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How big are the biggest monster stars?

How big can stars get? And how do these monster stars get so big?

What are the seasons like on Uranus?

Uranus lies nearly sideways with respect to the plane of its orbit around the sun. That sideways tilt makes a huge difference between winter-summer on Uranus, and autumn-spring.

Why stars seem brighter 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.

January’s birthstone is the garnet

Happy birthday January babies!  Your birthstone is the garnet.

Lucky New Year’s foods

Lucky New Year’s foods in the U.S. South and around the world. Happy 2017!

Why were prehistoric insects so huge?

Before the dinosaurs, giant insects ruled the world more than 300 million years ago.

Watch for earliest sunsets before solstice

Year’s shortest day comes at winter solstice. But, for Northern Hemisphere, earliest sunsets happen around early December. Southern Hemisphere? Your earliest sunrises are around now.

How long to orbit Milky Way’s center?

One journey of our sun and planets around the center of our Milky Way galaxy is sometimes called a cosmic year. That’s approximately 225-250 million Earth-years.

Why a halo around the sun or moon?

A large ring or circle of light around the sun or moon is called a 22-degree halo by scientists.

What is the Brocken Spectre?

The Brocken Spectre is your own shadow, cast on mists below you, when you are mountain climbing. The shadow may appear enormous and has a ring around it.