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FAQs

Where does noon come only once a year?

Yes, at the Earth’s South Pole, high noon comes only once a year, on the December summer solstice. Yet, it’s midnight at the other end of the world – at the Earth’s North Pole – where midnight only comes once a year, on the December winter solstice.

What is the Ring of Fire?

A September 2010 eruption of Mount Yasur in Vanuatu. Image appears courtesy of Tom Pfeiffer/ Volcano Discovery.

There are more than 450 active and dormant volcanoes located within the Ring of Fire. Plus it’s prone to powerful earthquakes. Here’s why.

How to spot the International Space Station

ISS crossing the sky in a long-exposure photograph by Antonín Hušek?.

ISS crossing the sky in a long-exposure photograph by Antonín Hušek?.

Every so often, the International Space Station (ISS) becomes visible in your night sky. It’ll look like a bright star moving quickly above the horizon. The ISS is so bright, it can even been seen from the center of a city. Here’s how you can spot the ISS in your night sky.

What’s the birthstone for December?

Turquoise

Turquoise

Happy birthday to all our December-baby friends! December has two birthstones, turquoise and zircon.

How far is a light-year?

The Orion Nebula, 1,500 light years from Earth. Image credit: NASA/JPL-Caltech/STScI

The Orion Nebula, 1,500 light years from Earth. Image credit: NASA/JPL-Caltech/STScI


Here’s your FAQ for this Friday ….

Light is the fastest-moving stuff in the universe. It travels at an incredible 300,000 kilometers (186,000 miles) per second. That’s very fast. A light-year is the distance light travels in one year. How far is that?

Does eating turkey really make you sleepy?

Photo credit: Lotus Carroll/Flickr

Photo credit: Lotus Carroll/Flickr

Ah, Thanksgiving Day. You pile your plates with turkey, dressing, two kinds of potatoes, cranberries – all the traditional foods – and dig in. Second helpings? Of course! An hour later, after plenty of food and conversation, you push back and notice you’ve become very, very sleepy. You think, “I’m sleepy because turkey is high in tryptophan.”

Is it true that Jupiter protects Earth?

Brown spots mark the places where fragments of Comet Shoemaker-Levy 9 tore through Jupiter's atmosphere in July 1994.  Image and caption via Wikimedia Commons.

Brown spots mark the places where fragments of Comet Shoemaker-Levy 9 tore through Jupiter’s atmosphere in July 1994.

Here’s a question we get regularly:

Is it true that Jupiter could be considered our friendliest planet because – without Jupiter – comets would be more likely to hit us?

The answer is yes … and no.

What makes a halo around the sun or moon?

A moon halo in Mandan, North Dakota by Marshall Lipp. February, 2015.

A moon halo in Mandan, North Dakota by Marshall Lipp. February, 2015.

Your Friday FAQ! Here’s what causes those rings of light around the sun or moon … plus lots of cool photos.

What triggers supervolcano eruptions?

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

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

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

Which bird migrates the farthest?

Arctic Tern in flight via Wikimedia Commons

via Wikimedia Commons

Friday FAQ! Over its lifetime of about 25 years, this bird can fly a million kilometers – nearly three times the distance from the Earth to the moon. What is it?