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Do we all see the same moon phase?

One Earth. One sky. One moon phase (more or less) from all of Earth. So why (and how) does the moon look different from different parts of Earth?

Mars brighter in 2018 than since 2003

Mars is getting brighter. By mid-2018, Mars will be at its brightest since 2003, when it was closer and brighter in our sky than in some 60,000 years.

Lyrid meteor shower: All you need to know

In 2018, April 22 is the peak morning. The moon, near the 1st quarter phase, is out of the way. Expect 10 to 20 meteors per hour at the peak.

Find the Lyrid meteors’ radiant point

You don’t need to find the radiant to see the meteors. But it’s fun to spot, near the bright star Vega.

April 21 is Astronomy Day

A beautiful chart from astronomer Guy Ottewell, showing the evening sky on Astronomy Day 2018. Plus links to Astronomy Day events and other info.

How the moon reveals the sun’s mass

How do astronomers determine masses for distant space objects? Here’s one example – using the moon’s orbit as a baseline to find the mass of our sun – from EarthSky’s Bruce McClure.

Come to know the Big and Little Dippers

The Big Dipper is easy. And, once you find it, you can find the Little Dipper, too.

April guide to the bright planets

Venus blazes away in the west at evening twilight. Jupiter rises at mid-to-late evening and shines brightly before dawn. After the Mars and Saturn conjunction on April 2, the pair can be seen all month before dawn, near one another.

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.

How many stars can you see?

It takes up to 30 minutes for your eyes to adapt to the dark. And a country location is best. Then, on a clear night with no moon … how many stars?

Taurus? Here’s your constellation

How to find to find the constellation Taurus in your night sky. Plus the names of some of its bright stars and star clusters and its mythology.