Yarkovsky effect: Pushing asteroids with sunlight

The Yarkovsky effect is a minuscule push on a small body in space, imparted by nothing more than sunlight. It can change the direction of asteroids.

Learn how to shoot photos of meteors

Want to shoot photos of meteors with your camera? The first step is planning. The next step is to gather your equipment. Then on to the capture process.

How far is a light-year? Plus, distances in space

How can we comprehend the distances to the stars and other galaxies? Here's a way to understand a light-year in terms miles and kilometers.

What’s a Blood Moon? All you need to know

By this definition, Blood Moon is a member of a special kind of lunar tetrad : four total lunar eclipses in a row. Now it's used for any total lunar eclipse.

Earthshine is a lovely glow on the unlit portion of the moon

Earthshine - the dim glow on the darkened portion of a crescent moon - is light from Earth cast on the night side of the moon. Watch for it around the new moon.

Radiant point of meteor showers: All you need to know

Meteors enter Earth's atmosphere on parallel paths. So, you'll see meteors appear to come from a single point in the sky: the radiant point!

Why is there no eclipse every full and new moon?

If the moon orbited Earth on the same plane that Earth circles the sun, we'd have an eclipse at every full and new moon. Here's why we don't.

Greatest elongation, superior and inferior conjunction

When Mercury and Venus are as far from the sun as they get from our earthly point of view, they are at greatest elongation. It is the best time to observe them.

The moon illusion makes the moon look huge!

When you see a large-looking moon low in the sky, does the moon look bigger to you? That's the moon illusion that makes the moon look so big.

What is stellar magnitude?

The brightest stars to the eye are 1st magnitude, and dimmest stars to the eye are 6th magnitude. How does stellar magnitude work in astronomy?