Enjoying EarthSky? Subscribe.

121,360 subscribers and counting ...

FAQs

Why do we scream?

Despite our fascination with screams, science knows relatively little about them.

Harold Gouzoules is one of the few scientists researching human screams. He collects them and analyzes their tone, pitch, and frequency to try and uncover the hidden patterns and complexities carried in one of the most intense human sounds.

When is the next supermoon?

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 Richard Nolle 30 years ago, the year 2015 has a total of six supermoons. They are the new moons of January, February and March and the full moons of August, September and October. The September 28, 2015 full moon will be the closest supermoon of 2015. It’ll also undergo a total lunar eclipse! Follow the links inside to learn about the supermoons of 2015.

When can you see Earth’s shadow?

Night falls when the part of Earth you’re standing on enters Earth’s shadow. Click here to expand this image. Image via NASA

At yesterday’s solar eclipse, the moon’s shadow brushed Earth. But what about Earth’s shadow? You can see it any clear evening. Just like you or me, Earth casts a shadow. Earth’s shadow extends millions of miles into space, in the direction opposite the sun.

Why do trees shed their leaves in the fall?

autumn-leaves-ducasse-580

Autumn leaves. Image Credit: Tracy Ducasse.

Something to think about while raking …

Why does the sun look red at sunset?

Image courtesy Tim Haynes

Image courtesy Tim Haynes

Imagine standing on a beach, a mountaintop or any open area, watching a beautiful sunset. As the sun sets, it appears redder and redder as it gets closer to the horizon. Sometimes you can see a gradation of color a across the surface of the sun. Why does this happen?

What is a Blood Moon?

This is what a total eclipse looks like.  This is the total eclipse of October 27, 2004 via Fred Espenak of NASA, otherwise known as Mr. Eclipse.  Visit Fred's page here.

This is what a total eclipse looks like. This is the total eclipse of October 27, 2004 via Fred Espenak of NASA. Visit Fred’s page here. We astronomy writers often describe a totally eclipsed moon as appearing ‘blood red.’ Here’s why the moon turns red during a total eclipse.

The first Blood Moon eclipse in a series of four happened on the night of April 14-15, 2014. The next one will be on the night of October 7-8, 2014.

Why aren’t there eclipses at every full and new moon?

Photo credit: pizzodisevo

A solar eclipse happens at the new moon – when the moon passes between the sun and Earth. A lunar eclipse happens when the Earth, sun and moon align in space, with Earth in the middle. Why aren’t there eclipses at every full and new moon?

Why do tree leaves turn red in fall?

Image Credit: treehouse1977

Image Credit: treehouse1977

In the fall, the leaves of some trees turn yellow, orange or red. The bright colors are wonderful to behold. But do they have some hidden purpose?

What’s the birthstone for October?

Photo credit: Orbital Joe

Tourmaline via Orbital Joe

Meet tourmaline. It’s one of two birthstones for October. The other October birthstone is opal. More info inside this post. And happy birthday October babies!

How to watch a total eclipse of the moon

Total lunar eclipse mosaic by eclipse master Fred Espenak.   Visit his page for the April 14-14 eclipse.

Total lunar eclipse mosaic by eclipse master Fred Espenak. Visit his page for the April 14-14 eclipse.