The Solar System

The Solar System is a gravitationally bound system of the Sun and the objects that order it

AU or Astronomical Unit: The distance between the Sun and Earth. 1 AU ≈ 149,597,870.7 kilometers or 92,955,807.2 miles

Sun

Mercury : 0.31-0.59 AU from the Sun

Venus : 0.72-0.73 AU from the Sun

Earth : 0.98-1.02 AU from the Sun

Mars : 1.38-1.67 AU from the Sun

Astroid Belt : 2.3-3.3 AU from the Sun

Jupiter : 4.95-5.46 AU from the Sun

Saturn : 9.08-10.12 AU from the Sun

Uranus : 18.3-20.1 AU from the Sun

Neptune : 29.9-30.5 AU from the Sun

Centaur

A centaur is a small Solar System body (SSSB) that orbits the sun between Jupiter and Neptune and crosses the orbits of one or more of Jupiter, Saturn, Uranus, and Neptune.

Centaurs exhibit characteristics of both comets and asteroids. They generally have unstable orbits with lifetimes of a few million years.

The first centaur to be discovered was 944 Hidalgo in 1920.

Milky Way

Our galaxy, the Milky Way, is a barred spiral galaxy with an estimated 100-400 billion stars. It is part of the Local Group of galaxies which forms part of the Virgo Supercluster.

Black Holes

Black holes are regions of spacetime where gravity is so strong that nothing, not even light, can escape. They are thought to result from the warping of spacetime caused by a very heavy object.

Neptune's Moons

Neptune has 14 known moons. The largest, Triton, orbits in a direction opposite to Neptune's other moons, suggesting it might have been captured by Neptune's gravity.