In the Solar System Channel, you can explore the planets and celestial objects around our own sun. Learn about topics such as Mars, Jupiter and the Moon.
Neptune is the eighth planet from the sun, the fourth largest, and a gas planet. It is named after the Roman god of the sea. Neptune is four times the size of Earth, and its day lasts a little more than16 hours. Its year is about 165 Earth years. Neptune's orbit is a perfect circle. The last stop on spacecraft Voyager's epic trip through the solar system was the gas giant Neptune. See more »
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.
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Where I live it is pretty common to see "shooting stars" -- streaks of light in the sky at night. How big is a shooting star? Do they land on earth or do they burn up? Do they land on the ground as meteorites?
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A ball of fire blazed through southern Peru and left a huge crater -- and then villagers started getting sick. Early reports said the groundwater boiled and the air filled with sulfur. What happened?
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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.
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Since the 1960s, we've been captivated by our planetary neighbor. How different is the planet next door, and what have we learned about it so far, compliments of the Phoenix Mars Lander and other spacecraft?
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A total solar eclipse is a rare event that can be an amazing thing to witness. Learn about solar eclipses and how to observe one safely.
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Sunspots are peculiar dark areas that show up regularly on the surface of the sun -- and often for no reason. What causes them? What effect could these funny little spots have on the Earth?
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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?
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Having cell phone trouble? Believe it or not, the culprit could be eruptions of charged particles on the Sun. This week saw one of the largest solar flares in 20 years. Learn all about that huge ball of light in the sky.
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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?
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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?
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Since the 19th century, humans have wondered about the prospects of life on Mars. While we haven't sent anyone to the Martian surface, we have sent spacecrafts, which have gathered a good amount of information on what it's like on Mars. How is it different from Earth? How is it similar? And could life really have existed there long ago, or exist in the future?
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Wolves supposedly howl at it, a fairy tale claims a cow once jumped over it, and legends say if you look hard enough, there's a man in it. Yes, the moon has a prominent place in popular culture, but there's a lot you might not know about Earth's little orbiting friend. Why doesn't it have soil? Why is its gravity so important? And are we really thinking of going back soon?
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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?
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Although other planets have rings, none are as spectacular as Saturn's. What makes the planet's stratified rings, and how did they get there in the first place?
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You've probably heard that staring at the sun is bad for your eyes. Even a few seconds can damage your eyes. But what if you looked at a solar eclipse?
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We know it's not made of green cheese, but what are the origins of the moon? Learn astronomers' theories about where the moon came from.
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On August 24, 2006, the International Astronomical Union (IAU), an organization of professional astronomers, passed two resolutions that collectively revoked Pluto's planetary status.
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Hundred of meteors fly across the sky every night, but only a few make it to Earth. Meteors are best known for the brilliant streaks of light they make as they burn up in the atmosphere. Learn about 10 memorable meteor crashes that left an impression.
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Jupiter is the largest planet and is fifth from the sun. It is the third-brightest spot in our skies--after the sun and Venus. Jupiter is made up almost entirely of gas, which means it doesn't have a solid surface like Earth does.
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