1. Mitchell Drew and Mariel Henkoff
Mission to Titan
Mitchell Drew and Mariel Henkoff

2. 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

3. 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

4. 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

5. 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

7. 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

8. 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

9. 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?

10. 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

11. Cassini-Huygens Huygens Probe
Transmitted information for 2.5 hours while descending through atmosphere
~70 minutes on surface

12. 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

13. Our Mission Two parts Transport Drop off blimp and rover
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

14. 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 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

15. 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

16. 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

17. Supplementary Cost Slide