Ch. 8 Mars Flashcards
Physical characteristics
- Diameter
- Avg dist from Sun
- Mass
- Orbital pd
- Rotational pd
- # of moons
- Magnitude
- Diameter = 1/2 X earth
- Avg dust from Sun = 1 1/2 X earth
- Mass = 1/10 X earth
- Orbital pd = 687 earth days
- Rotational pd = 24.6 earth hours
- # of moons = 2
- Magnitude = +1.8 - +2.9
Axial tilt
25 degrees
Seasons
Similar to earth ‘s seasons
Why is it red?
- From iron oxide in soil
- literally rusty
Dark surface
“Canali” (channels)
What does Canali indicate?
Mars has a similar rotation pd to earth
Surface features (3)
- currently dry
- broad plains, shallow craters, extinct volcanoes, long canyons
- bc mars has weaker gravity, it’s surface features = more extreme than earth’s
Vastitas borealis
Northern lowland
Southern highlands (2)
- heavily cratered
- hilly plains
Mariner valley location (3)
- between hemispheres
- begins with heavily-fractured terrain in west
- ends with ancient-cratered terrain in east
Mariner valley size
1/5 circumference of mars
Mariner valley origin
Believed to be a large crack that formed as planet cooled
Impact craters location
Most located in southern hemisphere
Location of volcanoes
Most in northern hemisphere
Olympus mons (2)
- largest volcano in s.s.
- 3X height of mt. Everest
Other “artificial” features (3)
Photos have shown:
- Pyramids
- Skull
- Happy face
Interior of mars (2)
- evidence of ancient plate tectonics, but no activity today
- more solid than earth’s
Magnetic field (2)
- lacks a global magnetic field
- tectonic activity & magnetic field ended about 4b years ago
Atmosphere Makeup (2)
- 95% CO2
- 5% nitrogen, argon, and oxygen
Atmosphere Characteristics (2)
- composition similar to Venus and ancient earth
- Gravity = too weak to hold water vapor
surface pressure
0.6% of earth’s
Dust (2)
- warm surface creates dust devils
- erodes surface features
no water, but ice
w/e water that was left on mars, as it cooled, froze into ice
watery past (3)
- evidence there was once ocean in n. hemisphere
- most ice in polar caps = water ice
- rest is dry ice
SNC meterorites
pieces of mars that land on earth
Mar’s moons (2) and type of rotation
- Phobos (lg moon)
- Deimos (sm moon)
- synchronous rotations
Phobos (3)
- larger, inner moon
- orbits 3X/martian day
- rises in west, sets in east
Deimos (4)
- smaller, outer moon
- less heavily cratered
- takes about 3 martian days to set
- rises in east
Spacecraft visitors (4) (altogether 8)
- mars 1 & 3
- Mariner 4 & 9
- Viking 1 & 2
- Phobos 1 & 2
mars global surveyor (2)
- launched by U.S.
- photos showed liquid water in 2 craters
mars pathfinder
consisted of lander and lightweight wheeled robotic mars rover (Sojourner)
mars exploration rover A (2)
- 1st of 2 launched = spirit
- stuck in 2009
mars exploration rover B (2)
- 2nd of 2 launched = opportunity
- still active
curiosity
-powered by radioisotope thermoelectric generator