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Why rainbows are curved

A rainbow isn’t a flat 2-dimensional image on the dome of sky. It’s more like a mosaic, composed of many separate bits … in 3 dimensions.

Follow the arc to Arcturus, and drive a spike to Spica

If you only ever learn one star mnemonic, make it this one!

Top 10 things about brown recluse spiders

It’s their active season. Here are some things you might not know.

Use the Big Dipper to find the Little Dipper

Polaris – aka the North Star – marks the end of the Little Dipper’s handle. The 2 outer stars in the bowl of the Big Dipper always point to Polaris.

Find Vincent van Gogh’s Big Dipper

Here’s an easy astronomy lesson, from a master in the art of loving nature.

Why beware the Ides of March?

The Ides of March are March 15. We in modern times probably wouldn’t know about them, if it weren’t for William Shakespeare.

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.