The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

Ever since Isaac Newton famously talked about gravity, its dominance as a force in our solar system has been well known. It's responsible for the orbits of the planets and their satellites, but there ...

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit ...

All solar system planets have fairly circular orbits with relatively minuscule differences in their distance from the sun at aphelion and perihelion. Venus and Neptune follow the most circular orbits.

This may explain the strange properties of the orbits of our solar ... the solar system formed," the researchers wrote in the paper. "Given that the estimated population of sun-like stars in ...

It's possible a heavy object fell into the mix early in the Solar System's formation, leaving an everlasting impression ... Solar System tumble towards the Sun's mass from time to time, typically ...

As the sun geared ... us predict when a solar flare may be about to head our way, according to a new paper in the Astrophysical Journal Letters. Having an early-warning system for solar flares ...