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How do snowflakes get their shape?

Depending on the temperature and humidity of the air where the snowflakes form, the resulting ice crystals will grow into a myriad of different shapes.

What’s a safe distance between us and an exploding star?

And how many potential supernovae are located within the unsafe distance?

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What are cloud streets?

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

What is Lunar X?

Alien visitation? No. Lunar X is an example of how lighting and topography can combine to produce a pattern that seems familiar to the human eye.

Why does the new year begin on January 1?

New Year’s Day is a civil event. Its date isn’t precisely fixed by any natural seasonal marker.

What’s the birthstone for December?

December has two birthstones, turquoise and zircon.

Is it true that Jupiter protects Earth?

Jupiter’s gravity slings long-period comets out of harm’s way, while nudging some asteroids closer to Earth. And, in 1770, Jupiter took aim on Earth – but missed.

What triggers supervolcano eruptions?

Supervolcanoes – massive eruptions with potential global consequences – don’t appear to follow the conventional volcano mechanics, say researchers.

What is El Niño?

A big El Niño is developing in 2015, say scientists. This NASA video explains El Niño and its impact on the marine food web.

What’s the birthstone for November?

November’s birthstone, the topaz, was thought to have the power to cool boiling water, as well as excessive anger.