Mentor: Timothy N. Titus2 Mars South Polar Residual Cap: Determining Heights and distributions of Swiss Cheese Features Eric O. Betz1,2 Mentor: Timothy N. Titus2 1Northern Arizona University 2United States Geological Survey

Mars Orbiter Camera MOC acquires high res. images of the SPRC Strange features dubbed Swiss Cheese CO2 determined to be thin overlying layer

Unit A: Quasi-circular depressions and mesas Swiss Cheese Unit A: Quasi-circular depressions and mesas

Curl Depressions: Bean or heart shaped depressions with ramp to feature floor

Unit B: Typically is smaller than and surrounds unit A in a variety of shapes

Fingerprint Terrain: Linear depressions capable of near uniformity across vast distances

Project Goals Determine the height of units A and B Determine distribution of units A and B Find the average height of the SPRC

Significance Porosity of the SPRC CO2 ice. Thickness of the SPRC CO2 veneer. Re-deposition of mass from CO2 retreat.

Photoclinometry Photoclinometry = Shape from Shade Turns 2D image into 3D Digital Elevation Map USGS ISIS photoclinometry program PC2D Problems- Albedo must be uniform

Results 8,484 Measurements of 181 DEMs

Unit A = Purple Curl = Red Fingerprint = Yellow Unit B = Blue Map Projected DEMs Unit A = Purple Curl = Red Fingerprint = Yellow Unit B = Blue Unit A = 8 ± 2.52m Curl = 5.3 ± 1.4m Fingerprint = 2.8 ± .46m Unit B = 1.9 ± .33m

Acknowledgements I also thank Glen Cushing for his direction and advice, as well as the United States Geological Survey and NASA for financial Support.

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