Kelly Whitt
Artist's concept of a red giant scorching a planet.

What is the fate of the Earth?

Our Earth and sun were born together, and their fates are tied together. As our star becomes a red giant and billows outward, our planet will become a dry, scorched, uninhabitable rock. This will happen even as our Milky Way galaxy collides with the Andromeda galaxy next door.

Swirling green aurora in Alaska.

The myths behind the southern and northern lights

For millennia, humans have viewed the northern and southern lights – aurora borealis and aurora australis – and created myths and folklore to explain the dancing lights they saw in the sky.

How to find the Winter Hexagon or Winter Circle

The brightest stars in the Northern Hemisphere’s winter sky form the shape of a large hexagon, or circle, that will help you locate 6 constellations.

What are degrees, arc minutes and arc seconds?

How do skywatchers measure distances in the night sky? Here’s how to understand it when they speak of objects as being several degrees (or several arc minutes or arc seconds) apart.

Full moon behind California hills.

Photos of the last full moon of the year and decade

Photographers around the world are sharing their pics of the last full moon of 2020 and this decade, which occurred on December 29 or 30, depending on your location.

Famous Earthrise photo taken on Christmas Eve

A Christmas Eve photograph showed humans their home world from a whole new perspective. This is the photo that’s said to have launched the environmental movement. It’s “Earthrise,” the iconic photo taken by astronaut William Anders on the 4th orbit of the moon aboard Apollo 8 on December 24, 1968.

A composite of Geminid meteors on December 14, 2020.

Favorite photos of 2020’s Geminid meteor shower

EarthSky community members from around the world share their photos and experiences of this year’s Geminid meteor shower, here.

ark starry sky with two small bunches of brighter stars.

What are ‘open’ star clusters?

Open clusters are young, loosely bound gatherings of stars that may still be surrounded by the nebula – or space cloud – in which they were born. The Pleiades, Hyades, and Beehive are well-known examples of open star clusters.

Photo of star Bellatrix, with a comet sweeping near.

Bellatrix is Orion’s 3rd-brightest star

The bluish-white shoulder star, Bellatrix, aka Gamma Orionis, has a name that means “female warrior.” Bellatrix is one of the hottest stars you can see without optical aid.

The terminator separates day from night on the moon.

What is the moon’s terminator line?

The moon’s terminator is the dividing line between day and night on the moon. As we see it from Earth, it marks the line of lunar sunsets or sunrises. Earth and other worlds in our solar system have terminator lines, too.