Figure 5: Principal component analysis of the observations of the LCROSS impact.
From: Characterization of the LCROSS impact plume from a ground-based imaging detection
The four PCs containing unambiguous sources of variance in the observational data. All data points in the eigenvectors are represented by open diamonds and appear to be solid black where the diamonds overlap. (a) PC1 amplitudes show the most highly correlated image of the lunar landscape across all frames. (e) The PC1 eigenvector describes the variations in the dynamic range from frame to frame. (b) PC2 amplitudes show brightness variations from the largest-scale variations in atmospheric seeing. (f) The PC2 eigenvector describes the variations in the size of the PSF. (c) PC3 amplitudes show sub-pixel imperfections in image registration along a line approximately perpendicular to the foreground hill directly above the impact point. (g) The PC3 eigenvector describes the extent of the image offset in this direction. The PC4 amplitudes (d) and eigenvector (h) contain analogous information to PC3 but along a line approximately parallel to the same point on the foreground hill.
