Quasar Host Galaxies
Click on image for full size
Hubble Space Telescope image courtesy of STScI
Quasi Stellar Objects: Quasars and Active Galaxies
Quasars, or quasi stellar objects, are named that way because they are point-like objects just like stars. However, they are nothing like stars. From analysis they are determined to be very distant, some are the most distant objects that we can see. But they are also very bright. Such intensity seen by Earth at such great distances indicates that they are very energetic. What could they be? For many years Astronomers were baffled.
It has now been determined that Quasars are most likely the centers of Active Galaxies. In the center of many galaxies there may rest supermassive Black Holes. Around these Black Holes gigantic discs of matter falling onto them form. This matter is heated to unimaginably high temperatures and hence shines so bright that some Active Galactic Nuclei outshine their host galaxies.
Black Holes also form jets of matter that shoot out from the center of the galaxy. These jets can shoot out for Millions of Light-Years. Quasars are special Active Galactic Nuclei that have their jets lined up with our line of sight. So we are looking straight down the jet and it seems extraordinarily bright.
You might also be interested in:
In the 1960's, the United States launched some satellites to look for very high energy light, called Gamma Rays. Gamma Rays are produced whenever a nuclear bomb explodes. The satellites found many bursts...more
During the early 1900's, which is not very long ago, astronomers were unaware that there were other galaxies outside our own Milky Way Galaxy. When they saw a small fuzzy patch in the sky through their...more
Neutron Stars are the end point of a massive star's life. When a really massive star runs out of nuclear fuel in its core the core begins to collapse under gravity. When the core collapses the entire star...more
Spiral galaxies may remind you of a pinwheel. They are rotating disks of mostly hydrogen gas, dust and stars. Through a telescope or binoculars, the bright nucleus of the galaxy may be visible but the...more
When stars like our own sun die they will become white dwarfs. As a star like our sun is running out of fuel in its core it begins to bloat into a red giant. This will happen to our sun in 5 Billion years....more
What's in a Name: Arabic for "head of the demon" Claim to Fame: Represents Medusa's eye in Perseus. A special variable star that "winks" every 3 days. Type of Star: Blue-white Main Sequence Star, and...more
What's in a Name: Nicknamed the "Pup" because it is the companion to Sirius, "the Dog Star" Claim to Fame: Highly compressed white dwarf remnant. Density about 50,000 times that of water. It has approximately...more