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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.


Does eating turkey really make you sleepy?

Many believe that turkey is high in tryptophan, which causes that drowsiness you feel after a big Thanksgiving meal. True?


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.

Arctic Tern in flight via Wikimedia Commons

Which bird migrates the farthest?

Over its lifetime of about 25 years, an Arctic Tern can fly a million kilometers – nearly three times the distance from the Earth to the moon.

Screen Shot 2015-11-03 at 3.42.22 PM

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.

Sci fi concept of Dyson sphere  (Source)

What is a Dyson sphere?

What if an advanced civilization could collect all of the energy emitted by its star?