The Solar System

SUN 75% hydrogen and 25% helium by mass Sun converts hydrogen to helium using nuclear fusion in its core. Differential rotation –e–e–e–equator the surface rotates once every 25.4 days –n–n–n–near the poles it's as much as 36 days Core conditions –t–t–t–temperature is 15.6 million Kelvin –p–p–p–pressure is 250 billion atmospheres

The solar system consists of:  The Sun  Eight planets  3+ "dwarf planets"  130+ satellites (moons & rings)  Small bodies ( comets and asteroids)  Interplanetary medium (dust, gas, etc…)

Definitions The IAU resolved in 2006 that planets and other bodies in our Solar System, except satellites, be defined into three distinct categories: 1)“Planet” -bodies that: a.Orbit the Sun b.Assume round shapes (hydrostatic equilibrium) c.clear their neighborhood. 2)“Dwarf planet” -bodies that: a.orbit the Sun b.Assume round shapes (hydrostatic equilibrium) c.have not cleared the neighborhood around their orbits. 3)“Small Solar System Bodies” a)All other objects orbiting the Sun

Classifying Planets The eight planets are classified in several ways: by composition: –terrestrial or rocky planets: Mercury, Venus, Earth, and Mars: The terrestrial planets are composed primarily of rock and metal and have relatively high densities, slow rotation, solid surfaces, no rings and few satellites.The terrestrial planets are composed primarily of rock and metal and have relatively high densities, slow rotation, solid surfaces, no rings and few satellites. –jovian or gas planets: Jupiter, Saturn, Uranus, and Neptune: The gas planets are composed primarily of hydrogen and helium and generally have low densities, rapid rotation, deep atmospheres, rings and lots of satellites.The gas planets are composed primarily of hydrogen and helium and generally have low densities, rapid rotation, deep atmospheres, rings and lots of satellites.

Terrestrial planets (Interiors)

Jovian Planets (Interiors)

Classifying Planets (con’t) By SIZE:

Terrestrial planets (Size) Mercury Venus Earth Mars Small planets: Mercury, Venus, Earth, Mars. diameters < km.

Jovian Planets (Size) GIANTS: Jupiter, Saturn, Uranus and Neptune. diameters > km. Sometimes called gas giants.

Classifying Planets (con’t) by position relative to the Sun: inner planets: Mercury, Venus, Earth and Mars.inner planets: Mercury, Venus, Earth and Mars. outer planets: Jupiter, Saturn, Uranus, Neptune.outer planets: Jupiter, Saturn, Uranus, Neptune. The asteroid belt between Mars and Jupiter forms the boundary between the inner solar system and the outer solar system.The asteroid belt between Mars and Jupiter forms the boundary between the inner solar system and the outer solar system.

Terrestrial planets Terrestrial planets (Orbits)

Jovian Planets -Gas Giants (Orbits)

The Planets (Spin)

Terrestrial Bodies – Scaled Size

(Beyond Neptune’s Orbit)

Which one of these is from Star Wars?