It is the big one that didn’t get away.
This image of UGC 2885 – a majestic spiral galaxy 2.5 times wider than our Milky Way with 10 times as many stars – sparked widespread interest last week when released at the American Astronomical Society meeting in Honolulu, Hawaii.
Nicknamed ‘Rubin’s Galaxy,’ after astronomer Vera Rubin (1928-2016), the galaxy is located 232 million light-years away in the northern constellation Perseus.
But how did this one get so big? That is the question astronomers across North America, including Physics and Astronomy professor Pauline Barmby, are exploring currently.
Photographed by the Hubble Space Telescope, UGC 2885 is a “gentle giant,” according to researchers, who say it looks like it has been sitting quietly for billions of years, possibly sipping hydrogen from the filamentary structure of intergalactic space. This fuels modest ongoing star birth at half the rate of our Milky Way.
In fact, its supermassive central black hole is a sleeping giant, too. Because the galaxy does not appear to be feeding on much smaller satellite galaxies, it is starved of infalling gas.
“It is a beautiful galaxy, in my biased opinion,” Barmby explained. “Hubble has revolutionized the study of how stars form, grow and die in galaxies outside our own. It is remarkable we can create such a detailed image of a galaxy so far away – a lot of that detail is because this galaxy is so big.”
Normally, giant galaxies exist in forms outside a spiral. That is what makes UGC 2885 so unique – size and shape.
Barmby, a member of Western Space, uses star clusters to understand the age of galaxies. Her expertise will provide valuable insights into the age of UGC 2885. “It is a way of tracing the history of the galaxy which, we hope, will give us some idea of how you could make such a big galaxy.”
This image release was done in collaboration with researchers across North America, including Barmby, Rupali Chandar of the University Toledo, S. Ford of the American Museum of Natural History, Jeremy Bailin of the University of Alabama and M. Peeples of the Space Telescope Science Institute.