Black Holes
If the Sun were compressed to a diameter of just four miles (6 km), its escape velocity would equal the […]
Exploding Stars
When a star like the Sun dies, it casts its outer layers into space, leaving its hot, dense core to
Colorful Dwarfs
The words astronomers use to describe stars evoke the fairy tales of childhood: white dwarfs, red giants, red dwarfs, and
Star Color and Energy
A star’s color provides a direct measurement of its surface temperature; the hottest stars shine blue-white, while the coolest are
Cosmic Beacons
One of the great mysteries of the ancient world was the nature of the stars. As people watched these twinkling
Our Star, the Sun
The Sun was born about 4.6 billion years ago from the gravitational collapse of a vast cloud of gas and