Good Questions: Twinkling Stars, Crackling Wood & Heatwaves

MINNEAPOLIS (WCCO) – It's Friday and that means we're answering some of your Good Questions.

Why do stars twinkle?

Gazing at the stars on a clear June night can appear magical.

"You look up and you just see these little. tiny twinkling lights," said Sarah Komperud, a planetarium educator at the Bell Museum of Natural History.

"The funny thing is, stars themselves are not actually twinkling."

Komperud says as the stars' light travels millions of miles through space and enters the Earth's atmosphere, that light's interaction with our atmosphere is what makes them appear to twinkle.

"So if you have one piece of light coming from a very distant star, it goes around and it bounces this way and that way and comes to our eyes down on the ground," Komperud said.

Why does wood crackle when it burns?

When wood is burned, it vaporizes. The vapor trapped inside the wood can exert pressure. That causes the crackles and pops.

What is the definition of a heatwave?

A heatwave means three consecutive days of 90 degree weather or higher, according to WCCO's Kylie Bearse.