ASTR100 Cheatsheet 2 - 1 star 8 planets 5 dwarf planets 139 moons countless small solar system bodies sun=cantaloupe earth=ball point Jupiter =

ASTR100 Cheatsheet 2 - 1 star 8 planets 5 dwarf planets 139...

This preview shows page 1 - 3 out of 7 pages.

1 star, 8 planets, 5 dwarf planets, 139+ moons, countless small solar system bodies; sun=cantaloupe, earth=ball point, Jupiter = fingertip, Pluto=speck of dustThe Voyage Exhibition: A 1-10 billion scale model of the solar system on the National MallPlanets all orbit the sun in same direction, most planets rotate in same direction; Solar System is flat, disk-shapeTerrestrial Planets= closer to sun, closer together, smaller sizes and masses, higher densities, mostly rock and metal, solid surfaces, warmer surfaces, few moons, no ringsJovian Planets= farther from sun, farther apart, larger sizes and masses, lower densities, hydrogen/helium/ices, no solid surfaces, colder temps, many moons, all have ring systemsThe Sun: hydrogen and helium gas, 1.4 million km diameter, has 99.8% of mass in entire solar systemInner Planets: Terrestrials (small size, low mass, high density, mostly rock, few moons, no rings)oMercury: heavily cratered, barren airless world, 88 day orbit; Venus: surface=thick sulfuric acid clouds, 224.7 orbit, size close to Earth; Earth: has liquid water on its surface, 1 year orbit; Moon: orbit period 27.3 days, cratered surface; Mars: Red Planet, water-ice clouds, polar ice, volcanoes, 1.88 year orbitThe Jovians: large size, massive, low density, mostly gas, many moons/ringsoJupiter: king of planets, 11.9 year orbit, 64 moons, rings; Saturn: lord of rings, 29.4 year orbit, 62 moons, rings; Uranus: rolling, 84 year orbit, 27 moons, rings; Neptune: last of giants, 164.8 year orbit, 13 moons, ringsDwarf Planets: Manaka, Hi’aka, Haumea, Makemake, Dysnomia, Eris, Ceres, Charon, PlutoSmall Solar System Objects: asteroids, cometsKuiper Belt: collection of icy bodies orbiting outer fringes of the solar systemPlanet characteristics: in orbit around the sun, has sufficient mass to assume a round shape, has cleared the neighborhood around its orbitDwarf characteristics: in orbit around the sun, sufficient mass to assume round shape, has not cleared neighborhood around its orbit1. Solar system orbits and rotates in orderly pattern (all orbit W to E, counterclockwise, nearly same plane, most also rotate in this direction)2. Two main types of planets (terrestrial, jovian)3. Asteroids and Comets populate solar system: Asteroids (small, rocky, most btwn Mars/Jupiter), Comets (“dirty ice”, most beyond Neptune)Solar Nebular Theory= our solar system formed a giant cloud of interstellar gas and dust (nebula=cloud)When solar nebula contracted, rotation rate increased, flattened to disk, temp increased, protosun formed at center
Background image
oConservation of angular momentum= as rotating objects contract, rate of rotation must increaseOrderly motions of solar system are a direct result of solar system’s birth in a spinning, flattened cloud of gasWhy 2 different types of planets: molecules condense into dust grains, grains collide and stick (accretion), grow into planetesimals, collect into protoplanets; temp controls what planets are made of; gravity drew in particles to create planets
Background image
Image of page 3

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture