Construction and Destruction of Mountains on Mars
When: May 26, 2015 3PM PDT
It is not known whether Earth’s long-term climate stability is rare or common. Kepler data suggest many Earth-radius habitable-zone planets lie within reach of JWST. The fraction of these that are habitable depends on the unknown processes that regulate long-term environmental stability. Mars’ sedimentary record is the only known archive of a major planetary habitability transition. No rivers flow on today’s Mars, but rovers and orbiters have found >3 Ga-old sedimentary rocks, dry rivers and paleolakes, and aqueous minerals. The nature of the early wet era, the processes that allowed surface liquid water, and the cause of climate deterioration, are all unknown.
The “Curiosity” rover is currently exploring a moat encircling a 5km-high sedimentary rock mound in Gale Crater. This moat-and-mound pattern is common in Mars craters and canyons, but its origin is unknown. Edwin Kite will set out the evidence that moats and mounds grew together, shaped by slope winds down the crater and mound flanks, and discuss the implications for liquid water sources on early Mars and for Mars habitability. If time allows, he will discuss ongoing work on connections between time gaps in the Mars sedimentary record (including at Gale Crater) and climate modelling of late bursts of habitability on Mars.