CTYPE1 keyword: the pix-to-world projection type for the X axis. Whether to look for an X-axis unit. CUNIT1 keyword: the world unit for the X axis. CRPIX1 keyword: reference position in pixel coordinates, X axis. CRVAL1 keyword: reference position in world coordinates, X axis. CDELT1 keyword: the size in world coordinates of the X-axis pixel spacing. CTYPE2 keyword: the pix-to-world projection type for the Y axis. Whether to look for an Y-axis unit. CUNIT2 keyword: the world unit for the Y axis. CRPIX2 keyword: reference position in pixel coordinates, Y axis. CRVAL2 keyword: reference position in world coordinates, Y axis. CDELT2 keyword: the size in world coordinates of the Y-axis pixel spacing. CROTA2 keyword: the rotation angle (deg). Name of the dataset