Mitchell Drew and Mariel Henkoff Mission to Titan Mitchell Drew and Mariel Henkoff http://saturn.jpl.nasa.gov/photos/imagedetails/index.cfm?imageId=3701

Saturn Orbital Radius: (Average) Radius: Mass: Core of rock and ice 1.43 * 109 km (Average) Radius: 58,232 km Mass: 5.68 * 1026 kg Core of rock and ice Metallic, liquid, and gaseous hydrogen layers Gaseous layer also contains helium Magnetosphere shields planet, rings, and moons 62 Moons http://saturn.jpl.nasa.gov/photos/imagedetails/index.cfm?imageId=3379

Meet Titan Largest of Saturn’s Moons by far Radius: 2600 km Mass: 1.34 * 1023 kg Orbit: 1 * 106 km 16 day orbit Tidally locked http://photojournal.jpl.nasa.gov/catalog/PIA10487

So what’s so special about Titan? Titan’s atmosphere kept it a mystery for centuries Christiaan Huygens: 1655 Voyager 1 Hubble Cassini Mission Only known moon with dense atmosphere Only known body besides Earth with stable liquids on surface http://apod.nasa.gov/apod/ap041028.html

Titan Earth Atmosphere 1.5 bar N2, CH4, H2 Stratified 1 bar N2, O2, H2O, CO2 Surface ~ -179° C Mountains, river channels Lakes: liquid methane Frozen H2O crust Mounds of hydrocarbon sand dunes ~ 14° C Mountains, rivers, lakes Surface oceans: liquid water Hard silicate crust Interior Suspected ocean 100 km below surface: liquid H2O + ammonia Cryovolcanism and out gassing (methane) Crust Movement? Solid inner core, liquid outer core, solid, viscous mantle, solid crust Volcanism and out gassing of CO2 Plate Tectonics Hydrological Cycle Clouds Methane rain Huge impact on landscape H2O Rain Frequent precipitation Methane vs. Water Surface temperature close to triple point of methane Surface temperature close to triple point of water Water is highly soluble

http://www.astrobio.net/pressrelease/3720/ice-volcanoes-on-titan http://www.chicagospace.org/cassini_saturn.html http://www.space.com/11550-saturn-moon-titan-underground-ocean.html http://apod.nasa.gov/apod/ap070207.html

Cassini Mission: New Questions and Objectives Primary mission launched in 1997, arrived in 2004, extended until 2017 Piqued Interests in Titan Seasonal changes Varying surface composition Interior: liquid mantle, crust movement, magnetic field Atmospheric structure, weather activity Hydrogen question: incompatible hydrogen ratios at surface and in atmosphere Sunlight splits Methane and Nitrogen in upper atmosphere and their atoms recombine to form organic compounds – Net yield of Hydrogen http://vims.artov.rm.cnr.it/doc/img.html http://photojournal.jpl.nasa.gov/catalog/PIA12810

Significance of Hydrogen Depletion Observed processes are consistent with the idea of life Unexplainable discrepancies between Hydrogen in upper atmosphere and in lower atmosphere/surface Hydrogen can easily move through and escape from the atmosphere Hydrogen has a long lifetime Also a lack of predicted acetylene

Methane Gaseous Methane – atmosphere Liquid Methane Surface lakes Hydrological Cycle Question of presence of methane Broken in upper atmosphere by sunlight Concentration is maintained with no explainable source Cryovolcanism? http://www.scientificamerican.com/article.cfm?id=lets-go-sailing-on-lakes-of-titan-2009-11

Life on Titan? Proposed alternative form of life Methane based Solubility of methane is less than water Accommodations by life could include large surface to volume ratios and active transport Could explain hydrogen depletion and methane production Consume hydrogen like oxygen Consume acetylene like glucose Produce methane like carbon dioxide http://autocww.colorado.edu/~toldy2/E64ContentFiles/VirusesMoneransAndProtists/Amoeba.html http://www.badmovies.org/movies/brainarous/

Cassini-Huygens Huygens Probe Transmitted information for 2.5 hours while descending through atmosphere ~70 minutes on surface http://www.esa.int/esaMI/Cassini-Huygens/SEMLSRN2UXE_1.html

Proposed Mission 2008: Europa vs. Titan Equal promise of scientific study Europa was chosen - mission was easier and less risky; included only an orbiter Europa life would be similar to oceanic Earth life Titan holds very different possibilities for scientific discovery Life would be exotic Similar chemical processes as those on Earth exist, but under extremely different conditions

Our Mission Two parts Transport Drop off blimp and rover http://www.space.com/1189-outer-planet-palooza-europa-titan-missions-support.html Two parts Blimp Amphibious rover Transport 7 year trip to Titan Spacecraft with simple cruise stage Drop off blimp and rover Cost – 2.5 Billion http://en.wikipedia.org/wiki/File:Duck_Tour_boat_beaching.JPG

Our Mission Blimp Objectives Design: Aerobot Sample atmosphere Gas chromatograph and mass spectrometry Tunable diode laser Scan and map surface Cameras, radar altimeter Observe climate and weather differences Meteorology instruments Design: Aerobot Transmitter to Earth, receiver for rover Life span 1-1.5 years, possibly longer Power: Radioisotope Thermoelectric Generator (MMRTG) Applications to life theory Accurate measure of hydrogen concentration differences Measure of methane concentrations to locate sources

Our Mission Rover Criteria Withstand atmospheric pressure, extreme cold and weathering; float on liquid methane Objective - Explore surface hydrocarbons and liquid methane Understanding of solid and liquid surface composition – 3 months Probe Mass spectrometry Chemical analysis Seismometer – liquid subsurface ocean? Cryovolcanism? Ongoing observations Search for life components Catalysts or unidentifiable compounds Microscopic and Macroscopic imaging

Our Mission Repercussions Environmental contamination Damage to landscape Avoid rover dying in lake Disruption of atmosphere From gases in blimp, skewed results from leaked gas

Supplementary Cost Slide www.lpi.usra.edu/opag/TitanEnceladusBillionDollarBox.pdf