PROJECT ASSUMPTIONS SA SAROBI mission to to Tita tan Exploring - - PowerPoint PPT Presentation

S A A R R O B I I

MISSION TO TITAN

SA SAROBI mission to to Tita tan

Exploring the mysteries of the moon’s possible life and icy crust

PROJECT ASSUMPTIONS

MISSION CHECKLIST:

• analysing geological content ✔
• verification of the artificial life hypothesis ✔
• drilling into the surface of titan ✔

BIOCHEMISTRY OF TITAN

• Surface area: 8.3×107 km2
• Gravity: 1.352 m/s2 (0.14g)
• Temperature: 93.7 K (−179.5 °C)
• Surface pressure: 146.7 kPa (1.45 atm)
• Atmosphere composition:
• Stratosphere: 98.4% nitrogen (N2), 1.4% methane (CH4), 0.2% hydrogen (H2);
• Lower troposphere: 95.0% N2, 4.9% CH4

BIOCHEMISTRY OF TITAN

• dissociation of the atmospheric N2 and CH4 creates an array of
• rganic molecules in Titan’s atmosphere
• these produce a solid organic haze in the upper atmosphere

that obscures to the lower atmosphere and surface

• ethane accumulates on the surface and mixes with liquid

methane

Are they the key to understanding life on Titan?

ALTERNATIVE LIFE

• an article published in Science Advances in February 2015, conducted by

scientists from Cornell University, has suggested

the possibility of an alternative, nitrogen-based biochemistry

• it would be possible for a structure of liquid methane membranes to exist and rely on the

polarity of nitrogen-containing groups, identically as liposomes rely on the non-polarity of alkyl groups

cryogenic AZOTOSOMES might have the flexibility of a lipid bilayer

AZOTOSOMES

acrylonitrile

AZOTOSOMES

• azotosome begins the simulation as a grid of molecules
• self-assembles into its preferred structure
• good thermodynamic stability,
• high energy barrier to decomposition,
• area

expansion modulus similar to that

• f

phospholipid cell membranes in oxygen-rich solutions

• 10ppm concentration

lander containing drill and rover RTGs providing probe power low gain antenna high gain antenna

+

reaction wheels and monopropellant thrusters for attitude control radar altimeter and imaging cameras to map surface

airbags to cushion landing parachute will detach at low altitude to prevent canopy falling on the lander probe will scan surface of Titan in

• rder to find suitable landing spot

tetrahedral Landing platform means it will unfold to the correct orientation no matter which side it lands on

La Land nding ing

platform

antenna for communication with

• rbiting probe

ice-melting drilling device

Dr Drilling dev evice

features

heated side panels to reduce friction heated rotary drill head

• drilling device will use thermal heat from RTG or MMRTG

to heat both the drill head and side

• drill head will melt ice below the device while side

panels ensure good lubrication reducing friction and the possibility of getting stuck

• electrical energy will also be produced and

used to operate the rotary motion of the drill head allowing removal of debris and cutting action

• low

frequency will be used to communicate with the lander above ground and also to scan its surroundings drilling device also equipped with low frequency radar similar to that used to penetrate the ice in Greenland by NASA

• increased manoeuvrability and protection
• can move in any direction it wants allowing it to turn sharply

with no turning radius

• able to reach places that a typical rover would not be able to

traverse

• any impacts experienced by the rover will be dissipated more

evenly over the outer shell of the rover thus protecting its internal components from severe damage

• smooth profile reduces the chances of the rover getting stuck

total mass = 320kg diameter = 1m

Spherical configuration, beyond the typical wheeled rover design

ARMADILLO ROVER

ARMADILLO ROVER

Titan’s surface at the Huygens landing site, 10.2oS, 192.4oW. There are at least eight rocks visible in the image – numbered in red with size indicated for two of them. Distance from the lander is shown in blue. Rocks are thought to be H2O ice mostly coated by organic solid material.

Image from ESA

internal cage will rotate through all three axes through the use of 3 sets

• f wheels
• uter cage will be made
• f see-through mesh, to

enable camera vision from the interior small spikes anchored on the

• uter cage will provide the

rover with additional friction and impact protection

Ar Armadillo illo rover ver

features

• uter shell which rotates freely and

an inner cage housing all internal components

• for purpose of analysis 2D circle of same diameter considered
• simplify problem into two point masses
• outer shell mass positioned at centre of circle due to

uniformity

• mass of internal components with an undetermined position

mass of the outer shell CoG 𝐷𝑝𝐻 = ∑ 𝑁𝑝𝑛𝑓𝑜𝑢𝑡

• 𝑈𝑝𝑏𝑚 ¡𝑁𝑏𝑡𝑡
• Fig1. Calculate CoG using center of circle as datum

𝜄 = cos56 𝑒𝑗𝑡𝑞𝑚𝑏𝑑𝑓𝑛𝑓𝑜𝑢 ¡𝑝𝑔 ¡𝐷𝑝𝐻 𝑠𝑏𝑒𝑗𝑣𝑡 Fig1.5. Calculate maximum gradient

𝜄

ARMADILLO ROVER

mass of the inner shell + components

• assume uniform displacement over a segment of the circle

parameterized by its radius r, and angle alpha

• equation in figure 3 gives distance of the center of gravity
• f the segment and therefore the position of the internal

component point mass

• we will assume radius of segment is 0.45m to fit inside 1m

radius with room left for rotation mechanism

• Fig3. Mass Distribution over Segment

4𝑠 ? si n( 𝛽) 3(2𝛽 − si n( 2𝛽))

• Fig4. Position of Centre of Gravity

CRITICAL ANALYSIS

• Fig5. Alpha of segment vs Maximum Gradient
• inner mass 50% of total mass
• with an alpha value of 62.2 degrees a maximum

gradient of 20 degrees can be achieved

• if we increase the proportion of the total mass that

is inside the rover then we can distribute the mass

• ver a larger segment with the same maximum

gradient

• eg. at 60% inner mass, 20 degree gradient achieved

with alpha of 74 degrees

• larger values of alpha will make designing the

internal components easier

• this will also help with heat dissipation

CRYTICAL ANALYSIS

three sets of wheels for each axis of rotation allowing internals of rover to rotate freely within

• wheels will be able to move in and out to engage

and disengage contact with the outer shell

• only one set of wheels in contact with outer shell

at any one time wheel actuator

• uter shell

ARMADILLO ROVER

internal cage will rotate through all three axes through the use of 3 sets

• f wheels
• uter cage will be made
• f see-through mesh, to

enable camera vision from the interior small spikes anchored on the

• uter cage will provide the

rover with additional friction and impact protection

Ar Armadillo illo rover ver

features

• uter shell which rotates freely and

an inner cage housing all internal components

bottom of the internal cage will be filled with analytical equipment of geological and biochemical nature (represented in red) top of the internal cage will serve as the navigation centre with a camera and topographical mapping tool

EQUIPMENT

• ORBITRAP mass analyser and spectrometer
• infrared camera in the top hemisphere of the

rover

• meteorology and physical properties package
• robotic

arm with a small drill and a heating surface

• biochemical

analysis chamber with dried nanoparticles

• https://www.atsdr.cdc.gov/toxprofiles/tp125-c6.pdf

BIOCHEMISTRY OF TITAN

• search for a ‘polymeric information molecule’ for life in Titan liquids remains an
• pen research topic
• polyethers are a possible model for DNA substitute in non-polar hydrocarbon

solvents

• a two-letter code involving hydrogen bonding with polar molecules

containing O and N

• the structural substitutes for proteins might include hydrocarbon chains,

aromatic ring structures, carbon nanostructures, including graphene

BIOCHEMISTRY OF TITAN

• a set of biomolecules compatible with low-temperature methane and ethane liquids

could be capable of the same sort of ecological communication and exchange that

• ccurs on Earth
• signalling molecules = low-molecular weight hydrocarbons that would be mobile in the

Titan liquid

• a Titan analogue to viruses could be possible with hydrocarbon shells

encasing raw Titan genetic polymers that attach and then insert the genetic polymers into host organisms

• previous experiments suggested that hydrogen cyanide molecules often link

together to form a compound known as polyimine

• might support prebiotic chemistry in the ultracold temperatures on Titan
• can absorb a wide spectrum of light, including wavelengths that can penetrate

Titan's smoggy atmosphere

• has a flexible backbone
• it can adopt several different structures, from sheets to more coiled shapes

POLYIMINE

• polypyrrol – asymetric artificial muscles
• polyamine – conducting polymer useful for electrical components

such as transistors

• oxygen from ice and methane – heat generation by combustion

reaction

One day – building a lab on Titan to redesign the way we think of Biology and Chemistry?

FUTURE

S A A R R O B I I

MISSION TO TITAN

• th

the greate ter th the di displacement of

• f th

the inte ternal ma mass, th the greate ter th the tr traversable gra gradient

• additi

tional assumpti tions in in fi figure 1:

• inte

ternal components ts acco account fo for 50 50% of

• f to

tota tal ma mass

• Fig2. Inte

ternal Mass Displacement t vs Maximum Gradient

CRITICAL ANALYSIS

Fi Fig7 . Inner Components ts Mass Percenta tage vs vs Maximum Gradient t with th Alpha at t 60 degrees Fi

• Fig6. Inner Components

ts Mass Percenta tage vs vs Maximum Gradient t with th Alpha at t 10 degrees

CRITICAL ANALYSIS

• Müller-­‑Wodarg, C. A. Griffith, E. Lellouch, T. E. Cravens. (2014). Titan: Interior, Surface, Atmosphere, and Space Environment (Cambridge University Press, Cambridge, UK), (14).
• Jayalakshmi, K. (2015). Extra-­‑terrestrial life based on methane possible on Titan show cell models. [online] International Business Times UK. Available at: http://www.ibtimes.co.uk/extra-­‑

terrestrial-­‑life-­‑based-­‑methane-­‑instead-­‑water-­‑possible-­‑show-­‑cell-­‑models-­‑1489947 [Accessed 31 Mar. 2017].

• Orgel, L. (1998). The origin of life—a review of facts and speculations. Trends in Biochemical Sciences, 23(12), pp.491-­‑495.
• Spaceengineerswiki.com. (2017). Oxygen -­‑ Space Engineers Wiki. [online] Available at: http://spaceengineerswiki.com/Oxygen [Accessed 31 Mar. 2017].
• Lorenz, R. D. (2000). Post-­‑Cassini Exploration of Titan: Science Rationale and Mission Concepts. JBIS, 53, 218-­‑234. Retrieved March 17, 2017.
• NASA. (2013). Multi-­‑Mission Radioisotope Thermoelectric Generator (MMRTG). Retrieved March 16, 2017, from NASA: http://mars.nasa.gov/msl/files/mep/MMRTG_FactSheet_update_10-­‑

2-­‑13.pdf

• John Hopkins University Applied Physics Laboratory. (2008). Titan Explorer Flagship Mission Study.
• Kuiper, G. P. (1944). Titan: A Satellite with an atmosphere. Astrophysical Journal, 378.
• Stevenson, J., Lunine, J. and Clancy, P. (2015). Membrane alternatives in worlds without oxygen: Creation of an azotosome. Science Advances, 1(1), pp.e1400067-­‑e1400067.
• NASA. (2013, 12 12). NASA's Cassini Spacecraft Reveals Clues About Saturn Moons. Retrieved from http://www.nasa.gov/jpl/cassini/saturn-­‑moon-­‑titan-­‑20131212.html
• NASA JPL. (2015, June 19). The Mysterious 'Lakes' on Saturn's Moon Titan. Retrieved March 10, 2017, from Jet Propulsion Laboratory:
• NASA, ESA. (2009). Titan Saturn System Mission Study Final Report.
• Niku, S. B. (2011). Introduction to Robotics: Analysis, Systems and Applications. Wiley
• Stofan, E., Lorenz, R., Lunine, J., Bierhaus, E. B., Clark, B., Mahaffy, P. R., & Ravine, M. (2013). TiME -­‑ The Titan Mare Explore. IEEE
• Sushil K. Atreyaa, E. Y.-­‑M. (2006, October). Titan's Methane Cycle. Planetary and Space Science, pp. 1177-­‑1187
• T.Owens et al. (1997, August). The Relevance of Titan and Cassini/Huygens to Pre-­‑biotic Chemistry and the Origin of Life on Earth. Huygens: Science, Payload and Mission.

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