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EarthSky

Deneb, tail of Cygnus the Swan

Deneb marks the Tail of Cynus the Swan … and the head of a crosslike pattern known as the Northern Cross.

NASA camera views sunglint from Earth

You’d expect sunglint from an ocean or other body of water. But the camera caught some glints over land as well. A new NASA video explains how scientists solved the mystery.

Lake Baikal: Earth’s deepest, oldest lake

Controversy surrounds construction of hydropower stations on a river that feeds deep, ancient Lake Baikal.

What are the full moon names?

Lists of common full moon names – both by month and by season – for both the Northern and Southern Hemispheres.

What’s a safe distance between us and a supernova?

And how many potentially exploding stars are located within the unsafe distance?

What’s the birthstone for May?

Happy birthday May babies! Your birthstone, the emerald, is a type of beryl colored green by chromium. Perfect emeralds are among the rarest of gemstones.

Why birds smash into windows

Up to 1 billion birds die each year in the U.S. due to collisions with windows. Why do birds slam into windows, and what can you do to prevent it?

Favorite photos for Earth Day 2017

Here’s a collection of lovely, gorgeous, and wonderful photos from the EarthSky community in celebration of our favorite planet. Thank you all!

Cassini to begin its Grand Finale

The glorious Cassini spacecraft – now nearly out of fuel – will make the 1st in a daring series of dives through the gap between Saturn and its rings on April 26.

What is a glory?

People traveling in airplanes often see glories. The sun has to be behind your head. You’ll see the plane’s shadow cast on a cloud, surrounded by a halo of light.