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How often do 7 eclipses occur in 365 days?

Annular eclipse image credit: Wikipedia

Annular eclipse image credit: Wikipedia

The last time seven eclipses occurred in a period of one year was from November 13, 2012, to November 3, 2013. It will next happen in the time period from January 31, 2018, to January 21, 2019.

Video: Why does the moon look so big on the horizon?

The August 10 supermoon might look super big seen near a horizon. But all full moons look big near a horizon, due to an illusion called the moon illusion.

What’s the birthstone for August?



Happy birthday to our August friends! This is one of your birthstones, peridot. Your other birthstone is sardonyx.

Read about both your birthstones….

How to see anticrepuscular rays

View larger. | Anticrepuscular rays - seen in the east at sunset - in Nevada.  Shreenivasan Manievannan posted this photo on EarthSky Facebook in July 2014.  Visit Shreeniclix Photography.

Anticrepuscular rays – seen in the east at sunset – in Nevada. Shreenivasan Manievannan posted this photo on EarthSky Facebook in July 2014.

Next time you see crepuscular rays or sunrays extending from the horizon … turn around. You might catch a glimpse of elusive anticrepuscular rays.

Can sharks smile? Do they even feel happy?

The Discovery Channel’s Shark Week is coming up (starts August 10) and sharks are on our mind ….

Attributing emotions to animals is almost irresistible to most people, and some animals do seem to show happiness, anger, fear, and other feelings. Dogs, cats, dolphins, and monkeys can be especially expressive. So … how about sharks?

Will the Andromeda galaxy someday collide with our Milky Way?

Image Credit: NASA, ESA et al.

This image represents Earth’s night sky in 3.75 billion years. The Andromeda galaxy (left) will fill our field of view then, astronomers say, as it heads toward a collision with our Milky way galaxy. Image Credit: NASA, ESA et al.

It’s a question people ask us… Will our home galaxy someday collide with the next-nearest spiral galaxy, in the direction of the constellation Andromeda? And if so, when?

Does Earth have a second moon?

Image of Earth with two moons, generated in Celestia software, by Grebenkov in Wikimedia Commons.

Many planets in our solar system have more than one moon. Mars has two moons, Jupiter has 66, Saturn 62, Uranus 27, Neptune 13. But our planet Earth has just one moon. Doesn’t it?

What exactly is twilight?

Photo credit: joiseyshowaa

Photo credit: joiseyshowaa

You can define twilight simply as the time of day between daylight and darkness, whether that’s after sunset, or before sunrise. Astronomers, surely the experts on nighttime, recognize three kinds of twilight, which are explained in this post.

Does your dog pronk?

Among wild animals, pronking may be a way of avoiding predators. But when you see an animal pronk, you can’t but think it’s leaping for joy. More videos inside.

Scared of thunder and lightning? You have astraphobia

Never let your pets watch scary movies. Never a good idea! Image Credit: John Veldboom via Flickr

Thunder and lightning can be scary to pets, too. Image via John Veldboom via Flickr

Bam! Yikes!

Do you – and your dog – have astraphobia?