This Hubble image shows the spiral galaxy UGC 11397.
ESA/Hubble & NASA, M. J.
Koss, A. J. Barth
The light that the NASA/ESA Hubble
Space Telescope collected to create this image reached the telescope after a
journey of 250 million years. Its source was the spiral galaxy UGC 11397, which
resides in the constellation Lyra (The Lyre). At first glance, UGC 11397
appears to be an average spiral galaxy: it sports two graceful spiral arms that
are illuminated by stars and defined by dark, clumpy clouds of dust.
What sets UGC 11397 apart from a
typical spiral lies at its center, where a supermassive black
hole containing 174 million times the mass of our Sun grows. As a black
hole ensnares gas, dust, and even entire stars from its vicinity, this doomed
matter heats up and puts on a fantastic cosmic light show.
Material trapped by the black hole
emits light from gamma rays to radio waves, and can brighten and fade
without warning. But in some galaxies, including UGC 11397, thick clouds of
dust hide much of this energetic activity from view in optical light. Despite
this, UGC 11397's actively growing black hole was revealed through its bright
X-ray emission — high-energy light that can pierce the surrounding dust. This
led astronomers to classify it as a Type 2 Seyfert galaxy, a category used for
active galaxies whose central regions are hidden from view in visible
light by a donut-shaped cloud of dust and gas.
Using Hubble, researchers will study hundreds of galaxies that, like UGC 11397, harbor a supermassive black hole that is gaining mass. The Hubble observations will help researchers weigh nearby supermassive black holes, understand how black holes grew early in the universe’s history, and even study how stars form in the extreme environment found at the very center of a galaxy.
Source: Hubble Captures an Active Galactic Center - NASA Science
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