FAQs

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May 17, 2012 Space

What makes a halo around the sun or moon?

Halos around the moon – or sun – are a sign of thin cirrus clouds drifting high above our heads.

Astronomy Without Border eclipse glasses.  Image via Dionne Bunsha.
May 16, 2012 Space 6 Comments

What’s the best way to view a solar eclipse safely?

Next solar eclipse is an annular or ring eclipse on May 20-21. There’s also the transit of Venus on June 5-6. You’ll need solar filters, or indirect viewing method.

Image Credit: Rob Lavinsky
May 01, 2012 Earth 2 Comments

What’s the birthstone for May?

People in the Middle Ages believed that May’s birthstone, the emerald, held the power to foretell the future.

Via moonsmuses.com
May 01, 2012 Human World 8 Comments

Why do we celebrate May Day?

Happy May Day! A few words about this annual celebration, whose roots are in astronomy.

Image Credit: NASA
Apr 19, 2012 Space 6 Comments

How high up are meteors when they begin to glow?

Meteors begin to “glow” almost as soon as they hit Earth’s atmosphere, but tend to vaporize (burn up completely) at varying altitudes.

Photo credit: Robbo-Man
Apr 17, 2012 Space 10 Comments

What is earthshine?

That glow over the unlit part of a crescent moon – called earthshine – is light reflected from Earth.

Photo Credit: wili hybrid
Apr 11, 2012 Earth 2 Comments

What gives rainbows their curved shape?

Sunlight that shines into a raindrop leaves that raindrop at an angle of 138 degrees from the path that the light traveled before it entered the drop.

Image courtesy Tim Haynes
Apr 05, 2012 Space 3 Comments

Why does the sun look red at sunset?

When we look toward a horizon, we’re looking through more atmosphere than when we look overhead. That’s why you see red sunsets.

Image Credit: USGS
Apr 02, 2012 Earth Leave a comment

What’s the birthstone for April?

April’s birthstone, the diamond, is a symbol of enduring love.

March 3, 2012
Mar 15, 2012 Space 9 Comments

Why is Mars sometimes bright and sometimes faint?

The brightness of Mars in our sky depends on where our two planets are in orbit around the sun.