Sagittarius has a bit of an identity crisis. It’s easy to see – just not as what it’s supposed to be. In mythology, Sagittarius was known as the archer. But that title doesn’t tell the whole story. He was actually a centaur – a creature with the head and torso of a man, but the body and legs of a horse. He was holding a bow, however – aimed at the nearby scorpion.
To modern eyes, though, the constellation looks like something a little less fearsome: a teapot. It’s low in the south-southeast at nightfall, with the handle to the left and the spout to the right. If you have even moderately dark skies, it’s not hard to find.
Sagittarius lies along the glowing band of the Milky Way – millions of stars that outline the disk of the Milky Way Galaxy. And the constellation contains the brightest part of the Milky Way – the Large Sagittarius Star Cloud. It appears to rise from the spout of the teapot like a cloud of steam. It’s so bright because it’s toward the center of the galaxy, so we’re looking through a thick layer of stars.
The center itself is concealed behind clouds of light-absorbing dust. So we don’t see the full glory of the Milky Way’s core. Astronomers use instruments that are sensitive to infrared and other wavelengths to see through the dust.
The core also contains a supermassive black hole – a monster that’s more than four million times the mass of the Sun. We’ll have more about that tomorrow.
Script by Damond Benningfield