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Why do fireflies light up?

“Fireflies on top of the wave of grass and overflowing. Biggest firefly show in years.” by Eileen Claffey, June, 2015.

Fireflies are sometimes called lightning bugs. Many a child has spent a summer evening chasing them. And maybe you’ve wondered – how and why are these insects able to light up?

Measuring sea level on a dynamic Earth

Image credit: Wally Gobetz

Image credit: Wally Gobetz

Warming temps, and the rise and fall of coasts, complicate measurements of sea level. How do scientists establish sea level on a constantly changing Earth?

How much do oceans add to world’s oxygen?

Phytoplankton - the foundation of the oceanic food chain. image via NOAA

Phytoplankton – the foundation of the oceanic food chain. Scientists estimate that phytoplankton contribute between 50 to 85 percent of the oxygen in Earth’s atmosphere. Image via NOAA

Scientists agree that there’s oxygen from ocean plants in every breath we take.

How do hurricanes get their names?


Astronaut Ed Lu captured this view of Hurricane Isabel in 2003 from the International Space Station. Image via Mike Trenchard, NASA.

Ever wonder how hurricanes get their names? And why do hurricanes have names at all? Meteorologists long ago learned that naming tropical storms and hurricanes helps people remember the storms, communicate about them more effectively, and so stay safer if and when a particular storm strikes a coast. Find out more about hurricane names inside.

What’s the birthstone for June?

Photo credit: Valentyn Volkov/Shutterstock

Photo credit: Valentyn Volkov/Shutterstock

Happy birthday to all our June baby friends! Your month has three traditional birthstones – pearl, moonstone, and alexandrite.

What is a coronal mass ejection or CME?

Aug 2012 CME

Aug 2012 CME

Every so often, the sun burps with the power of 20 million nuclear bombs.  These hiccups are known as coronal mass ejections (CMEs)—powerful eruptions near the surface of the sun driven by kinks in the solar magnetic field.  The resulting shocks ripple through the solar system and can interrupt satellites and power grids on Earth. During a CME, enormous bubbles of superheated gas—called plasma—are ejected from the sun.  Over the course of several hours, one billion tons of material are lifted off the sun’s surface and accelerated to speeds of one million miles per hour.  This can happen several times a day when the sun is most active.

Does the North Star ever move?

Sky wheeling around Polaris, the North Star.

Sky wheeling around Polaris, the North Star.

Polaris – the North Star – is like the hub of a wheel. It doesn’t rise or set – instead, it appears to stay put in the northern sky.

Scared of thunder and lightning? You have astraphobia

Never let your pets watch scary movies. Never a good idea! Image Credit: John Veldboom via Flickr

Thunder and lightning can be scary to pets, too. Image via John Veldboom via Flickr

Bam! Yikes!

Do you – and your dog – have astraphobia?

I saw a flash in the night sky. What is it?

Nature & Man: Iridium Flare, Milky Way, Clouds and Light Pollution by Mike Taylor.  Visit Mike Taylor Photography.

Iridium flare by Mike Taylor Photography.

Many people ask us about flashes in the night sky. They see one and want to know, what is it? Unless one of us were standing there next to you, we have no way of knowing exactly what you saw. So we can’t say for certain. But it’s possible that what you saw is a flare from an iridium communications satellite.

What is a dwarf planet?

You’ll know in 60 seconds. New Space Shorts video from NASA