According to a new study, spiral galaxies are going through a change, which was thought to be static billions of years ago.
Many unexpected changes were found in the shape of similar galaxies to our own. This was observed using the Keck telescopes in Hawaii and NASA's Hubble Space Telescope.
"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," Susan Kassin, a NASA astronomer and lead researcher of the study, said in a press release. "The trend we've observed instead shows the opposite, that galaxies were steadily changing over this time period."
It was learned that the disk-shaped galaxies like Milky Way and Andromeda Galaxy formed the present state nearly eight billion years ago, which is more than half the age of the universe. There were no changes expected until now the new study revealed much younger galaxies are forming towards a stable disk-shaped form.
"Previous studies removed galaxies that did not look like the well-ordered rotating disks now common in the universe today," co-auther Benjamin Weiner, an astronomer at the University of Arizona in Tucson, said in the report. "By neglecting them, these studies examined only those rare galaxies in the distant universe that are well behaved and concluded that galaxies didn't change."
The distant galaxies that are still creating stars seem to have more chaotic movements within. These galaxies' rotation is slower which is leading to more of internal movement and less fully disk-formed shape.
Scientists look forward to understand the changes in the universe by refining the computer simulations of galaxy evolution. The team has studied similarities with our Milky Way and chaotic blue galaxies. The way the changes are taking place in the blue galaxies it will form a more stable disk-shape like Milky Way.