Top 10 exoplanets

Astronomers have discovered nearly 1,000 planets orbiting other stars. Here we highlight 10 of them.

Web Extra: Exoplanets on the edge

Many of the planetary systems orbiting other stars rank among the strangest objects humans have ever laid eyes on. Here are five more that stick out from this already eccentric crowd.

How Planck has redefined the universe

This new spacecraft has mapped the universe’s matter, refined its composition and age, and revealed thousands of radio sources.

Web Extra: How Planck maps the sky

This spacecraft has been observing the microwave sky since August 2009.

What makes a Great Comet?

Slight tweaks in the celestial recipe make a good comet great.

Web Extra: Score your favorite comets

Using Joseph Marcus’ comet scorecard, find out if your favorite comets are Great or just good.

Comet ISON brightens before dawn

This celestial visitor approaches naked-eye visibility.

Order from chaos — Genesis samples the solar wind

This NASA spacecraft captured and returned atoms from the Sun to Earth. What happened next took “recovery” to a whole new level.

10 great autumn binocular sights

Head outside to explore a nearby galaxy, a stellar waterfall, and more.

Web Extra: 10 top autumn binocular treats

All you need to enjoy these seasonal targets is a dark sky and good binoculars.

Spice up your images with Hydrogen-alpha data

Make your images shine by adding light through this narrow-band filter.

“Astronomy” tests Denkmeier’s Binotron-27

High-quality optics and superb mechanics make this accessory a winner.

In Every Issue

Astro News
Web Talk
Reader Gallery
New Products
Final Frontier