Features

What happens when galaxies collide?

Bursts of star formation and tails of debris litter the cosmos whenever galaxies meet.

How the universe has surprised us

Unexpected phenomena have steered astronomy in new directions.

Ready, set, boom!

An expanding bubble enriches the galaxy and may help life begin.

Evolution at the edge

Astronomers find that comets are not the pristine relics we thought they were.

Discover fall’s splendid sky sights

Colorful doubles and stellar death shrouds are among tonight’s deep-sky wonders.

The day the Sun disappeared

Astronomy editors went to two exotic locales to bask in the Moon’s shadow.

Stalking star clouds

A small telescope and bright sky don’t stop this imager’s hunt for the big and beautiful.

Explore the sky with classic glass

Telescopes from the golden age of observing provide collectors with great views.

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This month in Astronomy
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Bob Berman’s strange universe
Glenn Chaple’s observing basics
Phil Harrington’s binocular universe

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