An interferogram shows the difference in ground location between two SAR images. The number of color bands, or “fringes,” in the image is proportional to the distance the ground has moved between the first and second image. The left image is the interferogram calculated between Dec. 18, 2020, and Dec. 30, 2020. The right interferogram is calculated between Dec. 29, 2020, and Jan. 4, 2021.