Distances in Space

Astronomical Unit (AU) The average distance between the sun and the earth.

1 AU is equal to 93 million miles or 150 million kilometers An AU is a standard of distance used within the solar system

Example: Jupiter 5.2 AU Light travels 1 AU in eight minutes. Sound travels 1 AU in 14 years

The Planets of Our Solar System The Inner Planets Sizes to Scale Mercury Venus Earth and Moon Mars

The Planets of Our Solar System The Outer Planets Jupiter Saturn Earth Included for Scale. Uranus Pluto Neptune

SIZES AND DISTANCES IN THE SOLAR SYSTEM Diameters of Solar System Members: Sun = 1,392,000 km Mercury = 4,878 km Venus = 12,104 km Earth = 12,756 km Mars = 6,794 km Jupiter = 142,984 km Saturn = 120,536 km Uranus = 51,118 km Neptune = 49,530 km Pluto = 2,304 km Mean Distance from Sun 57,900,000 km = 0.387 AU 108,200,000 km = 0.723 AU 149,600,000 km = 1.000 AU 227,900,000 km = 1.524 AU 778,300,000 km = 5.203 AU 1,427,000,000 km = 10.07 AU 2,871,000,000 km = 19.19 AU 4,497,000,000 km = 30.06 AU 5,914,000,000 km = 39.53 AU Earth’s Moon = 3,476 km Mean Distance from Earth = 384,400 km

Fun Facts About the Planets 18 Mercury’s would fit inside the Earth. Venus is always cloudy. Earth is the only planet we know with life. Mars is red because it is covered with rust. A storm (hurricane) on Jupiter can swallow 2 Earths. Each season on Saturn is more than seven years long. By the time you get to Uranus, you are only halfway to Pluto. Neptune is the windiest planet, with winds blowing over 1,000 miles-per-hour. Pluto is a ball of ice and rock and is a dwarf planet.

Light Year (LY) The distance a ray of light travels in one year The speed of the ray of light would be equal to: 7.2 AU per hour or 300,000 km/sec or 186,000 miles/sec.

Milky Way Galaxy is approx. 100,000 LY across in distance A Light Year is a standard unit of measurement for interstellar distances beyond the solar system. Milky Way Galaxy is approx. 100,000 LY across in distance http://planetquest.jpl.nasa.gov/SIMGuide2Galaxy_508.html

Nearest star to the sun is Proxima or Alpha Centauri C approx 4.22 LY

Proxima (or Alpha Centauri C) is a red dwarf Alpha Centauri A is a yellow star Alpha Centuari B is an orange star

Parsec One parsec is equal to 3.26 light years A parsec is a unit of measurement used for distances between very far structures in the universe. Example: distances between galaxies

Andromeda and Milky Way The Andromeda Galaxy (M31) is slightly less than 800 kpc or 800,000 parsecs away from Earth.