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Awesome Geminid shower in 2017? Thank 3200 Phaethon

This mysterious rock-comet is the parent body of the Geminid meteor shower and the likely reason the Geminids were so strong in 2017. The rock-comet itself is closest to Earth December 16.

Lengths of lunar months in 2017

Longest lunar month of 21st century (2001 to 2100) starts with December 18 new moon. It’s also the farthest new moon of the year. Coincidence?

Sirius in many colors

When you see the sky’s brightest star – Sirius – low in the sky, you’re seeing it shine through an extra thickness of Earth’s atmosphere. At such times, its colorful flashing might surprise you.

Solstice coming up December 21

December solstice 2017 arrives on December 21 at 16:28 UTC. High summer for the Southern Hemisphere. For the Northern Hemisphere, the return of more sunlight!

Star of the week: Mirfak

Mirfak isn’t as famous as Algol, its brother star in the constellation Perseus. But Mirfak is easier to find and can help guide you to Algol.

How to see rock-comet 3200 Phaethon

You can’t see 3200 Phaethon – parent of the Geminid meteor shower and a strange asteroid-comet hybrid – with the eye alone. But backyard telescopes can pick it up. Charts and more here.

Don’t miss the Geminids in 2017!

The Geminid meteor shower is always reliable, but might be extra special in 2017. Peak morning is likely December 14. Be sure to watch for the moon near the morning planets!

Find the Geminid meteors’ radiant point

December’s Geminid meteor shower radiates from the constellation Gemini the Twins. To see it, look east in mid-evening or overhead by about 2 a.m.

Why brighter stars at this time of year?

No matter where you are on Earth on December, January and February evenings, you’re looking toward bright stars in our local spiral arm.

Menkar is the Whale’s alpha star

It’s not the most famous star in Cetus the Whale, or the brightest, although it carries the designation Alpha. But Menkar has its own claims to fame.

EarthSky’s 2017 meteor shower guide

A highlight of the meteor-watching year is just ahead. The Geminid meteor shower rivals the August Perseids and, in 2017, has little to no interference from the moon.

December guide to the bright planets

Of the 5 bright planets, Mars and Jupiter appear in the December 2017 predawn sky all month. Mercury joins them around the December solstice. Venus and Saturn will become lost in the sun’s glare this month.

When is the next Blue Moon?

Blue-colored moons are rare. But folklore has defined 2 other sorts of Blue Moons, which are more commonly seen. The next one will be on January 31, 2018.

When is my earliest sunset?

At the latitude of Miami, Florida or Brownsville, Texas in the U.S. – or, say, the city of Naha in Okinawa, Japan – the earliest sunsets of the year are happening now. How earliest sunset varies with latitude, but always comes before the winter solstice.

Aries? Here’s your constellation

How to see Aries the Ram in your night sky, plus info about this constellation in astronomy history and mythology.

Astro festivals, star parties, workshops

The wintertime star parties are mostly at southerly latitudes. Time to plan a winter vacation!

Say farewell to Venus

Did you see the conjunction of Venus and Jupiter before sunup around November 13? Since then, Jupiter has been climbing away from the sunrise, while Venus has been falling toward it.

Hamal is an ancient equinox star

Hamal is the brightest star in Aries the Ram. How to find it in your sky.

Messier 33: 2nd-closest spiral galaxy

Triangulum galaxy, aka Messier 33. is 2.7 million light-years away, and the 3rd-largest member of our Local Group, after the Milky Way and Andromeda galaxies.

How to see the Great Square of Pegasus

It’s easy! The Great Square of Pegasus consists of 4 stars of nearly equal brightness in a large square pattern. Once you find it, you can star-hop to other well-known sights in the sky.