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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 earthshine?

When you see the crescent moon after sunset this week, notice the pale glow on its unlit portion. This glow is called earthshine.

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!

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.

Super halos around very young galaxies

Astronomers directly observed a pair of Milky-Way-like galaxies, seen when the universe was 8% of its current age. They were excited to find the young galaxies surrounded by huge halos.

New map of space dust in 3-D

Sure, we’re all collections of space dust. But astronomers also want to study it in order to understand how space dust in our Milky Way obscures starlight from afar.

Does Mars sometimes have rings?

It’s possible that Mars’ closer moon – Phobos – might alternate between becoming a planetary ring and clumping together to form a moon.

Star’s death spiral into black hole

What happens when a star with about our sun’s mass spirals into a black hole? With the distant event known as ASASSN-14li, astronomers have figured out some details.