The NASA/ESA Hubble Space Telescope has taken a picture of the galaxy NGC 7640.
This Hubble image shows the barred spiral galaxy NGC 7640, which lies in the constellation Andromeda, about 38.8 million light-years away. Image credit: NASA / ESA / Hubble.
Discovered on October 17, 1786 by the English astronomer William Herschel, NGC 7640 is an 11th magnitude barred spiral galaxy.
Also known as LEDA 71220, UGC 12554 and IRAS 23197+4034, this galaxy is located in the constellation Andromeda, 38.8 million light-years from Earth.
Galaxies of this type are recognizable by their spiral arms, which fan out not from a circular core, but from an elongated bar cutting through the galaxy’s center.
NGC 7640 might not look much like a spiral in this Hubble image, but this is due to the orientation of the galaxy with respect to the space telescope.
There is evidence that this galaxy has experienced some kind of interaction in its past.
Galaxies contain vast amounts of mass, and therefore affect one another via gravity. Sometimes these interactions can be mild, and sometimes hugely dramatic, with two or more colliding and merging into a new, bigger galaxy.
Understanding the history of a galaxy, and what interactions it has experienced, helps astronomers to improve their understanding of how galaxies — and the stars within them — form.
The color image was made from separate exposures taken in the visible and near-infrared regions of the spectrum with Hubble’s Advanced Camera for Surveys (ACS).
It is based on data obtained through two filters: a broad V-band (F606W) filter and a near-infrared (F814W) filter.
The color results from assigning different hues to each monochromatic image associated with an individual filter.
