Mars ♂

• Valles Marineris
  • Mariner Valley
  • Complex system of canyons
  • As long as the United States is wide
• Eccentricity of Mars' orbit is 0.1
  • Nearly indistinguishable from a circle
  • See planetary motion
• Has evidence of habitable conditions in the past
• 1.52 AU from the Sun
• Diameter of 6790 km
  • Just over half of Earth's diameter
  • Total surface area is close to the land area of Earth
• No magnetic field in present day
• Red colouring comes from iron oxides in the soil
• Polar caps
  • Visible by the unaided eye
• Mars has qualities like Earth
  • Sidereal day is 24 hours 37 minutes 23 seconds
  • Tilted 25˚
  • Experiences seasons lasting ~6 Earth months
• Possibility for past life
  • Thin atmosphere exists
    • Would've been thicker in the past
  • Existence of liquid water
• Experienced extensive volcanic activity at the same time the Moon did

Atmosphere

• Less than 1% of the atmospheric pressure of Earth
• Components
  • 95% carbon dioxide
  • 3% nitrogen
  • 2% argon
• Gas proportions are similar to Venus but there is a lot less of each gas
• Thin atmosphere
• Low greenhouse effect
  • Runaway refrigerator effect

Surface

Polar Caps

• Seasonal caps are composed of frozen carbon dioxide (dry ice)
• Permanent or residual caps are composed of frozen carbon dioxide and water ice

Water Features

• Runoff channels
  • Look like what geologists would expect from surface runoff of ancient rain storms
  • Hint at a very different climate than we see today
• Outflow channels
  • Much larger than runoff channels
  • Possibly carved by huge volumes of running water
• Gullies
  • Erosional features that look to be caused by running water

Moons

• Phobos and Deimos are probably captured asteroids
• Members:
  • Phobos
  • Deimos

Astronomy Space Planet