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Larry Sessions

Pollux: The brighter Twin star

Close together in the sky, Pollux and its brother star Castor are easy to compare. Pollux is brighter and golden in color, while Castor is fainter and white.

Procyon is the Little Dog Star

The Dog Star, Sirius, is easy to spot because it’s the sky’s brightest star. Procyon – the other Dog Star – is near its brighter brother on the sky’s dome.

What is the crater-dome illusion?

When you see spacecraft images of craters on other worlds, do you sometimes think they look like domes? Here’s how to change your perception.

Castor is 6 stars in one

Castor is one of 2 bright stars in the constellation Gemini the Twins. It appears as a single star, but it’s actually a multiple star system.

Second-brightest star Canopus

Canopus is the 2nd-brightest star in the sky, and it’s easy to spot on February evenings, if …

Capella is 2 golden stars

We see Capella as the brightest star in the constellation Auriga the Charioteer. It’s actually 2 stars, each with a golden color similar to our sun.

Rigel in Orion is blue-white

Blue-white Rigel, in the constellation Orion, is one of the brightest stars in the night sky. It’s about twice as hot, and 40,000 times brighter, than our sun.

Leap second to be added December 31

Delay those New Year’s plans. World timekeepers will add a leap second just before midnight on December 31, 2016.

Aldebaran is the Bull’s fiery eye

Aldebaran – brightest star in the constellation Taurus the Bull – is huge! If it were in our sun’s place, its surface would extend almost to the orbit of Mercury.

Betelgeuse will explode someday

Someday, the star Betelgeuse will run out of fuel, collapse under its own weight, and then rebound in a spectacular supernova explosion. Someday … but probably not soon.