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 ...

Mercury takes only 88 Earth days to orbit the sun.

Our Solar System is a carefully balanced celestial dance held together by a virtually perfect balance of gravity and inertia.

Then use the table above and the equation: Weight = mass x gravity to investigate how your mass and weight would vary from planet to planet. Here is a typical set of results for a student whose ...

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 ...

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 ...