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Supermoons of 2016

What most call a Blue Moon isn't blue in color. It's only Blue in name. This great moon photo from EarthSky Facebook friend Rebecca Lacey in Cambridge, Idaho.

Moon photo is from Rebecca Lacey in Cambridge, Idaho.

According to the definition of supermoon coined by Nolle, the year 2016 has a total of six supermoons. The new moons of March, April and May and the full moons of October, November and December all qualify as supermoons. Follow the links inside to learn about the supermoons of 2016.

Why does the new year begin on January 1?

Photo credit: Daniel Moile

The date of New Year’s Day seems so fundamental that it’s almost as though nature ordained it. But New Year’s Day is a civil event. Its date is not precisely fixed by a seasonal marker.

Are the December solstice and January perihelion related?

Earth and sun via ISS Expedition 13 / NASA.

Earth and sun via ISS Expedition 13 / NASA.

Earth comes closest to the sun (perihelion) on today. Meanwhile, the December solstice took place on December 22. Are the December solstice and January perihelion related? No. It’s just a coincidence that they come so close together. Click inside to see when perihelion will fall at the March equinox.

Was the Christmas Star real?

What was the Christmas Star? Scientist Bradley Schaefer has some new things to say on this week’s EarthSky 22. Photo by Russell Croman

The Star of Bethlehem, or Christmas Star, is mentioned in the Bible. It’s said to have led the three wise men to Bethlehem. But was the Christmas Star a real object in the sky? Or was it just a symbol?

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.”