Why are stars so bright on winter nights?

In December, January and February, we look away from the Milky Way's cloudy core toward the Orion spiral arm, with stars so bright they capture our attention.

Mercury was farthest from the sunrise December 25

Mercury reached its greatest elongation - greatest distance from the sunrise - on December 25, 2024. Look east at dawn. It'll disappear from the morning sky in January.

Longest days accompany the December solstice

The longest days accompany the winter solstice. In December, a day - a whole cycle of day and night - is about half a minute longer than the average 24 hours.

What does opposition mean for an outer planet?

Opposition is when Earth passes directly between the sun and an outer planet, placing the outer planet on the opposite side of the sky from the sun.

Meteors in moonlight: 6 tips for when the moon is out

Meteors in moonlight. It's not optimal, but it happens! Here's six tips to improve your chances of seeing meteors even when a bright moon is lighting up the sky.

Mysterious 3200 Phaethon: Parent to the Geminids

3200 Phaethon is the weird comet-like asteroid that spawns the Geminid meteor shower. New research reveals more answers ... and questions.

Thinking of buying a telescope? Read these tips 1st

Are you thinking of buying a telescope? Here's how to know if you're ready, with tips on what 1st-time buyers should look for.

Retrograde motion for Mars starts today

The red planet Mars will start its retrograde motion on December 7, 2024. It'll pause briefly in front of the stars, and then begin moving westward.

Meteor showers are here: Top 10 tips for watching

Meteor showers are unpredictable but nothing beats them for a fun and relaxing time under the stars. Here's our 10 tips to maximize your meteor viewing time.

Comets are icy balls of gas, dust and rock

Comets are diffuse balls of ice and dust orbiting the sun. They're sometimes visible in our skies. A comet's tail can stretch millions of miles across space.