The previously held belief had it that most disc galaxies formed more or less into their present shape eight billion years ago, a little more than half of the universe’s estimated age. New data reveals that while Andromeda and the Milky Way have largely settled into a condition where rotation and orderly movement dominates, more distant blue galaxies are more disorderly, still finding their orbital footing, so to speak.
Blue galaxies are identifiable by color and are known to be galaxies where stars are forming. The distant blue galaxies being studied in this project have been shown to be slowly developing into orderly, rotating galaxies like our own.
The study surveyed all galaxies with emission lines visible enough to reliably track interior motion. The results have contradicted a decades-old presumption that all galaxies must be ordered around rotation in order to hold together, but as we see, some galaxies are still coming into shape billions of years after first forming.
An in-depth paper on the findings was published on October 20th, and should provide some intensive reading material for professional and armchair astronomers alike.
Led by the Lick Observatory at the University of California Santa Cruz in collaboration with researchers at Berkeley, the University of Hawaii in Manoa, Johns Hopkins University in Baltimore, the University of Chicago and Pasadena’s California Institute of Technology, the DEEP2 survey has found a sharp decrease in the number of mergers between galaxies in the last eight billion years.
The data gathered from the survey should lead to more accurate and informed computer simulations of the forces at play in the forming of galaxies and the universe.
There is some fascinating video and photography related to the project available at NASA’s official website.
The Hubble telescope is the result of an international collaboration between NASA and the European Space Agency. The scope is being operated by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, while the Space Telescope Science Institute (STScI) in Baltimore processes the scope’s findings, while STScl themselves are operated by the Association of Universities for Research in Astronomy, Inc. located in Washington.
The 544 galaxies surveyed are located anywhere from two to eight billion light years away and range in size from 0.3 to 100 percent the mass of our own galaxy. Watching smaller galaxies develop has been tremendously informative in determining how our own works, and the data being mined by this project should have some tremendous applications to the rest of the astronomy field as well as astrophysics.
Historically, studies have overlooked disordered galaxies, focusing on the, in fact, quite rare ordered galaxies which are not at all the norm throughout the universe. This discovery has potentially put millions of galaxies back on the radar for future studies.