Features

Speaking the language of the cosmos

Let’s take the scare factor out of equations and ask scientists a fundamental question: How much of astronomy is math?

Web Extra: 10 top equations in astronomy

Astronomers use math every day, and these 10 equations are some of their favorite tools.

Torrid Mercury’s icy poles

The MESSENGER spacecraft reveals water ice lurking in deeply shadowed craters.

Web Extra: Mercury in the spotlight

Planetary scientists have discovered water ice at Mercury’s poles that may have survived for billions of years, but other parts of this world seem surprisingly young.

Spacecraft: Where are they now?

What happens after planetary missions end?

Behind the scenes at Celestron

For more than 50 years, this innovative company has helped amateur astronomers observe the sky.

Comet ISON’s dazzling all-night show

This cosmic interloper should remain a grand sight throughout these long December nights.

Web Extra: Everything you need to know about Comet ISON

Check out Astronomy.com’s complete coverage of this visitor from the outer solar system.

11 top winter binocular gems

One supernova remnant, two double stars, and eight clusters beckon cold-weather skygazers.

Web Extra: 10 great winter binocular sights

All you need besides a clear, dark sky to see some fantastic seasonal sky treats are your binoculars.

Grab a Cometron scope to view Comet ISON

Celestron has made a pair of low-cost telescopes for beginners watching the great sky show.

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