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You can’t walk on these cloud streets

Cloud streets are long rows of cumulus clouds oriented parallel to the direction of the wind. Check out these cool images!

What is a coronal mass ejection?

Want to brush up on your knowledge about these solar hiccups – CMEs, for short – that can ripple through our solar system and can interrupt satellites and power grids on Earth?

What is a sun pillar, or light pillar?

Sun pillars, or light pillars, are shafts of light extending from the sun or other bright light source. They’re caused by ice crystals drifting in Earth’s air.

How much moon do we see?

One side of the moon always faces Earth. Even so, over time, it’s possible to see as much as 59% of the moon’s surface, due to lunar libration.

Born in June? Here’s your birthstone

Happy birthday June babies! Your month has 3 birthstones – pearl, moonstone, and Alexandrite.

What’s the birthstone for May?

Happy birthday May babies! Your birthstone, the emerald, is a type of beryl colored green by chromium. Perfect emeralds are among the rarest of gemstones.

Born in March? Here’s your birthstone

Happy birthday to all you March babies. Your month has 2 birthstones – the aquamarine and the bloodstone.

Star brightness versus star luminosity

Some extremely large and hot stars blaze away with the luminosity of a million suns! But other stars look bright only because they’re near Earth.

What’s a penumbral eclipse of the moon?

During a penumbral eclipse, observant people in the right spot on Earth will look up and notice a dark shading on the moon’s face. Others look and notice nothing at all.

What’s a Blood Moon?

Nowadays, 4 totally eclipsed moons in a row are called Blood Moons. Why? We don’t know for sure, but the answer may lie in a 2013 book by 2 Christian pastors.

Circumpolar stars never rise or set

From Earth’s North and South Poles, all the stars appear as circumpolar. Meanwhile, at the equator, no star is circumpolar. And what about in between?

How big are the biggest monster stars?

How big can stars get? And how do these monster stars get so big?

What are the seasons like on Uranus?

Uranus lies nearly sideways with respect to the plane of its orbit around the sun. That sideways tilt makes a huge difference between winter-summer on Uranus, and autumn-spring.

January’s birthstone is the garnet

Happy birthday January babies!  Your birthstone is the garnet.

Lucky New Year’s foods

Lucky New Year’s foods in the U.S. South and around the world. Happy 2017!

Why were prehistoric insects so huge?

Before the dinosaurs, giant insects ruled the world more than 300 million years ago.

How long to orbit Milky Way’s center?

One journey of our sun and planets around the center of our Milky Way galaxy is sometimes called a cosmic year. That’s approximately 225-250 million Earth-years.

Why a halo around the sun or moon?

A large ring or circle of light around the sun or moon is called a 22-degree halo by scientists.

What is the Brocken Spectre?

The Brocken Spectre is your own shadow, cast on mists below you, when you are mountain climbing. The shadow may appear enormous and has a ring around it.

What causes rainbow colors in clouds?

Iridescent clouds – clouds with rainbow colors – happen when especially tiny water droplets or small ice crystals individually scatter light.