The winter sky features two bright, beautiful constellations that are often seen as rivals: Orion, the hunter, and Taurus, the bull. Star maps sometimes show Orion holding a shield to defend himself against Taurus.
Orion and Taurus are rivals in another sense, too: each illustrates a different way in which stars are born.
All stars are born from vast clouds of gas and dust. But not all of these clouds give birth to all types of stars.
The clouds of Orion are creating all kinds of stars -- massive ones that'll explode as supernovae, and lesser ones that'll live long, quiet lives. The perfect example is the Orion Nebula, which is about 1300 light-years away. It's given birth to thousands of stars -- and it's so bright that it's visible to the unaided eye.
Taurus is also giving birth to new stars, but none of them is massive enough to explode. The most massive newborn stars in Taurus are only about as heavy as the Sun. An example is a star known as T Tauri. It's 480 light-years away, and it's the prototype of young Sun-like stars.
Orion and Taurus are in great view right now. They're in the southeast at nightfall. Look for Orion's Belt -- a short line of three bright stars. Taurus is above Orion, marked by its V-shaped face and its orange eye, the star Aldebaran.
And when you gaze at these mythological rivals, you'll know that Orion and Taurus are also astronomical rivals, showing us different ways to make stars.
Script by Ken Croswell, Copyright 2008
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