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Image via Colin Chatfield in Saskatchewan, Canada

What causes the northern lights?

They are an ethereal display of colored lights shimmering across the night sky – the aurora borealis or northern lights. What causes them?

Image via www.stoneybeckinn.co.uk

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.

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Are the December solstice and January perihelion related?

December solstice 2015 was December 22. Earth will closest to the sun in 2016 on January 2. Coincidence?

Credit: Russell Croman

Was the Christmas Star real?

A wondrous star has grown to be a major symbol of Christmas around the world. But what was it, really?

Image credit: NASA Earth Observatory

Where does noon come only once a year?

At the North and South Poles, sunrise comes at the spring equinox, noon at the summer solstice, sunset on the autumn equinox and midnight at the winter solstice.

Image Credit: Rob Lavinsky

What’s the birthstone for December?

December has two birthstones, turquoise and zircon.

NASA

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.

A supervolcano is classed as more than 500 cubic kilometers of erupted magma volume.

What triggers supervolcano eruptions?

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

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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.

Image Credit: Rob Lavinsky

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.