The Solar
System
The Structure of the Solar System
The Sun 4 Inner planets 4 Jovian planets 8 Dwarf planets
30 objects highly likely to be dwarf planets 60 objects which are likely to be dwarf planets 103 objects which are probably dwarf planets 394 objects which are possibly dwarf planets
The Sun
One of 100 billion stars in our galaxy The largest object in our solar system.
Contains >99.8% of the mass in our solar system
70% H, 28% He Energy produced by nuclear fusion
Mercury
Closest planet to the sun (0.4 AU), an inner planet
Terrestrial Named for Mercury, the
Roman messenger of the Gods
Similar in size to our moon (0.4x the size of Earth)
Iron-nickel core with silicate mantle
Mercury
Takes 59 days to spin on its axis
88 days to orbit the sun Gravity is 0.38x that of
Earth’s HOT days and COLD
nights (-183C – 427C) Atmosphere of sodium
and helium No moons known
Venus
Inner planet, 0.7 AU from sun Named for the Goddess of Love We can see it in the sky Similar to Earth’s mass and diameter Thick atmosphere of CO2, nitrogen
and sulphuric acid Very hot 480⁰C (runaway greenhouse
effect) Spins opposite of other planets,
takes 243 days to spin
Venus
One year = 224 Earth days
Gravity is 0.9x that of Earth’s
No known moons
Earth
Largest of the inner planets
Liquid water helps support life
Crust, mantle, liquid core, solid core Mantle consists of Mg, Fe,
SiO4
Core consists of Fe and Ni Not too hot, not too cold!
Earth
An inner planet, 1.0 AU from the sun Takes 23h, 56 min to spin on its axis Takes 365.25 days to orbit the sun Average temperature is 14C Atmosphere is 77% nitrogen, 21%
oxygen One moon – “the moon”
Mars
Named after the Roman god of war
Red in colour (iron oxide, Fe2O3) Atmosphere of Carbon Dioxide
(95.3%) and Argon 0.5 x Earth’s diameter 1.5 AU from the sun (inner
planet) A day on Mars is just a few
minutes longer than on Earth (24 hours, 37 min)
Mars
Olympus Mons – the largest volcano in the solar system (3x height of Mt. Everest)
Water on Mars (but not as much as Earth) Locked in permafrost in ice caps
2 moons: phobos and deimos
Average Temp: -63C Takes 687 days to orbit
the sun Gravity 0.38 of Earth’s
Asteroid Belt
Between Mars and Jupiter
Total mass would equal 10% of Earth’s moon
Ceres is the only dwarf planet in the inner solar system
Jupiter
Named after Roman king of the gods
5.2 AU from the Sun (outer planet)
Largest planet (11.2x the size of Earth)
Giant gas ball (atmosphere of H and He)
Solid core of Fe, rock, and H2O
Jupiter
66 moons discovered Huge storms – largest
storm is the Great Red Spot (so big, all of Earth could fit in it!)
Very faint rings Average temp: -130C Gravity: 2.64 x Earth’s 1 day = 9h, 55 min 1 year = 11.86 years
Saturn
Named after Roman god of agriculture
Large and beautiful ring system Ice with some rocky
material Atmosphere of H and He Lightest of all planets 62 moons discovered
Titan is a bit larger than Mercury
Saturn
9.6 AU from sun 9.5 x the size of Earth 1 day = 10 hours, 39
min 1 year = 29 years Gravity is 1.16x
Earth’s Average Temp: -130C
Uranus
Named after Greek god of the sky Coldest planet (-200C!) Blue-green colour ( Hydrogen, Helium and
Methane atmosphere) Tilted axis; spins on its side
One hemisphere almost all day, other almost all night
Uranus
27 known moons Outer planet, 19.2 AU from
sun 4x the size of Earth 1 day = 17h, 14min 1 year = 84 years Gravity = 1.11x Earth’s
Neptune
Named after Roman god of seas Smallest of gas planets (3.9x
Earth) Strong winds – up to 2000km/h Also has methane in atmosphere
causes green/blue colour Atmosphere is H, He, and
methane (CH4) Large storms – also has a ‘dark spot’ 13 moons (including Tritan)
Neptune
30.0 AU away from the sun (farthest ‘planet’) (outer planet)
1 day = 16h, 7 min 1 year = 164.8 years Gravity is 1.21x that on
Earth Cold! About -200C
Dwarf Planets (Including Pluto) A dwarf planet is a celestial
body that: Orbits the sun. Has enough mass to assume a
nearly round shape. Has not cleared the neighborhood
around its orbit. Is not a moon.
The first five recognized dwarf planets are Ceres, Pluto, Eris, Makemake and Haumea.
Dwarf Planets (Including Pluto) 8 Dwarf planets
30 objects highly likely to be dwarf planets 60 objects which are likely to be dwarf planets 103 objects which are probably dwarf planets 394 objects which are possibly dwarf planets