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Exploring Mars
Inspiration
Drawings by Dianna Gouskos,
3rd Grade Turner School, April
2000, Mars Millennium Project
Rovers
• Exploration comes from a
combination of sources.
– Earth telescopes
– Orbiters
– Landing craft
• The Rover program has
had seven vehicles.
– Opportunity since 2004
– Curiosity since 2012
http://mars.nasa.gov
Is There Water?
• Schiaparelli (1877) saw “canals” on Mars.
• These were actually shaded areas due to dust storms and
surface features.
• The atmosphere is too thin to sustain liquid water.
Polar Caps
• Like Earth, Mars has polar
caps that change with the
seasons.
• Cold temperatures on
Mars mean that part of the
polar ice is carbon dioxide
as well as water.
Surface Water
• Canyons are evidence of
water that once flowed.
• Boulders on the surface
were moved by ancient
floods.
Underground
• Mars had a thicker atmosphere in the past.
– 3.8 billion years ago
– Lakes and seas
• Some water today is frozen underground, covered by dust.
– Surface outcrops
dust
ice
crust
Is There Life?
• Mars had water and an atmosphere.
• The chemical building blocks are plentiful in space.
• On Earth, life appeared after about 1 billion years.
• First life forms were bacteria.
Mars Rock on Earth
• 16 million years ago, an
asteroid slammed into
Mars.
• Mars rocks were thrown
into space, drifted, and
one landed in Antarctica
13,000 years ago.
• The chemical and gas
composition of the
meteorite matches Mars,
not Earth.
Mars Fossils
• A Martian meteorite from
Antarctica has evidence of
water and carbon.
– 3.6 billion years old
• The meteorite has
microscopic tubes like
bacteria fossils.
• There is no agreement
among experts yet.
Methane Gas
• Methane gas is associated
with organic processes
– No active Martian
volcanoes
• Large areas of methane
detected from the crust.
– Underground bacteria?
– False readings?