Scientists monitoring the Gaia observatory satellite found a “ghost” galaxy orbiting the far side of the Milky Way, according to data published by the European Space Agency (ESA).
Antlia 2 is the “most diffuse and lowest surface brightness galaxy ever detected,” and it was made even more difficult to find due to its position on the far side of the Milky Way, obscuring it from earthly view, reported Forbes. At 130,000 light years from the Milky Way, Antlia 2 joins other star clusters on the list of the Milky Way’s satellite galaxies.
Antlia 2, however, is notably dim, according to Gabriel Torrealba, team leader of Taiwan’s premier astrology and astrophysics lab. The newly discovered galaxy is about one-third the size of the Milky Way and is about 10,000 times dimmer than the similarly sized Large Magellanic Cloud satellite galaxy. (RELATED: OPINION: Is Space Exploration Motivated By Nationalism?)
“It’s not completely clear how this galaxy came to be so ghostly,” Torrealba told Forbes.
Story @sciencemagazine about a newfound, weirdly dim galaxy called Antlia 2: https://t.co/aTG50O423E Quote from Andrey Kravtsov of the #Kavli Institute @UChicago: “It’s a very odd object and kind of exciting because we don’t know yet how to interpret all of its properties.” pic.twitter.com/7MCVm0DEz4
— The Kavli Foundation (@KavliFoundation) November 15, 2018
The galaxy is held together loosely and is stretched by the gravity of the Milky Way. Its lack of coalescence adds to its wispy appearance and is why ESA scientists described it as diffuse.
“The simplest explanation of why Antila 2 appears to have so little mass today is that it is being taken apart by the Galactic tides of the Milky Way,” Sergey Koposov of Carnegie Mellon University said, according to Metro.
Antlia 2 managed to hide from astronomers until now by sitting directly on the other side of the Milky Way. To view Antlia 2, scientists have to peer through light years of dust and stars, past the bright center of our galaxy, to see it. The area obscured by the Milky Way’s center that Antlia 2 is in is called “the zone of avoidance.”
“The zone of avoidance is basically the part of the sky obscured by the Milky Way’s disk as seen from the Earth. The disk of the Milky Way has a lot of gas and stars, making it extremely crowded and complex,” Torrealba said.
The dim and diffuse galaxy is also estimated by Torrealba to be one of the oldest dwarf galaxies in the universe.
Content created by The Daily Caller News Foundation is available without charge to any eligible news publisher that can provide a large audience. For licensing opportunities of our original content, please contact firstname.lastname@example.org.