Yvonne Lin 8C

Solar SystemPlanets

• Revolve: when an object goes around/ orbits another object• Rotate: when an object spins on its axis continuously• orbit: the path the planets/ satellites follows when they revolves• There’re 8 planets in our solar system• Inner planets: Mercury, Venus, Earth, Mars• Outer planets: Jupiter, Saturn, Uranus, Neptune• Inner planets were hit constantly by asteroids and meteorites at the first 600

million years• Three requirements to be a planet

• The object must revolve around the sun• It must have enough mass so that it became round due to its own gravity• It must have already cleared out its orbit so that there aren’t similar objects at

roughly the same distance form sun

• Dwarf planets: Pluto, Ceres, Eris• Met the first 2 requirements, missed the third

Inner planets• Between sun and asteroid

belt• Smaller, made out of solid

rock• Craters on planet and

satellites

General Information

Outer planets• Outside of the asteroid

belt• Large, made out of

gases• Have rings

Inner planetsMercury, Venus, Earth, Mars

Mercury• Mercury’s atmosphere contains helium and

sodium

• Three processes that shaped Mercury’s surface

• Impact cratering: when objects like asteroids hit Mercury’s surface

• Volcanism: volcanic activity

• Tectonic activity: Mercury’s crust moved around to adjust for better cooling and contracting

Venus• Referred as “Evening Star”- brightest planet that can be seen from Earth

• Caused by the thick clouds surrounding Venus- reflects sunlight

• Atmosphere contains Carbon dioxide and sulfuric acid

• Retrograde rotation: The other seven planets rotate counter-clockwise, while Venus rotates clockwise.

• its rotation (243 days) is longer than revolution(225 days)

• Venus has a retrograde- opposite direction from the Earth's rotation Sun rise in the west and sets in the east

• Hottest planet in our Solar System- the atmosphere works as a greenhouse and traps the heat

Earth• atmosphere contains: 21% oxygen, 78% nitrogen,

0.9% argon, 0.1% water vapor, carbon dioxide, neon, methane, krypton, helium, xenon, hydrogen, nitrous oxide, carbon monoxide, nitrogen dioxide, sulfur dioxide, and ozone- Protects us form harmful solar radiation and meteors

• Rotational tilt: 23.5°• Earth’s core is made of liquid iron-nickel. The

rotation of the Earth along with the core causes Earth to have a magnetic field

• Satellite: moon

Mars• Some of the meteorites found on Earth are pieces of Mars.

Scientists study these pieces for evidence of tiny ancient bacteria and other signs that life may have once lived on Mars

• Primary element of atmosphere: carbon dioxide (over 95%)

• Mars looks reddish because it have iron-rich soil.

• Olympus Mons: one of the largest volcanoes in the solar system- over 600 kilometers wide and 26 kilometers high

• Satellites: Phobos and Deimos

Outer planetsJupiter, Saturn, Uranus, Neptune

Jupiter• The quick rotation causes the planet to flatten at the poles

and bulge at the equator.

• Atmosphere: hydrogen, helium, sulfur, and nitrogen

• Giant Red Spot: a storm that is in Jupiter's southern hemisphere

• Satellites: 50 named moons, 13 more have been discovered but not yet given official status or names

• Jupiter’s satellite Io is volcanic active

Saturn• Atmosphere: hydrogen and helium

• the rings developed from particles came from the break-up of some satellites.

• Rings: water ice and dust

• Saturn has the lowest density of any planet in our solar system. Its density is so low that it would float in water.

• Seasons last more than 7 Earth years on Saturn

Uranus

• Tilted 98°- looks like it’s rotating sideways from Earth

• Atmosphere: hydrogen, helium, methane

• 27 satellites

Neptune

• Atmosphere: ammonia, helium, methane

• 13 satellites

• Triton: largest satellite of Neptune- scientists believe that Triton was caught by Neptune's gravitational pull, forcing it to revolve around the planet.

Dwarf planetsPluto, Ceres, Eris

Pluto• Satellites: Charon, Nix, and Hydra

• a spectroscope have detected methane frost on Pluto and water frost on Charon

• Charon is almost half the size of Pluto

Ceres• one revolution around the Sun: ≈4.6 Earth

years

• Other objects similar were also found to be orbiting in the same area, and scientists labeled these objects as asteroids, so Ceres became an asteroid, not a planet.

• a mixture of water ice, carbonates, and clays can be found at its surface

Eris• Eris original name was Xena

• Revolution: 557 Earth years

• Moon: Dysnomia

• Eris was not considered a planet because it did not clear out it’s orbit.