The galaxy NGC 7172 is located approximately 110 million light-years from Earth in the constellation Piscis Austrinus. It was discovered on September 23, 1834 by the English astronomer John Herschel , son of the famous astronomer William Herschel. His son, among other things, popularized the use of the Julian date in astronomy and invented cyanotype.
Also known as ESO 466-38, IRAS 21591-3206, or LEDA 67874, this galaxy is 85,000 light-years in diameter and is now being viewed through the eyes of the NASA-ESA Hubble Space Telescope.
NGC 7172 is not an ordinary spiral galaxy, for when astronomers examined the galaxy across the electromagnetic spectrum they found that it is a Seyfert galaxy , a type of galaxy with an intensely luminous active galactic nucleus fueled by matter accumulating in a supermassive black hole.
“When we surveyed NGC 7172 across the electromagnetic spectrum, we quickly discovered that there was more to it than meets the eye,” the Hubble astronomers explain.
The dust lane winding its way through NGC 7172, seen from the side in this image , is obscuring the galaxy’s luminous heart , making NGC 7172 look like nothing more than a normal edge-on spiral galaxy.
The resulting image is the result of several observations by Hubble’s Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3) instruments in the infrared and optical parts of the spectrum and three filters to sample various wavelengths.
As a curiosity, given its visual magnitude of 13.61, NGC 7172 is visible with the help of a telescope that has an aperture of 350 mm or more.
Reference: NASA / ESA / Hubble / DJ Rosario / A. Barth / L. Shatz.
