The Solar System

The Solar System

The Solar System is defined as the Sun and all the objects that orbit the Sun. We usually think just of the Sun, the Moon, and the nine Planets, but there are many other objects to consider including Asteroids, Comets and the Moons of other Planets. An Astronomical Unit or AU is the average distance between the Sun and the Earth, or about 149,600,000km. The radius of the Solar System is roughly 100AU which is the distance at which the Solar Wind meets the Interstellar Medium. However, some Comets have highly eccentric orbits that range out as far as 50,000AU The sun contains 99.85% of all the mass in the solar system, which is roughly 2X10³⁰ kg. That is about 2 trillion trillion trillion tonnes! The solar system is located on the inner edge of a spiral arm of a very average galaxy - the Milky Way. [TB] {SL}