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"What makes the orbit of the earth in relation to the sun different to the orbitals that occur in atoms?"
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Surface Processes and Surface-Subsurface Transport on Europa
Project Investigators: Cynthia Phillips
Other Project Members
Lisa Grossman (Undergraduate Student)Antonia Hubbard (Undergraduate Student)Summary
This project looks at Jupiter’s moon, which has a subsurface ocean under its icy surface. We have three main components – we are studying images taken by the Galileo spacecraft, we are looking at different geological features to determine their potential to be involved in the vertical transport of material to and from the surface ,and we are studying one process, impact gardening by small micrometeorites that churn the surface, in detail.
Astrobiology Roadmap Objectives:
Project Progress
Chris Chyba, Cynthia Phillips, Kevin Hand- The project has two components. The first, an overview of the astrobiological potential of various geological features on Europa, is proceeding well – we are continuing the study of various proposed formation mechanisms for different feature types such as ridges, bands, and chaotic terrain. The second, a search for current geological activity by comparing Galileo images taken on different orbits, is also in progress. We have completed a first-stage search of the Galileo Europa images to find overlapping images, and are continuing to work on improving our automated search method to make sure that we find all possible comparison images. We have processed a number of comparison pairs, and are currently working on automated techniques for speeding up the comparison process. In addition, a related project to study impact gardening on Europa and its potential for surface – subsurface transport of potential biogenic materials has reached some interesting conclusions thanks to the input of undergraduate student Lisa Grossman from Cornell University who worked with Phillips at an REU student in 2007. The gardening depth on Europa is thinner than we thought, probably only about a centimeter. This means that sputtering will tend to win out over gardening, and that less material can be mixed down to Europa’s subsurface beneath the radiation processing layer to be preserved. The project resulted in a number of conference presentations, and a publication is currently in preparation.
We also received funding from the NAI DDF to include 4 extra students in our NSF-funded REU summer program that brings undergraduate students from around the country to the SETI Institute to do research in astrobiology (Figures 1, 2). The four students received a stipend, travel, and housing for the summer. The students were selected in a competitive process from a pool of over 100 applicants. The selected students were: 1) Matthew Levit, from La Salle University, who worked with Scott Sandford and Stefanie Milam of the NASA Ames NAI team on a project doing laboratory experiments with interstellar ice materials important for prebiotic organic chemistry, 2) Alicia Muirhead, from UC Santa Cruz, who worked with Janice Bishop on a project related to the surface composition of Mars using laboratory data and data from the CRISM instrument on Mars Reconnaissance Orbiter, 3) William Swearson, from University of North Dakota, worked with Hector D’Antoni and Jay Skiles of the Ames NAI team, on a project related to paleoclimatology and early Earth conditions relevant to the origin of life, and 4) Shicong Xie, from UC Berkeley, who worked with Friedemann Freund on a project related to the physics and chemistry of rock alteration. The students all will present a talk at the end of the summer summarizing their research, to which members of the SETI Institute and Ames NAI teams, and NAI Central, will be invited. The DDF funding also helped support Cynthia Phillips who ran the program.
Figure 1. The 2008 SETI Institute REU students on a field trip to Lassen Volcanic National Park to study extreme environments for life.Figure 2. REU student Efrosini Proios, from the College of San Mateo, worked on a microbiology project studying halophiles with SETI NAI Team PI, Rocco Mancinelli.Mission Involvement
GalileoWe are using data from the Galileo spacecraft.Outer Planets Flagship candidate mission to EuropaCo-I Phillips is serving as an advisor to the science definition team for this mission.Cross-Team Collaborations
As part of our REU summer student program in astrobiology, we received funding from the NAI DDF to include 4 extra students, two from the SETI Institute team and two from the NASA Ames team. We have worked closely with Ames team members Scott Sandford, Hector D’Antoni, and Jay Skiles for the last two years as they have supervised students under this program.
Publications
Chyba, C.F. & Phillips, C.B. (2007). In Planets and Life: The Emerging Science of Astrobiology. Cambridge. Cambridge Univ. Press.
Hand, K.P. & Chyba, C.F. (2007). Empirical contraints on the salinity of the europan ocean and implications for a thin ice shell. icarus, 189:424-438.
Moore, J., Phillips, C.B., Sullivan, R., Spencer, J., Black, G. & Buratti, B. (2008 (submitted)). Surface Properties, Regolith & Landscape Degradation. U. Arizona Press.
Phillips, C.B. & Grossman, L.A. (2008). Impact Gardening on Europa. The Science of Solar System Ices: A Cross-Disciplinary Workshop:LPI Contribution #1406. LPI, Houston.
- Abiotic Nitrogen Cycling
- Expanding the List of Target Stars for Next Generation SETI Searches
- Formation of Nitrogenated Aromatics in the Interstellar Medium
- Iron, the Oxygen Transition, UV Shielding, and Photosynthesis
- Planetary-Scale Transition from Abiotic to Biotic Nitrogen Cycle
- Surface Processes and Surface-Subsurface Transport on Europa
- The High Lakes Project (HLP)
- Training for Oxygen: Peroxy in Rocks, Early Life and the Evolution of the Atmosphere
- “Are We Alone?” weekly science radio show