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Mission to Titan
Natalia Alvarez • Kelsey Bertamus • Michael Morgan • Talia Strait • Natalie Taylor
Bulk Characteristics of Titan
•Diameter: 5,150 km•Average Density: 1.88
g/cm3 •Surface Temperature:
97K•Surface Pressure: 1.5
bars•Theorized to have an
interior liquid layer composed of ammonia and water ice
Guide to Titan
• Titan parallels early Earth▫ Lakes, Atmosphere,
Clouds, Rain, Volcanoes, Plate Tectonics.
• Only other body in solar system known to harbor stable liquids on its surface. ▫ Weather cycle▫ Good indications for life
or at the very least, pre-earth conditions.
Atmosphere
• Only known moon with an atmosphere.
• 1.45 Denser than Earth’s▫ 1.19 times as massive.
• Result of volcanism or microbial life.
• Like a young planet Earth.▫ Research simulated
atmospheric conditions and were given the building blocks of life.
Rain on Titan
• Recorded evidence of methane rainstorms on Titan in 2010.
• Occurred over equator, rather than at poles.
• Replenishes methane lakes and river systems.
• Skepticism on whether this is any indication of life.
Methane Lakes
• Thanks to Triple Point and rain, Methane Lakes exist on Titan’s surface
• Only known terrestrial body other than Earth to have stable liquids on its surface.
• Not difficult to land.
Cryovolcano
• Winter, S Hemisphere. • Sotra Facula is a
cryovolcano▫ Emits water with
ammonium, or polyethylene, paraffin waxes, or asphalt. Possibly replenishes methane in atmosphere.
• Located at 12degrees S / 39.8 degrees W
• 235 km wide
Habitability of Titan
•Titan’s PHI is 0.64•Solid Surface
▫Evidence of tectonics•Atmosphere
▫Nitrogen and Hydrocarbons▫Believed to be similar to Earth’s atmosphere
before oxygen was introduced•Surface Liquid
▫Titan’s 93K surface temperature is directly above the triple point for methane (90.68K)
Triple Point
• The temperature and pressure at which the three phases (gas, liquid, and solid) of that substance coexist in equilibrium.
• Different changes in temp and pressure transform substance to ice, liquid, vapor.
• EARTH’S SURFACE: temps and pressures similar to the triple pt of WATER.
• TITAN’S SURFACE: temps and pressures similar to the triple pt of METHANE.
Image Source: http://www.nmij.jp/english/library/units/temperature/triple-chart_en.gif
Possibility for Methanogenic Life
•2005 – Chris McKay suggested that methane-based (rather than water-based) life on Titan could consume hydrogen, acetylene, and ethane – i.e. organisms called methanogens.
•EARTH = O2 metabolismImage Source: http://www.engr.ku.edu/images/media/methanotrophs.jpg
C6H12O6 (glucose) + O2 -> CO2 + H2O
Methanogenic Life (continued)
Titan’s organisms would:• Inhale H2
instead of O2• React it with acetylene (or
CO2) instead of glucose
• Exhale methane instead of carbon dioxideWater is widespread on Earth,
therefore life is widespread on Earth because it uses water.Analogous to Earth = Liquid methane lakes are widespread on the surface of Titan.
C2H2 (acetylene) + 3H2 -> 2CH4
Photo source: http://upload.wikimedia.org/wikipedia/commons/thumb/e/e8/PIA10008_Seas_and_Lakes_on_Titan.jpg/300px-PIA10008_Seas_and_Lakes_on_Titan.jpg
•TITAN= H2 metabolism
The Miller-Urey Experiment• The Experiment (1953):
▫ INORGANIC components ORGANIC components in conditions similar to pre-biotic Earth.
▫ Warm water + four gases [H2O, CH4, NH3, and H2] + electrical discharges▫ Formed simple organic molecules, including amino acids and RNA nucleotides. ▫ Formed the idea that on pre-biotic Earth there existed an abundance of RNA life
produced through chemical reactions.• In the search for extraterrestrial life? Helps to understand the conditions
required for life to form. • Titan’s atmosphere lacks oxygen, but complex organic molecules are present.
▫ Could form biological materials in a pre-biotic habitat resembling that of early Earth.
Photo source: http://www.chem.duke.edu/~jds/cruise_chem/Exobiology/Pmilurey.gif
Yellow = hazy surface of TitanLight gray = ice layer starting near the surfaceBlue = internal oceanLight gray = another layer of iceDark gray = mixture of rock and ice in the interior
Titan as a Prebiotic Environment?
• Possible host for microbial extraterrestrial life because of its pre-biotic-like environment rich in complex organic chemistry.
• Possibly subsurface liquid ocean serving as a biotic environment.
• Implications of a possible ammonia-water ocean inside Titan.
Past Mission: Cassini-Huygens
• NASA / ESA / ASI Spacecraft to study Saturn and its satellites.
• Launched in 1997, reached system in 2004
• Cassini: first to enter Saturn’s orbit.▫To study structure and
history of the rings and satellite surfaces.
▫Studies Titan’s cloud, hazes, and regional surfaces.
Huygens Probe
• Reached Titan Jan 14th, 2005• Sent data for 90 minutes after touchdown.• Designed to brake in atmosphere and parachute
a robotic lab to the surface.• Sent signals to Cassini to relay back to Earth.
Huygens Design
• Heat shield and parachute.• 6 Types of Instrumentation to
study:▫ Physical and electrical props of
atmosphere▫ Radiation balance in Titan’s
atmosphere▫ Chemicals in Titan’s
atmosphere▫ Volatiles and decompose
complex organic materials▫ Physical properties at point of
impact.
Huygens Findings
• Landed in “Titanian Mud”
• Rounded pebbles imply possible fluid motion.
• Dense cloud or thick haze ~ 18 – 20 km from surface.
Two New Proposals: TSSM and TiME
• Titan Saturn System Mission▫ Consists of an orbiter and
2 probes.▫ More features than
Huygens.• Titan Mare Explorer
▫ Land in and travel around a methane lake.
▫ To sample and analyze organics for 3 – 6 months.
▫ New power source: Advanced Stirling Radioisotope Generator.
Goals of TSSM & TiME
• Explore Titan as a system.
• Study Titan’s organic inventory and astrobiological potential
• Constrain Titan’s origin and evolution models.
• Recover information on Enceladus and Saturn’s magnetosphere.
Landing on TitanMission: PLOT
• Probe for Life and Organics on Titan• Land in Lake Ontario Lacus• Possibly explore nearby cryovolcano• Look for Evidence of Life: CO2, acetylene,
amino acids, enzymes, isotopic fingerprints▫ Use Cassini to relay back data
Landing on TitanAdvanced Stirling Radioisotope Generator
▫ Powerful generator currently being developed by NASA.
▫≥14 year lifetime ▫Mass ~ 20 kg▫Uses 0.8 kg plutonium-238▫ January 2015
Source: NASA
TestingTesting
• Mass Spectrometer• Composite Infrared
Spectrometer▫ Test for hotspots in lake
• MOD III• Seismometer• Camera
Image Source: NASA
Mission Target- Ontario Lacus
•Located at 72° S & 183°W
•Composed of methane, ethane, and propane.
•Volume: 7-50 km3
Ontario Lacus
Tour of Ontario Lacus
http://www.youtube.com/watch?v=kK4n5l7bHSw
TimelineTimeline
2017: Launch2024: LandThe goal is to land and test during winter in the Southern Hemisphere.
2017 2024
Cost of MissionCost of Mission
•Proposed Cost: 1 billion ▫ Includes cost of designing and launching a new
probe.▫ Use of the orbiter from the Cassini mission will
cut costs
• Cassini-Huygens mission (launched 1997)
cost NASA 3.2 billion!
Bibliography
… is expensive but IMPORTANT!
The Search for Life