Written by Francis Reddy
NASA’s Goddard Space Flight Center
Greenbelt, MD – A comprehensive study of hundreds of galaxies observed by the Keck telescopes in Hawaii and NASA’s Hubble Space Telescope has revealed an unexpected pattern of change that extends back 8 billion years, or more than half the age of the universe.
“Astronomers thought disk galaxies in the nearby universe had settled into their present form by about 8 billion years ago, with little additional development since,” said Susan Kassin, an astronomer at NASA’s Goddard Space Flight Center in Greenbelt, MD, and the study’s lead researcher. “The trend we’ve observed instead shows the opposite, that galaxies were steadily changing over this time period.”