Hot, dust-obscured galaxies on:
[Wikipedia]
[Google]
[Amazon]
A hot, dust-obscured galaxy, or hot DOG, is a rare type of quasar. The central black hole of such a galaxy emits vast amounts of radiation which heats the infalling dust and gas, releasing
A hot, dust-obscured galaxy, or hot DOG, is a rare type of quasar. The central black hole of such a galaxy emits vast amounts of radiation which heats the infalling dust and gas, releasing infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
light at a rate about 1,000 times as much as the Milky Way
The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. ...
, making these some of the most luminous galaxies in the universe. However, the density of the surrounding dust is so great that most of that light is obscured. Their average temperatures range from , significantly higher than an average galaxy's temperature of . They also appear to concentrate a much higher proportion of their galactic mass in the central black hole than is observed in normal galaxies.
Researchers believe that hot DOGs may represent a phase of galactic evolution where the central black hole is capturing material at a rate faster than new stars are forming, yet the radiation pressure from that rapid absorption is pushing away much of that surrounding material. The black hole will eventually clear its area of influence of the excessive dust and gas, rendering it a regular, visible galaxy.
These objects were first detected by the Wide-field Infrared Survey Explorer
Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and SMEX-6) is a NASA infrared astronomy space telescope in the Explorers Program. It was launched in December 2009, and placed in hibernation mode in February 201 ...
(WISE) in 2010, and only one out of every 3,000 quasars observed by ''WISE'' are of this type. Wu ''et al'' (2012) refer to these galaxies as "W1W2-dropouts" because they are faint or invisible in ''WISE'' W1 (3.4 μm) and W2 (4.6 μm) detection bands.
See also
*Luminous infrared galaxy
Luminous infrared galaxies or LIRGs are galaxies with luminosities, the measurement of brightness, above . They are also referred to as submillimeter galaxies (SMGs) through their normal method of detection. LIRGs are more abundant than starburst ...
References
External links
* {{Galaxy * 2012 in science