change of our veiw on ancient mars
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Water on Mars Okyama University 2007.06.18. Akos Kereszturi , PHD Collegium Budapest Eotvos Lorand University of Sciences Hungarian Astronomical Association e-mail: kru@mcse . hu. Change of our veiw on ancient Mars. Bone dry planet (Mariner-9). Change of our veiw on ancient Mars. - PowerPoint PPT PresentationTRANSCRIPT
Water on Mars
Okyama University2007.06.18.
Akos Kereszturi, PHDCollegium Budapest
Eotvos Lorand University of SciencesHungarian Astronomical Association
e-mail: [email protected]
Change of our veiw on ancient Mars
Bone dry planet (Mariner-9)...
…ancient channels (Viking probes)...
Change of our veiw on ancient Mars
…sometimes lakes (MGS)...
Change of our veiw on ancient Mars
…with a great northern ocean (MGS, MEX).
Change of our veiw on ancient Mars
H2O budget
Signs of liquid water: • channels, valleys• ocean shorelines• clay minerals• sediments deposited in water• theoretical models
Original H2O budget: 20-400 m global coverage
The poposed ancient ocean
Channels by surface runoff or sapping
Global cooling, surface freezing
Realtive small planetary mass:• small radioactive heat source• early stopped dinamo• weak gravity• fast atmospheric loss• decreasing greenhouse effect• decreasing volcanism• only early global tectonism• decreasing global temperature• formation of cryosphere
Water break up, outflow channels
Favourable periods for liquid water
sedimentarydelta
lakesediments
SouthPolarCap
- Argyre- Uzboichannelsystem
Channel network water source
H2O distribution today
Almost all H2O is frozen:• 60-80 % subsurface permafrost• 10-30 % polar cap and polar sediments• 0,1-0,01 % atmosphere
Signs of water today? - Gullies?
Slope straks?
DDS „seepages”?
Possible conditions for water today
• very rarely• who knows…