| Story Views | |
| Now: | |
| Last Hour: | |
| Last 24 Hours: | |
| Total: | |
Anne’s Image of the Day: Spiral Galaxy NGC 1055
read more at Anne’s Astronomy News http://annesastronomynews.com/
August 25, 2013
NGC 1055, an edge-on spiral galaxy in Cetus
Image Credit & Copyright: Ken Crawford, Rancho Del Sol Observatory. (In collaboration with the Dr. David Martinez-Delgado Star Stream Survey)
NGC 1055 is a barred spiral galaxy of some 115,800 light-years across, located about 52 million light-years away from Earth in the constellation of Cetus (the Whale), while it is receding from us at approximately 994 kilometers per second.
This big edge-on spiral is interacting with the bright barred spiral galaxy Messier 77 of some 170,000 light-years across. These two are the largest galaxies of the M77 Group, a small galaxy group that also includes spiral galaxy NGC 1073, and five other small irregular galaxies. The separation between NGC 1055 and Messier 77 is about 442,000 light-years.
NGC 1055 has a prominent nuclear bulge crossed by a wide, knotty, dark lane of dust and gas. Many bright blue star clusters stand out against its dark dust lanes. The spiral arm structure appears to be elevated above the galaxy’s plane and obscures the upper half of the bulge.
The galaxy is a bright infrared and radio source. Astronomers believe that this results from unusually active star formation hidden behind a thick curtain of dust, what is an indications of a recent encounter that has stirred up star formation and is providing food for its core’s black hole. The star clusters contain a great number of very short lived super massive stars. Yet another indication of something is triggering unusually strong star formation in NGC 1055.
This image also shows a curious box-shaped inner halo extending far above and below the galaxy’s dusty plane. The halo itself is laced with faint, narrow structures, and could represent the mixed and spread out debris from a satellite galaxy disrupted by the larger spiral some 10 billion years ago.
n/a
Source: http://annesastronomynews.com/annes-image-of-the-day-spiral-galaxy-ngc-1055/
