Fig. 10.2

Fig. 10.1

Mars is now a barren, geologically dead, dry world

Solid carbon dioxide (dry ice) polar caps

Polar caps shrink and grow with seasons

Mars has secondary atmosphere 95.3 % CO₂

Reverse runaway greenhouse effect

CO₂ absorbed by rocks

Greenhouse effect diminished as greenhouse gases left atmosphere

Thinning atmosphere not able to hold in IR radiation

Rapid cooling

Fig. 10.2

Mars, Venus, and Earth

Fig. 10.19, 9.17, and 7.2

Geographic and Topographical evidence for flowing and standing water on Mars in ancient times

Possible permafrost-a layer of water ice under the surface. Evidence of permafrost in fluidized ejecta crater

Fig. 10.12b- outflow channel evidence of catastrophic flood 3 billion years ago

Fig. 10.13b -Evidence for standing water or wind erosion in Holden crater

ALH84001 Meteorite (Discover 10-2)

Orange brown globules in inset form with water- evidence for liquid water

Rod shaped structures in right hand picture could be organic (life) or inorganic byproducts

Phobos ("fear") and Deimos ("panic")

26 km and 16 km long, respectively, potato-shaped

Tidally locked, synchronous rotation

Captured asteroids?