Deep Impact By: Ashley King
Visual obstruction of the edge of the comet by the ejecta T= 0.001(s) T= 1.747(s) T= 5.482(s) T= 3.615(s)
Comparing light intensity before and after impact Line A, t= 1.747(s) Intensity after Impact Ejecta Fit is subtracted out W/[m^2 sr um] Fit 2 Fit 1 Intensity of edge before impact (I0) I/I0 = e^(- τ ) τ = Optical Depth Final Intensity (I) Pixel
Graph of the results: Line A Fit 2 Fit 1 ext I/I0
Graph of the results: Line D Fit 2 Fit 1 I/I0
Conclusions The data will be used to determine properties of the cometary nucleus: • Determine stratification in the nucleus • Resolve where the ice lies • Use reflectivity derived from brightness and optical depth Current research indicates : • Layered nucleus evidenced by appearance of rayed ejecta (Schultz et al., 2005) (A’Hearn et al., 2005) • the water ice lies within the first few centimeters to meters below the surface (Groussin et al., 2007)
Works Cited A’Hearn, M. F., M. J. S. Belton, W. A. Delamere, J. Kissel, K. P. Klaasen, L. A. McFadden, et al.: 2005, Science310, 258. Groussin, O., M. F. A’Hearn, J.-Y. Li, P. C. Thomas, J. M. Sunshine, C. M. Lisse, et al.: 2007, Icarus187, 16. Schultz, P. H., C. M. Ernst, J. B. Anderson: 2005, Space Sci. Rev. 117, 207.