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2018’s 2nd Blue Moon on March 31

The March 31 Blue Moon is the 2nd Blue Moon of 2018. We haven’t had 2 Blue Moons in a year since 1999 and won’t again until 2037.

Why is Easter so early this year?

Yes, April 1 is an early Easter, but 2018 doesn’t hold a record for the earliest possible Easter. How the date of Easter is determined, here.

Mizar and Alcor, famous double star

Mizar and its fainter companion star Alcor are easy to spot in the Big Dipper’s handle.

March equinox: All you need to know

Happy equinox! The March 20, 2018, equinox is an event that happens on our sky’s dome and a seasonal marker in Earth’s orbit around the sun.

Are day and night equal at the equinox?

Equinox means “equal night.” And you might hear day and night are equal at the equinoxes. Yet Earth’s air and our sun conspire to give us more daylight at an equinox.

See it! Young moon, Venus, Mercury

Wow! So many of you are catching the moon, Venus and Mercury after sunset. Thank you for all your photos. We wish we could post them all!

The Beehive: 1,000 stars in Cancer

On a dark night, look for it as a smudge of light, with 3 times the moon’s diameter. It’s really a wondrous cluster of stars called the Beehive, or M44.

See the early morning Milky Way

The edgewise view into our own galaxy, looking toward the galaxy’s heart, from EarthSky community members who ventured into the cold and darkness before dawn in February 2018.

See it! 1st March full moon

Photos from the EarthSky community of the March 1-2, 2018, full moon, the 1st of 2 full moons for this month!

What are star trails, and how can I capture them?

When a camera captures a star’s movement across the sky, it’s called a star trail. An astrophotographer explains how he does it.