Thirty-six light years across and still growing, it was born in fire and wind about 20,000 light years from earth when a star exploded and sent dust and gas flying through the galaxy at tremendous speed. Some 1,500 or 2,000 years later, the Chandra X-ray Observatory captured this beautifully detailed image and released it to the public on October 23, 2007. This is the Chandra G292.0+1.8 supernova remnant, located in our galaxy, in the constellation Centaurus.
Constellations like Centaurus aren’t real clusters of stars. They are really unrelated stars at different distances from earth that just happen to look close together. This group of unrelated stars looked to some of our ancestors as if they outlined a centaur, a legendary creature said to be half human and half horse, so they called the constellation Centaurus. Apparently, they had great imaginations!
But galaxies are real clumps of stars. Huge swirling clumps of different shapes containing billions of stars each. The Milky Way is a pinwheel-shaped galaxy 100,000 light years across, known as a spiral galaxy. We can’t take a picture of the whole Milky Way, because we live inside it; but it would look very much like the NGC 6744 galaxy shown here. Spectacular!
There isn’t enough time in an astronomer’s life to count that many stars. Besides that, many stars are hidden behind clouds of gas and dust. But various estimates are that our galaxy, the Milky Way, contains between 100 billion and a trillion stars. (The most common estimate seems to be about 200 billion, or 200,000,000,000 stars.)
You couldn’t count that many stars if you lived 1,000 years! Even if you COULD see them all from earth.
Anway, Chandra G292.0+1.8 is physically located in our Milky Way galaxy, in the direction of Centaurus. This beautifully detailed Chandra composite shows the rapidly expanding shell of gas formed by the explosion.
A pulsar located slightly below and to the left of the center is believed to be the star that exploded to form the nebula. While it would normally have been at the center of the remnant, recoil from the lopsided explosion may have kicked the pulsar in this direction.
The long white line running from left to right across the center is called the equatorial belt, and was probably formed when the star expelled material from around its equator shortly before it died.
Our universe is filled with incredible violence and chaos, but it produces some of the most beautiful and fascinating structures we can imagine.