Chapter 22: Touring Our Solar System Flashcards
What is included in the Solar System?
- Sun
- Eight planets & their satellites (moons)
- Asteroids
- Comets
- Meteoroids
Two groups of the planet that occur in the solar system are?
- Terrestrial (Earth-like) planets
2. Jovian (Jupiter-like) planets (aka gas planets )
Terrestrial planets are what?
“Earth-like”
- Includes Mercury, Venus, Earth, and Mars
- small, dense rocky
- low escape velocities
Jovian planets are what?
“Gas Giants”
- Includes Jupiter, Saturn, Uranus, & Neptune.
- Large, low density, gaseous
- massive in size
- Thick atmosphere
Name the first Dwarf Planet in the solar system and provide its characteristics.
Pluto
Discovered in 1930.
- Not visible w/ naked eye
- Has four small moons
- Has massive temp. swings
What classifies a planet a planet?
- it is in orbit around the Sun
- It has to round itself out to assume
hydrostatic equilibrium - It has “cleared the neighborhood” around its orbit by having enough field of gravity to do so.
New Class of Planets
- They do orbit the Sun
- Not the only object to occupy their area
- Located in the Kuiper Belt
-Over 1,000 KBO’saare known today.
What is the Nebular Hypothesis?
- Planets formed about 5 bill yrs ago
- Solar System condensed from a gaseous nebula
When planets are formed, what materials were needed?
- Dense metallic elements. (sank to center forming cores)
- Lighter elements oxygen, hydrogen migrated to surfaces.
These processes are called Chemical Differentiation.
The General characteristics of the moon are?
- Unusually large
- Gravitational pull to Earth
- No atmosphere
- Tectonic plates are no longer active.
- Surface is bombarded by micrometeorites.
What does the Lunar History Hypothesis suggest?
That giant asteroids collided w/ Earth to produce the Moon.
- Older ares have high density
- Younger ares are still smooth
The moon evolved in what 3 phases?
1) Original Crust
- moon formed, outer shell melted, cooled, solidified, & became highlands, 4.5 mill yrs old.
2) Formation Maria Basins
- caused by asteroids & lava flooding moon surface. (younger than highlands .32 -3.8 mill yrs old)
3) Formation of Rayed Craters
- material ejected from craters is still visible
A Brief Tour:
Mercury
- innermost planet
- smallest planet
- no atmosphere
- smooth terrains
- 3 days = 2 years of Earth
A Brief Tour:
Venus
- Similar to Earth in size, density, & location
- 1 day = 244 Earth days
- Shrouded in thick clouds
- 97% Carbon Dioxide
A Brief Tour:
Venus
- 80% of surface covered by volcanic lava flow
- tectonic formation was once active during the recent geologic past
