Enjoying EarthSky? Subscribe.

263,548 subscribers and counting ...


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.

See it! Super Blue Moon eclipse photos

It was a Blue Moon, a supermoon and a moon in total eclipse. EarthSky community members around the world came through as always with awesome photos.

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.

Contemplate the apex of the sun’s way

Our sun moves around the center of the galaxy, toward the star Vega. Astronomers call this motion the apex of the sun’s way. One circuit – about 230 million years – is called a cosmic year.

A winding river of stars called Eridanus

Why search for such a faint constellation? Only because it’s very beautiful. Plus seeing Eridanus can give you a kinship with stargazers from centuries ago.