Planets of the Solar System

By: Kevin YuScience 8C

General Information

• All the planets in The Milky Way revolve around the sun. ( Circling around)

• Most/all the planets and moon rotate on themselves. ( Spin on own axis)

• All these planets have their own gravity, the bigger the mass is the more gravity a planet/moon has.

• A mass will become a planet if it has a round enough shape, revolves around the sun, and has its own gravity.

Inner/Outer Planets

• There are 8 planets in our solar system, Mercury, Venus, Earth, and Mars are inner planets, and Jupiter, Saturn, Uranus, and Neptune are the outer planets, as well as 3 dwarf planets.

• These inner and outer planets are seperated by the asteroid belt.

• Inner planets are often filled with craters from the many asteroids crashing it.

• While inner planets are made of solid rock, outer planets are mostly made out of gases.

Mercury

• Mercury’s atmosphere is not substantial because it’s too close to the sun, and it contains helium and sodium.

• Mercury is the closest to the sun. It can reach up to 427°c when facing the sun, and below -183°c when facing away from the sun.

• Mercury has no atmosphere and is shaped by volcanos, tectonic plates, and asteroid and meteor impacts.

Venus

• Venus is also known as “The Evening Star” from Earth because of the light its cloud reflects.

• A year in venus is even longer than a day at venus because of its slow rotation. Venus has a retrogade rotation, meaning it rotates the opposite direction from Earth, resulting the sun to rise from west to east there.

• You would think Mercury is the hottest planet since it’s closest to the sun, but Venus is. Its greenhouse effect traps the heat in the planet.

Earth

• Our atmosphere contains 21% oxygen, 78% nitrogen, 0.9% argon, and 0.1% other elements. The atmosphere protects us from solar radiation and most meteors.

• Earth lies on a 23.5 degree angle tilt, giving us seasonal variations. Earth also has a magnetic field produced from the molten metal inside Earth, and Earth’s fast rotation.

• The Moon is the natural satellite of Earth and is often seen at night.

Mars

• Mars looks generally red because of the iron rich soil laying there.

• Mars is also believed to have life because of tiny bacteria found from there.

• 95% of Mars’s atmosphere is carbon dioxide.• Mars also has the largest volcano in our solar

system which is “Olympus Mons”. It is 26KM tall.• Mars also has 2 natural satallites which are

Phobos and Deimos.

Jupiter

• Its flat poles and bulgy equator makes it rotate very fast.

• Jupiter’s atmosphere contains hydrogen, helium, sulfur, and nitrogen.

• There is a giant red spot on Jupiter believed by scientists to be a huge hurricane.

• Jupiter has over 50 natural satellites and one of them, Io, has volcanic activity on it.

Saturn

• Saturn’s atmosphere consists of hydrogen and helium.

• Saturn has a large rings of ice and dust believed to be formed by the break up of nearby satellites.

• Saturn has long seasons because it takes about 29.5 years to complete on revolution.

• Saturn has such a low density, it can even float on water.

Uranus

• Uranus, unlike other planet has a tilt of 98° and practically rotates horizontally.

• Uranus’s atmosohere includes hydrogen, helium and methane.

• Uranus has up to 27 known natural satellites.

Neptune

• Neptune has an atmosphere of ammonia, helium, and methane.

• Neptune has 13 known natural satellites.

• Neptune’s largest natural satellite is Triton, and is believed that it is not originally Neptune’s satellite until Neptune’s gravitational pull grabbed Triton in its orbit.

Dwarf Planets

• A dwarf planet is a planet that fails the third requirement of being a planet: Having its own gravity.

• There are lots of dwarf planets, three of the more known ones are: Pluto, Ceres, and Eris.

• Pluto used to be an outer planet.

Pluto

• Pluto has 3 natural satellites, Charon, Nix, and Hydra.

• Scientists using a spectroscope have found that Pluto’s atmosphere contains methane and nitrogen.

• It is also been found that one of Pluto’s satellites, Charon, shares the same atmosphere with Pluto.

Ceres

• Ceres takes 4.6 years to finish one revolution around the sun.

• Ceres was once thoght as an asteroid, because it is located in the asteroid belt.

• Ceres’s surface is covered with things lyk ice, water, carbonates, and clay.

Eris

• Eris was originally named Xena and has a natural satellite named Dysnomia.

• It takes up to 577 years to complete one revolution!

• Eris was originally not considered a planet until the category of “Dwarf Planets” came out.