The Solar System

Surely you've watched tons of sunsets in your lifetime. But have you ever seen the sunset and the moonrise simultaneously? Is that even possible?

By Sharise Cunningham

As the search for Planet Nine wears on, and astronomers have yet to get so much as a glimpse of it, researchers are pondering what else the object might be.

By Ian O'Neill, Ph.D.

The Geminid meteor shower is one of the year's stronger displays in terms of number and size of meteors. When's the best time to see it?

By Christopher Hassiotis

The moon has seen a lot in its 4.5 million years of life, and this detailed geologic map serves as testament.

By Jesslyn Shields & Yara Simón

In 1953, CalTech geochemist Clair Patterson came up with an estimate for Earth's age that still holds today.

By Patrick J. Kiger

Check out this video of what astronauts in space see as the shadow of the moon crosses our planet.

By Christopher Hassiotis

And don't worry. Even if NASA misses, we'll be fine.

By Ian O'Neill, Ph.D.

Every autumn, Earth passes through a stream of debris left by Halley's comet, resulting in some beautiful nighttime meteor showers called the Orionids. Here's what to watch for.

By Patrick J. Kiger

Everyone's heard of the blue moon and the harvest moon, but every other full moon of the year has a name, too. What are their names, and when do these moons occur?

By Nathan Chandler

But what?

By Ian O'Neill, Ph.D.

Researchers at the Zwicky Transient Facility have found an asteroid in Earth's orbit. And this one has the shortest year yet.

By Ian O'Neill, Ph.D.

Did you know that a moon can leave its orbit around a large planet and go out on its own?

By Patrick J. Kiger

Until recently, most people assumed that if Mars had liquid water, it no longer did and hadn't for quite some time. But scientists have recently noticed some anomalies in photos of Mars that may suggest there is water. Could there be life, too?

By Sarah Dowdey & Robert Lamb

The changing phases of the moon have given us an enduring curiosity about the dark side of the moon. But is there really a dark side of the moon? What would we see there?

By Jonathan Strickland

The moon is often the largest object in the sky outside of the sun. What is the moon made of, how did it form -- and why do people blame it for their strange behavior?

By Craig Freudenrich, Ph.D.

Asteroid belts aren't quite the dense fields of gigantic spinning rocks that you may have seen in a "Star Wars" film, but they're still fascinating. In fact, the main asteroid belt may tell us how our entire solar system came into existence.

By John Fuller

You've probably heard that staring at the sun is bad — even a few seconds can damage your eyes. But what if you looked at a solar eclipse?

By Katherine Neer & Yves Jeffcoat

After Viking 1 captured images of what looked like a face on Mars, the public began to speculate. Had Martians carved a colossus, or was there another answer?

By Stephanie Watson

The only thing that's lurking in the shadows during a lunar eclipse is the moon. When Earth's shadow blocks sunlight from directly illuminating a full moon, you're witnessing a lunar eclipse.

By Jessika Toothman

A billion years ago, the moon stopped being geologically active. But that's not to say that the moon is doing nothing for Earth. Let's find out why we owe our moon some thank yous.

By Kate Kershner

The annual Leonid meteor shower is back, and peaks in the late-night hours of November 17. It's made up of tiny bits of debris from the comet Tempel-Tuttle. Here's how to see it.

By Patrick J. Kiger

And if we're going to get technical about it, neither do those of us here on Earth.

By Christopher Hassiotis

Energized subatomic particles bombarding Earth from outer space can cause the electronics inside laptops, cell phones and other devices to crash.

By Patrick J. Kiger

How galaxies get their shapes and evolve is widely debated.

By Mark Mancini & Yara Simón

It's the first interstellar rock we've ever found!

By Ian O'Neill, Ph.D.