A vast ring of rocky leftovers between Mars and Jupiter, the asteroid belt preserves clues to how the planets — and Earth ...

Although the term itself immediately conjures the sort of alchemy at the heart of the best sci-fi fantasy, celestial mechanics —- the numerical nuts and bolts of how planetary bodies move, orbit and ...

The giant planets weren't always where we find them today. Jupiter, Saturn, Uranus and Neptune formed in a more compact ...

An artist's depiction of a hot Jupiter planet orbiting its star. Skewed planetary pathways around a star aren't so strange after all. But fresh research led by Yale University shows that even ...

"This is really like looking at ourselves in a funhouse mirror." When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Skewed planetary pathways around ...

For the inner four planets in this solar system, each planet orbits the sun three times for every two orbits of the planet immediately to its outside. For the fourth, fifth and sixth planets, they ...

EVANSTON, Ill. — Except for the fact that we call it home, for centuries astronomers didn’t have any particular reason to believe that our solar system was anything special in the universe. But, ...

A new study of the orbit of comets suggests that the plane of the ecliptic, where the Earth's orbit rests, may not be the only major alignment in the solar system. By tracking the point where ...

An international team of astronomers has discovered eight new extrasolar planets, bringing to nearly 80 the number of planets found orbiting nearby stars. The latest discoveries, supported by the ...

When it comes to planets in our Solar System's habitable zone, one world is too close to the Sun, another is too far and ...

Jupiter is already the biggest planet by far in our solar system, but new research suggests it was somehow once even larger than it is now. Twice as large, in fact. To put that into context, those ...

This story appears in the July 2013 issue of National Geographic magazine. The dust speck had been plucked from the tail of a comet more than 200 million miles away. Now, under an electron microscope ...