The Solar System

The Sun and the Celestial Bodies

Sun

• Typical medium-sized star• Radiation produced by nuclear fusion

Solar System

• Ten planets and their satellites• Asteroids• Comets• Meteoroids• Interplanetary dust & gas

Major Planets

• Inner planets– Mercury, Venus, Earth and Mars

• Outer Planets – Jupiter, Saturn, Uranus, Neptune, Pluto, and Quaoar

Major Planets

• Inner planets– small, rock and iron

• Outer Planets– mainly hydrogen, helium and ice

(Pluto*)

Movement of Planets

• Elliptical orbits around the sun• Counterclockwise direction around the sun

Discoveries of the Planets

• Mercury – Unknown• Venus – Unknown• Mars – Unknown• Jupiter – Unknown • Saturn – Unknown• Uranus – 1781• Neptune – 1846• Pluto – 1930• Quaoar - 2002

Quaoar, The Newest Planet

• Identified on June 4, 2002 • 800 miles in diameter • Almost perfectly circular 285-year orbit • About 6.3 billion km (4 billion miles) from the sun • Known by astronomers as 2002LM60

Origin

• Debate continues!