Features

Galaxies Colliding in the Night

Welcome to the real universe, where giant galaxies devour their neighbors and collisions may give birth to black holes.

Galileo’s Dazzling Flyby

The intrepid spacecraft’s first orbit of Jupiter found it imaging cracked, icy Europa, volcano-ravaged Io, and the Great Red Spot.

Sky Almanac

The Moon’s monthly trek across the sky brings it close to four bright planets and two fine star clusters.

A Deep-Sky Romp Through Fall Skies

Hop your way among the stars to the best clusters, nebulae, and galaxies the autumn sky has to offer.

It’s Hip to Be Square

The Great Square of Pegasus, the body of a celestial horse and autumn’s most prominent asterism, harbors a wealth of intriguing objects for the naked eye, binoculars, and telescope.

Exploring Cassiopeia’s Bright Clusters

Nearly overhead on November evenings, this stunning constellation holds dozens of the Milky Way’s finest star clusters.

A Winter Rich in Meteors

The next three months offer three meteor showers worth your attention: the possibly stormy Leonids, the always reliable Geminids, and the frigid-weather Quadrantids.

Departments

Behind the Scenes
Letters
AstroForum
AstroNews
Amateur News
Astronomy Books
AstroBytes
Meetings and Events
Resources & Photofacts
New Products
Advertiser Index
Reader Reports
Ultimate Exposure