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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.


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.


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.