Mars:

Earth’s little brother

What are the similarities and differences you notice?

Mars’s axis is tilted at 25 deg. What are seasons on Mars like?

Mars’s axis tilt changes dramatically. What happens when the tilt is less/more?

Artist’s depiction of an ‘icy Mars’

Do the Earth and Mars have similar interiors?

Why?

How do we even know what’s inside a planet?

Atmospheres: Are they similar?Why?

Nitrogen: 78%

Oxygen: 21 %

Argon: 0.9%

Water: > 1%

Carbon Doxide: 0.002%

Carbon Doxide: 95.%

Nitrogen: 3%

Argon: 2%

Oxygen: 0.1%

Water: > 0.03%

Constituents:

Is there water on Mars? Why or why not?

Is there water on Mars? Why or why not?

Mars’s south pole

Is there water on Mars? Why or why not?

Phase Diagram of Water

Mars

Earth

Par

tial P

ress

ure

of W

ater

Temperature

Mars or Earth?

Columbia Hills, Mars

Columbia Hills, Mars

Atacama Desert, Chile

Mars or Earth?

Mars or Earth?

Mars or Earth?

Kilauea Volcanoe, Hawaii Olympus Mons, Mars

Mars or Earth?

Dubai, UAE Endurance Crater, Mars

Mars or Earth?

What is the evidence for past water on Mars?

Mars or Earth?

Djado Plateau, Niger Valles Marineris, Mars

Mars or Earth?

Mars or Earth?

Mars or Earth?

Holden Crater NE, Mars

Lena Delta, Argentina

Mars or Earth?

Yemen

Mars

Mars or Earth?

Mars or Earth?

NigerMars

Mars or Earth?

Seven minutes of terror

Curiosity descenthttp://www.youtube.com/watch?v=gZX5GRPnd4U

Google Mars

Mars: Take-away messages

•Although smaller than Earth, Mars and Earth are similar in many ways.

•Mars and Earth have similar interiors, although Mars has no liquid outer core, and so no magnetic field.

•Mars geology is/was formed by cratering, volcanism, tectonics and erosion by wind AND WATER!

•(Plate tectonics doesn’t seem to have been important)

•Mars’s atmosphere is very different from Earth’s - lower mass, and full of CO2.

•Mars’s small atmosphere and low temperature makes liquid water unstable at its surface (at least right now).

Percival Lowell’s MarsLowell’s Map of Mar published in 1895

Viking’s Mars 1976

Viking’s Mars 1976