SPONGE

What objects make up our solar system ?

Solar SystemSolar System

Solar System – composed of the Sun (a star) and the planets and other bodies that travel around the Sun.

PercentagesPercentages

Sun: 99.85% Planets: 0.135% Comets: 0.01% ? Moons: 0.00005% Minor Planets: 0.0000002% Meteoroids: 0.0000001% Interplanetary Medium: 0.0000001%

Solar System StructureSolar System Structure

The planets revolve around the Sun in orbits that lie close to a common plane. (Mercury 7o ; Pluto 17.2o)

All planets orbit the sun in a counter-clockwise fashion as seen from above the north pole of the sun. Orbits are contained within a very narrow disk or plane.

Most orbits are elliptical with the exception of Mercury and Pluto.

Small Rocky WorldsSmall Rocky Worlds Terrestrial Planets – the small, dense,

rocky planets of the inner solar system. Mercury Venus Earth Mars

Terrestrial PlanetsTerrestrial Planets

Big Gaseous WorldsBig Gaseous Worlds

Gas Giants – the large, gaseous planets of the outer solar system.

Jupiter Saturn Uranus Neptune

– All gas giants have rings!

Gas GiantsGas Giants

PlutoPluto Pluto – doesn’t fit either category. Pluto is

a small icy world clearly different from either the Terrestrial and Gas Giant worlds.

Acronym for Order of Acronym for Order of PlanetsPlanets

MM VV EE MM JJ SS UU NN

Age of the Solar System

Oldest Rocks dated on Earth ~ 3.9 billion years, however the Earth’s own volcanism and plate-tectonics erase most of the evidence!!

Lunar Rocks are dated to 4.48 billion years. Meteorites ~ 4.6 billion years Sun estimate based on all the circumstantial

evidence ~ 5 billion years.

Formation of a Solar Formation of a Solar SystemSystem

Solar Nebula – the nebula that formed into the solar system.

OUT: Summarize the difference between terrestrial planets and gas giants.