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What is earthshine?

When you see the crescent moon after sunset this week, notice the pale glow on its unlit portion. This glow is called earthshine.

Colors of scintillating Venus

Venus reaches inferior conjunction today, officially leaving the evening sky. It has been low in the sky, where Earth’s atmosphere has caused Venus to scintillate, or twinkle, in many colors.

Venus after sunset and before sunrise!

The planet Venus is now appearing in the west after sunset and in the east before sunrise. Don’t believe it? Astronomer Bruce McClure reports on his observation.

What is stellar magnitude?

Brightest stars to the eye are 1st magnitude, and dimmest stars to the naked eye are 6th magnitude. How the magnitude scale works in astronomy and why it’s useful.

Watch the sun’s shift on your horizon

Here’s a fun activity for the coming months. Note how far the sun moves on your horizon each day, as spring shifts toward summer (or autumn towards winter).

March equinox! Happy spring or fall

The 2017 vernal or spring (or fall) equinox occurred on March 20 at 10:29 UTC. Spring for the north – fall for the south – of Earth’s globe.

Fastest sunsets near equinoxes

We’re talking about the amount of time needed for the body of the sun to sink below the horizon. It’s true. The sun actually sets faster around the time of an equinox.

How to take great photos of star trails

When a camera captures a star’s movement across the sky, it’s called a star trail. An astrophotographer explains how he does it.

Total eclipse of sun: August 21, 2017

All you need to know about the 1st total solar eclipse visible from the contiguous U.S. since 1979, from eclipse master Fred Espenak.

Best places to watch 2017 eclipse

Here are 10 great viewing spots to watch the August 21, 2017 total solar eclipse, weather permitting.