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Why observe Earth Day on April 22?

April 22 is the date of Earth Day in part because of Arbor Day, an earlier observance. The focus of Earth Day 2018 is plastic pollution.

Impossibly starry skies over NYC

This week is International Dark Sky Week. Celebrate by watching this impossible, but magical, video of dark, starry skies over light-polluted New York City. It’s new from Project Skyglow.

Theorists describe black hole megamergers

“Binary black holes are basically like giant targets hanging out in a globular star cluster, and as you throw other black holes or stars at them, they undergo these crazy chaotic encounters.”

Tour the moon in 4K

Take a virtual tour of the moon in all-new 4K resolution – Ultra High Def – created from data provided by NASA’s Lunar Reconnaissance Orbiter spacecraft.

Cosmic cold front older than solar system

Astronomers were surprised to discover an enormous “cold front” millions of light years in extent and older than the solar system.

Earth’s magnetosphere envelops and protects us

A giant bubble of magnetism protects us from the sun’s fury. Take 3 minutes to learn about it, in this new NASA ScienceCast video.

Watch a robot fish swim in the ocean

MIT computer scientists have developed SoFi – a soft, robot fish made of silicone rubber – that can swim alongside real fish in the ocean.

The amazing feathers of an outlandish bird

The super-black feathers of Birds of Paradise absorb almost every last bit of light that strikes them. This black is so dark your eyes can’t focus on its surface.

Arctic winter sea ice extent 2nd lowest

Sea ice in the Arctic grew to its annual maximum extent last week, and joined 2015, 2016 and 2017 as the 4 lowest maximum extents on record, say scientists

Great Pacific Garbage Patch now 3 times size of France

In 2015, a mega-expedition – 30 vessels simultaneously – crossed the Great Pacific Garbage Patch and collected 1.2 million plastic samples. They say the problem is getting worse.