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FAQs

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?

Why do most evergreen trees have a pyramid shape?

evergreen trees conifers

Photo credit: Bill Abbott/Flickr

Those who admire the shape of a Christmas tree might like to know that its shape has evolved in response to wind, snow, and light.

Why does Earth have four seasons?

Low sun at winter solstice

Low sun at winter solstice

Many believe Earth’s changing distance from the sun causes the change in the seasons. But that is not the case.

How high up are meteors when they begin to glow?

Geminid meteor. Photo by Tommy Eliassen. Capture time: 00:12am, Dec 11, 2014.  Location: Lovund, Nordland, Norway.

Geminid meteor. Photo by Tommy Eliassen. Capture time: 00:12am, Dec 11, 2014. Location: Lovund, Nordland, Norway.

Your Friday FAQ. Geminid meteor shower peaks this weekend!

I saw a flash in the night sky. What is it?

EarthSky Facebook friend Simon Waldram, in Spain, saw and photographed what looks like an iridium flare. Thank you, Simon.

Many people ask us about flashes in the night sky. They see one and want to know, what is it? Unless one of us were standing there next to you, we have no way of knowing exactly what you saw. So we can’t say for certain. But it’s possible that what you saw is a flare from an iridium communications satellite.

Why aren’t the earliest sunsets on the shortest day?

In early December, the Southern Hemisphere is approaching its summer solstice.  Sunset on that part of Earth will continue coming later until early July.  Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich QLD Australia.  Visit Phil Rettke on Facebook.

In early December, the Southern Hemisphere is approaching its summer solstice. Sunset on that part of Earth will continue coming later until early July. Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich QLD Australia.

The winter solstice is the shortest day. It offers the shortest period of daylight. But the earliest sunsets aren’t on the solstice itself. Instead, they come a couple of weeks before the winter solstice. If you’re at a temperate latitude of the Northern Hemisphere, your earliest sunsets are in early to mid-December.

Is it better to be a night owl or an early bird?

This Friday’s FAQ …Early birds versus night owls. Who wins the battle over bedtime? Let’s see what the guys at AsapSCIENCE have to say about this one. New video!

What’s the birthstone for December?

Turquoise

Turquoise

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

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.

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.”