Mars and Titan's atmosphere and interior
Lead Research Organisation:
University of Oxford
Department Name: Oxford Physics
Abstract
Mars and Titan (Saturn's largest moon) are the two most Earth-like bodies in the solar system. Both planets have been suggested as possible locations for biological activity, either in the past, present, or future. What type of organisms might exist and whether they do exist is the topic of intense scientific debate and research. If life is found on another planet, it would have far reaching effects on the way we view our place in the universe and be one of the greatest scientific discoveries of all time. To understand the type of life that could occur on these bodies, and how we might look for it, requires in-depth knowledge of the environment of each planet. This is what I plan to focus my research on - in collaboration with major world-wide institutes such as NASA and ESA. Mars has a thin CO2 atmosphere and many surface features in common with Earth - e.g. river valleys (now dry) and sedimentary rocks. Recent evidence shows Mars was much more hospitable in the past with warmer temperatures and a thicker atmosphere, similar to Earth's early atmosphere. New results from NASA's Mars Exploration Rovers show evidence for prolonged existence of liquid water on the surface. Key to understanding this early environment is Mars' internal structure as this determined much about the surface of young Mars, including protection of the atmosphere from solar radiation, volcanoes which may have supplied much of the atmospheric gases, and interior convection/heat-flow which influenced surface geology. Knowledge of Mars' interior is currently very limited - we do not even know how big Mars' core is and whether it is liquid or solid. The best way to probe the interior is with seismology, as we do on Earth. The ExoMars mission includes a seismometer, which will use Marsquakes to probe the interior. I will calibrate and test the seismometer to ensure that the data can be interpreted properly, while simultaneously developing seismic models of Mars' interior using techniques modified from those developed for global seismology of Earth. Also key to understanding Mars' past environment is understanding the present atmosphere and climate change. It is not known if Mars' current climate is stable - water vapour migrates away from the poles each Martian summer and it is not known if it returns. One exciting possibility is that Mars is changing from one climate state to another. This question can only be answered with a combination of spacecraft and telescope observations. NASA's Mars Reconnaissance Orbiter (MRO) spacecraft is the latest and most advanced to enter orbit around Mars. I will use data from MRO to determine water and dust distribution in Mars' atmosphere and determine what effect these have on climate. Titan is an example of an Earth-like planet in the cold outer solar system. Titan has a thick atmosphere and has clouds and rain just like on Earth, but made of methane instead of water. The recent Cassini mission has shown many fascinating surface features including, methane lakes, valleys, volcanoes, and sand dunes made of tiny ice crystals. Titan's atmosphere is a breeding ground for organic molecules like benzene. Some very complicated molecules are expected to exist at the North pole, where they are protected from destruction by sun light by Titan's shadow. Cassini performed multiple flybys over the pole during 2006-2007, giving us our first ever view of this exciting region. Many of the organic molecules present in the measured infra-red spectra are yet to be identified. The global distribution of organic molecules can be used to probe Titan's atmospheric motions like the polar vortex and planet-wide circulation cells. Titan's spring equinox is in 2009 when models predict extensive and rapid changes in the atmosphere - especially at the winter pole. This pole is never visible from Earth and Cassini provides a unique opportunity to observe the polar vortex break-up, which will not be possible again for at least 30years.
Publications
Coustenis A
(2010)
Titan trace gaseous composition from CIRS at the end of the Cassini-Huygens prime mission
in Icarus
De Kok R
(2010)
A tropical haze band in Titan's stratosphere
in Icarus
De Kok R
(2008)
Condensation in Titan's stratosphere during polar winter
in Icarus
Fletcher L
(2009)
Methane and its isotopologues on Saturn from Cassini/CIRS observations
in Icarus
Fletcher L
(2009)
Phosphine on Jupiter and Saturn from Cassini/CIRS
in Icarus
Fletcher LN
(2008)
Temperature and composition of Saturn's polar hot spots and hexagon.
in Science (New York, N.Y.)
Jennings D
(2008)
Isotopic Ratios in Titan's Atmosphere from Cassini CIRS Limb Sounding: HC 3 N in the North
in The Astrophysical Journal
Kleinböhl A
(2009)
Mars Climate Sounder limb profile retrieval of atmospheric temperature, pressure, and dust and water ice opacity
in Journal of Geophysical Research: Planets
McCleese D
(2008)
Intense polar temperature inversion in the middle atmosphere on Mars
in Nature Geoscience
Nixon C
(2009)
Infrared limb sounding of Titan with the Cassini Composite InfraRed Spectrometer: effects of the mid-IR detector spatial responses
in Applied Optics
Nixon C
(2009)
Infrared limb sounding of Titan with the Cassini Composite InfraRed Spectrometer: effects of the mid-IR detector spatial responses
in Applied Optics
Nixon C
(2009)
Titan's prolific propane: The Cassini CIRS perspective
in Planetary and Space Science
Nixon C
(2008)
Isotopic Ratios in Titan's Atmosphere from Cassini CIRS Limb Sounding: CO 2 at Low and Midlatitudes
in The Astrophysical Journal
Nixon C
(2008)
The 12C/13C isotopic ratio in Titan hydrocarbons from Cassini/CIRS infrared spectra
in Icarus
Teanby N
(2009)
Titan's stratospheric C2N2, C3H4, and C4H2 abundances from Cassini/CIRS far-infrared spectra
in Icarus
Teanby N
(2010)
Compositional evidence for Titan's stratospheric tilt
in Planetary and Space Science
Teanby N
(2008)
Titan's winter polar vortex structure revealed by chemical tracers
in Journal of Geophysical Research: Planets
Teanby N
(2009)
Intersection between spacecraft viewing vectors and digital elevation models
in Computers & Geosciences
Teanby N
(2009)
Small-scale composition and haze layering in Titan's polar vortex
in Icarus
Teanby NA
(2009)
Dynamical implications of seasonal and spatial variations in Titan's stratospheric composition.
in Philosophical transactions. Series A, Mathematical, physical, and engineering sciences
Vinatier S
(2010)
Analysis of Cassini/CIRS limb spectra of Titan acquired during the nominal mission
in Icarus
Description | Titan atmospheric circulation reversal Mars impact seismicity |
Exploitation Route | Titan and Mars research |
Sectors | Aerospace Defence and Marine Education Environment |
Description | Titan's atmosphere and Mars interior science |
First Year Of Impact | 2008 |
Sector | Aerospace, Defence and Marine,Environment |
Impact Types | Societal |
Description | Cassini |
Organisation | National Aeronautics and Space Administration (NASA) |
Department | Goddard Space Flight Center |
Country | United States |
Sector | Public |
PI Contribution | Data analysis and interpretation |
Collaborator Contribution | Data analysis and interpretation |
Impact | publications (see pubs section) |
Description | Cassini |
Organisation | National Aeronautics and Space Administration (NASA) |
Department | Jet Propulsion Laboratory |
Country | United States |
Sector | Public |
PI Contribution | Data analysis and interpretation |
Collaborator Contribution | Data analysis and interpretation |
Impact | publications (see pubs section) |
Description | Cassini |
Organisation | Observatory of Paris |
Country | France |
Sector | Academic/University |
PI Contribution | Data analysis and interpretation |
Collaborator Contribution | Data analysis and interpretation |
Impact | publications (see pubs section) |
Description | Cassini |
Organisation | SRON Netherlands Institute for Space Research |
Country | Netherlands |
Sector | Academic/University |
PI Contribution | Data analysis and interpretation |
Collaborator Contribution | Data analysis and interpretation |
Impact | publications (see pubs section) |
Description | Cassini |
Organisation | University of Oxford |
Department | Department of Physics |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Data analysis and interpretation |
Collaborator Contribution | Data analysis and interpretation |
Impact | publications (see pubs section) |
Description | GSFC |
Organisation | National Aeronautics and Space Administration (NASA) |
Department | Goddard Space Flight Center |
Country | United States |
Sector | Public |
PI Contribution | Analysis and interpretation of spacecraft data |
Collaborator Contribution | Publications and access to data |
Impact | Contributions to 25 scientific papers since 2006 |
Start Year | 2006 |
Description | JPL |
Organisation | National Aeronautics and Space Administration (NASA) |
Department | Jet Propulsion Laboratory |
Country | United States |
Sector | Public |
PI Contribution | Analysis and interpretation of spacecraft data |
Collaborator Contribution | Analysis and interpretation of spacecraft data for publication |
Impact | Publication of over 10 scientific papers |
Start Year | 2006 |
Description | Paris |
Organisation | Observatory of Paris |
Department | Laboratory for Space Science and Astrophysical Instrumentation |
Country | France |
Sector | Charity/Non Profit |
PI Contribution | Analysis and interpretation of spacecraft data |
Collaborator Contribution | Analysis and interpretation of spacecraft data |
Impact | Published over 15 papers on planetary atmospheres |
Start Year | 2006 |
Description | Cassini Research Highlights Website |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Primary Audience | Public/other audiences |
Results and Impact | Press release of science results N/A |
Year(s) Of Engagement Activity | 2009 |
Description | Interactive Mission Posters |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Primary Audience | Industry/Business |
Results and Impact | Helped create interactive posters for project engineers (JPL/NASA) Helped communicate importance of the engineers work in achieving science goals |
Year(s) Of Engagement Activity | 2008,2009 |
Description | School Teacher Placement Program |
Form Of Engagement Activity | Participation in an open day or visit at my research institution |
Part Of Official Scheme? | No |
Primary Audience | Schools |
Results and Impact | Two US school teachers accompanied me while observing Saturn at NASAs IRTF on Hawaii to observe/discuss observations and science. Helped to create new and exciting exercises for use in class |
Year(s) Of Engagement Activity | 2009 |