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EarthSky

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.

How many stars can you see?

It takes up to 30 minutes for your eyes to adapt to the dark. And a country location is best. Then, on a clear night with no moon … how many stars?

What’s the most distant human object from Earth?

The most distant human object is now over 13 billion miles (21 billion km) from Earth.

Chinese New Year on February 15-16

The 2018 Chinese New Year – which coincides with the February new moon – starts February 16 in Asia (February 15 in the west) and rings in the Year of the Dog.

Today is Chuck Yeager’s 95th birthday

Chuck Yeager, first pilot to break the sound barrier, personified what it meant to have “the right stuff.”

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.

Somber Betelgeuse in Orion’s shoulder

Betelgeuse’s red color indicates a star well into the autumn of its years. In fact, the star is a magnificently rare red supergiant.

What is radiocarbon dating?

At a very steady rate, unstable carbon-14 gradually decays to carbon-12. The ratio of these carbon isotopes reveals the ages of some of Earth’s oldest inhabitants.

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.