Final: Ch 7, 15, 17, and 18 Flashcards
how long ago did most of the objects in our solar system form?
4.5 BYA
how much of the mass in the solar system is contained in the sun?
99.8%
order of the planets from the sun
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune
mnemonic for the order of the planets
My Very Educated Mother Just Served Us Nachos
what is the most massive planet
Jupiter
what direction do all the planets orbit the Sun
counter-clockwise from above the Sun’s N pole
trans-Neptunian objects
objects farther out in the solar system
dwarf planets
the largest trans-Neptunian objects including PLuto and the largest asteroids
qualities of a planet
(a) is in orbit around the Sun
(b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape
(c) has cleared the neighborhood around its orbit.
qualities of a dwarf planet
(a) is in orbit around the Sun
(b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape
(c) has not cleared the neighborhood around its orbit
(d) is not a satellite.
what are the only planets without a moon
Mercury and Venues
name the planet that the moon orbits:
- the moon
- the Galilean moons: Lo, Europa, Ganymede, and Callisto
- Titan
- Triton
- Earth
- Jupiter
- Saturn
- Neptune
asteroids
rocky bodies that orbit the Sun, mainly in the asteroid belt between the orbits of Mars and Jupiter
the Trojan (and Greek) asteroids
asteroids that share their orbit with Jupiter (because Jupiter’s gravity keeps them there)
comets
small, icy bodies made of frozen gases that spend most of their time far from the Sun
cosmic dust
countless pieces of “dust” (usually broken rocks) littered across the solar system
meteor
when cosmic dust enters the atmosphere, it burns up, causing a brief flash
meteorites
larger pieces of meteors that make it to the surface without burning up completely
what are the planets named after
Roman deities
what are the planet’s moons named after
Greek and Roman mythological figures somehow connected to the planet-deity (except Uranus, whose moons are named after characters in English literature)
what are comets and asteroids named after
comets are usually named after their discoverers, while asteroids are named by their discoverers after whatever they like
the giant planets
- Jupiter, Saturn, Uranus, and Neptune
- Uranus and Neptune are much small than Jupiter and Satun
composition of Jupiter and Saturn
- mostly H and He
- Very small solid core of rock, metal, and ice
- Much of the H and He is compressed until it becomes liquid, so the next layer is “spherical ocean”
- Gaseous atmosphere that we see
terrestrial planets
- Mercury, Venus, Earth, Mars
- All 4 are much smaller than the outer planets
- Composed of rock and metal
- Most of the heavier metals are in the cores
- The layered structure of terrestrial planets indicates that they were molten at some point