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Watch Thursday’s spacewalk

Two ISS astronauts will be outside the space station beginning about 8 a.m. EDT (12:00 UTC) on March 30. The spacewalk is expected to last about 6.5 hours. Links to live viewing here.

Watch SpaceX rocket launch Thursday

The launch window for the reused – “flight proven” – Falcon 9 rocket opens at 18:27 EDT (22:27 UTC) on March 30. There’s a two-and-a-half-hour launch window. Links to the live launch here.

What is a Dyson sphere?

Are some advanced civilizations in our galaxy now collecting all of the energy emitted by their stars? If so, we would call their energy-collecting megastructures Dyson spheres.

Watch a full rotation of the moon

Wonderful video from the Lunar Reconnaissance Orbiter, a NASA spacecraft in a polar orbit around the moon since 2009. The moon as you’ve never seen it!

Today in science: Great Alaska earthquake

The earthquake – centered in Prince William Sound off the coast of south-central Alaska – was the most powerful yet recorded in North America at magnitude 9.2.

Another Planet 9 search! You can help

This one will use images of the sky visible from Earth’s Southern Hemisphere. You can help from anyplace on the globe. The search is for a 9th major planet in our system, nicknamed Planet 9.

7 Earth-sized worlds? What we really see

A reality check from astrophysicist Brian Koberlein on what we actually see of the 7 recently discovered Earth-sized planets orbiting the star TRAPPIST-1.

A Chinese perspective on spring

In Chinese thought, spring is associated with the direction east, the sunrise direction as Earth spins us toward the beginning of each new day.

Bodies freed from gravity’s grip

Life on Earth is used to gravity. So what happens to our cells and tissues in space?

Moon shadow path in 2017 solar eclipse

Fly along with the moon’s shadow in this NASA video depicting the path of the August 21, 2017 total eclipse of the sun.