more than our sun and is a massive galaxy for its time. It is also one of the brightest members of a distant cluster of galaxies, called IRC 0218.
The team suspects the lensing galaxy continued to grow over the past 9 billion years, gaining stars and dark matter by cannibalizing neighboring galaxies. Tran explained that recent studies suggest these massive galaxies gain more dark matter than stars as they continue to grow.
The distant galaxy is too small and far away for Hubble to determine its structure. So, team members analyzed the distribution of light in the object to infer its spiral shape. In addition, spiral galaxies are more plentiful during those early times. The Hubble images also revealed at least one bright compact region near the center.
The study was published in The Astrophysical Journal Letters.