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What is time?

… And why does it move forward?

See 5 bright planets at once

First time we can see 5 planets at once since 2005. All 5 are up before dawn, still, and all 5 will remain visible until Mercury disappears in the dawn just after mid-February.

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?

When does the Age of Aquarius begin?

Age of Aquarius begins when vernal equinox point moves out of constellation Pisces and into Aquarius. There’s no definitive answer as to when that will be.

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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.