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2017’s closest supermoon is May 25

For the 1st time since 2009, a new moon – not a full moon – will be the closest and largest supermoon of a year.

Lengths of lunar months in 2017

The shortest lunar month of 2017 starts with the May 25 new moon, which is also the closest new moon of the year. Coincidence?

Star of the week: Polaris, the North Star

The entire northern sky wheels around Polaris. But it’s not the brightest star in the sky. In fact, Polaris ranks only 50th in brightness.

The story behind the 2017 eclipse stamp

A 1st-of-its-kind stamp that changes when you touch it, commemorating the August 21, 2017 total solar eclipse. Fred Espenak – whose photos are on the new stamp – tells the story.

Does Mars have a North Star?

Earth’s North Star is Polaris. It’s the star located nearly directly above Earth’s northern axis. Will future Mars explorers have a North Star to guide them?

Planet circus in May, with explanation

A beautiful spatial view of our solar system from Guy Ottewell, showing the planets’ paths along their orbits in approximately mid-May, 2017, with sightlines to them from the Earth.

Star of the week: Arcturus

Arcturus, a red giant, looks orange to the eye. It’s the brightest star on the northern half of Earth’s sky dome.

Got 5 minutes? Learn to see Saturn

June, July and August are especially good months for viewing Saturn in 2017. But you can find Saturn in May, 2017, too, especially when the moon sweeps past on May 11, 12 and 13.

Virgo? Here’s your constellation

The constellation Virgo the Maiden fully returns to the early evening sky – with her feet planted on the eastern horizon – in early May.

What are the full moon names?

Lists of common full moon names – both by month and by season – for both the Northern and Southern Hemispheres.

See it! Last night’s moon and Jupiter

They were the brightest objects nearly all night Sunday night, as seen from around the world. Here are a few photos from the EarthSky community. Thanks to all who submitted!

What’s a safe distance between us and a supernova?

And how many potentially exploding stars are located within the unsafe distance?

Can you still see Eta Aquariid meteors?

The 2017 Eta Aquariid meteor shower peaked on the mornings of May 5 and 6. But the meteor shower is active between April 19 and May 28, and this shower’s peak is broad.

Thuban is a former Pole Star

Thuban was the Pole Star some 5,000 years ago, when the Egyptians were building the pyramids.

Comet Halley’s 2 meteor showers

It’s because comets like Halley are so crumbly that we see annual meteor showers. One shower spawned by this comet is going on now. Another is visible in October.

May guide to the bright planets

Three of the 5 bright planets are easy to see: Jupiter, Saturn and Venus. Mars is obscured in western twilight. Mercury is up there, too, but veiled by eastern dawn.

Why do we celebrate May Day?

Happy May Day! A few words about this annual celebration, which has its roots in astronomy.

Hadar is a southern pointer star

Hadar, aka Beta Centauri, joins Alpha Centauri in pointing to the Southern Cross. It’s a triple system. Two of its stars will someday become nearby supernovae.

See it! Meteors, moon, Venus photos

The Lyrid meteor shower didn’t produced as many meteors as hoped, but we some lovely photos. And the moon and Venus were awesome Sunday morning!

Asteroid 2014 JO25 bigger than expected

It’s coming closer today than any asteroid this large since 2004. It came into view of small telescopes a few hours ago. Early radar observations indicate it’s bigger than we thought.