Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of collapsing gas created our Sun, the first thing to form in ...

A planet 100 light-years away that resembles a young Jupiter has been discovered by an international team of astronomers that includes six UCLA scientists. The discovery is reported Aug. 13 in the ...

Jupiter, the largest planet in the solar system, was 2 to 2.5 times bigger in its earlier life, according to new research. Jupiter, the largest planet orbiting the sun, used to be much bigger and ...

The solar system is 4.54 billion years old, based on rock dating. Gas giants (Jupiter and Saturn) likely formed first. Ice giants (Uranus and Neptune) probably formed next. Rocky planets formed last, ...

Discover why the solar system's planets are arranged as they are, shaped by formation conditions and planetary migration.

Jupiter currently shines as a brilliant silvery "star" in the constellation Gemini the Twins, low in the east-northeast sky ...

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit before shoving four of the solar system's planets onto a different course. When ...

TEMPE, Ariz. a Quick: What’s the order of the planets in the solar system? Need a little help? Maybe the following mnemonic rings a bell: “My Very Educated Mother Just Served Up Nine Pizzas.” It’s ...

Six of our cosmic neighbors are expected to line up across the night sky tonight, in what has been dubbed a "planetary parade". Throughout much of January and February, Venus, Mars, Jupiter, Saturn, ...