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Is Sirius the most luminous star?

To astronomers, the word “luminous” refers to a star’s intrinsic brightness. Sirius is our sky’s brightest star, but only because it’s relatively nearby at 8.6 light-years away.

Westward shift of Orion and all the stars

As Earth makes its grand tour around the sun each year, the constellations all shift westward in our sky. Orion is a good one to notice.

A mysterious star called Epsilon Aurigae

Epsilon Aurigae’s light dims for a period of about 2 years, in a 27-year cycle. The star’s last dimming was from 2009 to 2011.

Use Big Dipper to find Little Dipper

The Big Dipper is easy to recognize, but the Little Dipper … not so much. Here’s a tip that can help.

Use Big Dipper to find North Star

The 2 outer stars in the Big Dipper’s bowl point to the North Star, aka Polaris.

See the zodiacal light

The moon is waning again, leaving the sky dark in early evening. Watch for the mysterious zodiacal light in the west after true darkness falls. Southern Hemisphere? Look east before dawn.

Top 4 keys to mastering moon phases

The most important key is to think of the moon as a world in space, with a day and night side.

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.

Moon in Taurus February 22 and 23

Tonight and tomorrow night, let the moon show you the constellation Taurus the Bull on the great dome of sky. How to recognize the Bull’s 2 most prominent features, here.

Arc to Arcturus, the springtime star

Before going to bed tonight, locate the Big Dipper in your northern sky, and then follow the arc in the Dipper’s handle to find yellow-orange star Arcturus.

Hare and Dove at Orion’s feet

Lepus the Hare and Columba the Dove are 2 faint constellations near the easy-to-find constellation Orion. You need a dark sky to see them.

Blue-white Rigel at Orion’s foot

Rigel is far, some 775 light-years away. It must be extraordinarily luminous to be so distant yet shine so brightly in our sky.

See the Double Cluster in Perseus

First, find the M- or W-shaped constellation Cassiopeia. The Double Cluster – 2 open star clusters – is nearby and beautiful in a dark sky.

Big Dipper stars point to North Star

The two outermost stars in the bowl of the Big Dipper always point to the North Star, aka Polaris. That’s why astronomers call these stars The Pointers.

Groundhog Day has roots in astronomy

Groundhog Day is tied to the movement of Earth around the sun. It’s the year’s 1st cross-quarter day.

Zodiacal light glowing pyramid after dark

From the Northern Hemisphere, look for the elusive zodiacal light, a hazy pyramid of light extending up from the sunset point. Southern Hemisphere? Look before dawn!

Moon near Castor and Pollux January 29

Castor and Pollux – brightest stars in the constellation Gemini the Twins – are noticeable for being bright and close together on the sky’s dome.

Identify stars in the Winter Circle

Go outside, and look for the waxing gibbous moon tonight. Then notice the stars nearby. Tonight’s moon is within the Winter Circle stars.

Hyades star cluster: Face of Taurus

The bright star Aldebaran is part of a V-shaped pattern of stars called the Hyades. This easy-to-find star cluster represents the face of Taurus the Bull.

Moon near Aldebaran January 26 and 27

Will you see Aldebaran in the moon’s glare on January 26 or 27, 2018? Plus … the story of Aldebaran when it was part of a double pole star.