Astronomy is a broad discipline covering all facets of astrophysics. In this section you can learn about the origins of the universe, black holes and other astronomical phenomena.

A massive planet 10 times the size of Earth seems to have been lurking on the edge of our solar system for some time now. How come we never noticed it before?

Over billions of years, the universe has produced a lot of worlds. How does it happen? Astronomers are studying young stars and the exoplanets forming around them.

Pluto may have escaped our notice for a long time in recorded history, but the amazing images from NASA's New Horizons mission have more than made up for that.

The HowStuffWorks Now team visited the James Webb Space Telescope at Goddard to see exactly what this awesome telescope is all about. Come see for yourself.

Sometimes you can't be afraid to throw an elbow, even if you're a planet.

Mars expert Robert Zubrin looks at the bestselling novel "The Martian"—and the new Matt Damon movie—for hazards interplanetary explorers would face.

We'll give you yet another reason why dark matter is cooler than visible matter.

When you think about massive, mysterious cosmic bodies like accretion disks, the water swirling around your bathtub probably isn't the first thing to come to mind. But hey, physics works the same magic on all scales.

These days, we may take the stars for granted, but it's not hard to imagine the wonder early humans must have felt gazing up at those inexplicable points of light. Naturally, superstitions were bound to develop — some more fortuitous than others.

Relying on a collapsed star to power our lives on Earth might seem like a good solution to our energy crisis, but there's just one tiny problem: The process might be lethal.

A single pulsar is fascinating enough, but as a set, these rapidly rotating neutron stars help scientists figure out mysteries of the universe.

It's not uncommon for planets to wander alone through the universe like big, sullen teenagers. But how do they end up flying solo, and could they still harbor life?

Our knowledge of space changes all the time as new discoveries are made. But some ideas about the universe have never really held water – including the one that everything is made of frozen H2O.

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

When a huge star collapses, it releases massive amounts of radiation in concentrated streams. If one of those streams hit Earth, it wouldn't be pretty. But where should we put "gamma-ray bursts" on our list of anxieties?

Precipitation does fall from the clouds of other planets, but it's a little more exotic than the good, old-fashioned rainwater we get here on Earth. Imagine sheets of methane, sulfuric acid and, yes, even diamonds falling from the sky.

Leash your cheetah, buckle your seatbelt and tell Usain Bolt to take a knee. We're about to power through some of the speediest stuff this universe – both in the real world and in fiction – has to offer.

Do the two meet for one final, fantastic explosion? Or maybe the sun just gets a bit of wind? Or maybe nothing of consequence happens at all? Only one way to find out.

They exist in the netherworld between solar systems. Sometimes they arise after being ejected from their orbits, endlessly roaming the Milky Way. Could a nomad planet ever wander a little too close?

Killer asteroids are all fun and games -- until they're headed for Earth. How do we stop cosmic hot potatoes from wiping out our planet?

One tragic, moonless night in April 1912, the Titanic slid into the depths of the North Atlantic Ocean -- for good. A crew of Texas State academics suggested that Earth's favorite satellite may have some explaining to do.

It's not a pleasant thought, is it? But when you mix chaos theory with a few crazy cosmologists, those tidy, predictable orbits start getting lively.

What if your job were to protect life in the galaxy at all costs? That's exactly what the folks manning NASA's Planetary Protection office do, and bunny suits are just the beginning.

A lunar land rush is the most likely thing in the world (or, rather, out of it). As private companies gaze spaceward with dollar signs in their eyes, it's time to start settling some questions about space ownership, use and management.

A dying star can explode with the force of a few octillion nuclear bombs and create any element in the universe. But why do stars go supernova?