In the remote outer reaches of planetary systems, far beyond the orbit of known planets, enormous and mysterious worlds silently loop around their stars. Some drift as far as 10,000 times the distance ...

The planets in solar do not have circular orbit around the Sun, including Earth which goes around in an elliptical orbit. A new research is now looking at what really caused this change in the ...

An interstellar visitor. To tackle this puzzle, Malhotra and colleagues considered a less-examined scenario: that a visiting star-size object tweaked these planets' paths around 4 billion years ago.

The planets in order from the Sun are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. If you include the ...

All seven of the other planets in our solar system are about to become visible at once in a great planetary alignment – here’s how to spot the celestial show. Close. Advertisement.

A cloud of collapsing gas created our Sun, the first thing to form in our solar system. This happened about 4½ billion years ago.. Then the planets began to emerge, as the billions of particles ...

All eight of the solar system’s “major” planets appear in this illustration, but the actual number of planetary bodies orbiting our star is far greater. Digital Vision/Getty Images.

Our Solar System is full of mysteries, but if the inner planets are a puzzle, the boundary between the Solar System and interstellar space is a secondhand puzzle with half the pieces missing.

The Sun and planets of our solar system all formed from the same cloud of gas and dust, but the planets’ compositions vary with mass and distance from our star.