A new study suggests that a close encounter with a massive interstellar object, possibly eight times the mass of Jupiter, may have significantly altered the orbits of the four outer planets in our ...

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 ...

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 ...

Scientists have long puzzled over why all of the planets in Earth’s solar system have slightly slanted orbits around the sun. But a new, Yale-led study suggests this phenomenon may not be so unusual ...