Next Stop:
Mars!
Earth and
Mars
Mars Stats
Diameter: 6,794 km (53% of Earth)
Mars Day: 24 hours 37 minutes
Mars Year: 687 Earth days
Mass: 11% of Earth
Gravity: 38% of Earth
Mars: 142 million miles from the Sun
Earth: 93 million miles from the Sun
Moons
Mars - two very small moons
Earth - one large moon
Phobos (Fear!)
Deimos (Terror!)
What Is It Like on Mars?
No Birds
No Plants
No Fuzzy Animals
Not much air
Intense radiation
REALLY DRY
Really cold
Atmosphere
Mars has a thin atmosphere with virtually no
oxygen; 95% CO2 / 3% nitrogen
Earth’s atmosphere is much thicker, with oxygen
and water vapor; 78% N / 21% O2
A Dusty Place
• Mars Spirit Rover at Gusev Crater
• Mini-tornados - 20 to 60 mph wind
• 30 to 300 feet wide, up to 6 miles high
Temperature
Mars is very cold -125 to +20 C (-193 to 68 F)
Earth is temperate - 15C (60F) average
Water
• Mars is very dry with no liquid surface water;
atmosphere too thin; temperatures too cold
• Earth has abundant liquid water
Giant
Volcanos
Olympus Mons: 400 miles across … 22 miles high
Giant
Troughs
Valles Marineris: 2500 miles long … 6 miles deep
Giant
Impacts
(and small ones,
too)
A Geologic Time Machine
Mars and Earth formed 4.5 billion
years ago. Early Mars appears to
have been warmer and wetter …
What Evidence Would You
Expect to Find if Water
Flowed Across the Surface?
With the Possibility of Water …
… The Possibility
of Life!
Clear Proof –
“Face on Mars”
Clear Proof –
“Face on Mars”
Viking Landers …
• Look for evidence of respiration,
response to nutrients.
• No evidence for organic molecules at the
parts per billion level.
Life on Mars?
• Claimed evidence
for life in martian
meteorite is not
generally
accepted.
Mars 2030!