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EarthSky

Night sky from sea caves

Two images of the Milky Way, taken on the same night from sea caves along the California coastline, hundreds of miles apart.

Close-up on Cassiopeia the Queen

The constellation Cassiopeia the Queen has the distinct shape of a W or M. Find her in the north-northeast sky on September and October evenings.

Aging star blows off smoky bubble

A strikingly beautiful view of a delicate bubble of expelled material around the exotic red star U Antliae helps astronomers understand how stars evolve during the later stages of their life-cycles.

Goodbye, Cassini!

The Cassini spacecraft has become part of Saturn, the planet it studied so spectacularly and so long. Cassini’s last images and final moments, here.

September’s birthstone is the sapphire

Like the ruby, the sapphire is a form of the mineral corundum, a normally drab grey mineral.

Dark for 2 years after dino-killing asteroid?

Can you imagine a sky so laden with soot that all of Earth stayed dark for 2 years? New research suggests it happened, at the end of the age of the dinosaurs.

Astro festivals, star parties, workshops

What could be more fun on a cool, crisp autumn evening than a star party? Find a 2017 star party near you.

Orion and Sirius the Dog Star

You’ll always know it’s the sky’s brightest star, Sirius, if the very noticeable 3 stars in Orion’s Belt point to it.

Great Square of Pegasus points to Andromeda galaxy

Here’s another way to find this galaxy. Try star-hopping from the Great Square of Pegasus.

Why no eclipse every full and new moon?

In 2018, there are 13 full moons and 12 new moons, but only 5 eclipses – 2 lunar and 3 solar.