. | . |
MPIA: Fast-Growing Galaxies Could Solve Cosmic Riddle by Staff Writers Heidelberg, Germany (SPX) May 26, 2017
Astronomers have discovered a new kind of galaxy in the early universe, less than a billion years after the Big Bang. These galaxies are forming stars more than a hundred times faster than our own Milky Way. The discovery could explain an earlier finding: a population of surprisingly massive galaxies at a time 1.5 billion years after the Big Bang, which would require such hyper-productive precursors to grow their hundreds of billions of stars. The observations also show what appears to be the earliest image of galaxies merging. The results, by a group of astronomers led by Roberto Decarli of the Max Planck Institute for Astronomy, have been published in the 25 May issue of the journal Nature. When a group of astronomers discovered unusually massive galaxies in the early universe a few years ago, the sheer size of these galaxies, with hundreds of billions of stars, posed a puzzle. The galaxies are so distant, we see them as they were a mere 1.5 billion years after the Big Bang, when the universe was about 10% its present age. How were they able to form so many stars, in such a comparatively short time? Now, a serendipitous discovery by a group of astronomers led by Roberto Decarli from the Max Planck Institute for Astronomy is pointing to a possible solution to the mystery: a population of hyper-productive galaxies in the very early universe, at a time less than a billion years after the Big Bang. Roberto Decarli says: "We were looking for something different: for star formation activity in the host galaxies of quasars. But what we found, in four separate cases, were neighboring galaxies that were forming stars at a furious pace, producing a hundred solar masses' worth of new stars per year." Quasars constitute a brief phase of galaxy evolution, powered by the infall of matter onto a supermassive black hole at the center of a galaxy. Fabian Walter, leader of the observation program using the ALMA observatory in Chile that led to the discovery, says: "Very likely it is not a coincidence to find these productive galaxies close to bright quasars. "Quasars are thought to form in regions of the universe where the large-scale density of matter is much higher than average. Those same conditions should also be conducive to galaxies forming new stars at a greatly increased rate." Whether or not these newly discovered galaxies can indeed be the precursors of their more massive, later kin, and thus solve the cosmic puzzle, will depend on how common they are in the universe. That is a question for follow-up observations planned by Decarli and his colleagues. The ALMA observations also showed what appears to be the earliest known example of two galaxies undergoing a merger. In addition to forming new stars, mergers are another major mechanism of galaxy growth - and the new observations provide the first direct evidence that such mergers have been taking place even at the earliest stages of galaxy evolution, less than a billion years after the Big Bang.
Baltimore, MD (SPX) May 22, 2017 Astronomers with the Sloan Digital Sky Survey (SDSS) have created the first map of the large-scale structure of the universe based entirely on the positions of quasars. Quasars are the incredibly bright and distant points of light powered by supermassive black holes. "Because quasars are so bright, we can see them all the way across the universe," said Ashley Ross of the Ohio State Univers ... read more Related Links Max Planck Institute For Astronomy Understanding Time and Space
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |