Re:That's just not right! Where's the mirror image (Score 1)

Yeah, kind of - each scan line is taken almost instantaneously (like a camera's shutter), then after a short delay the next line is taken. What you see in the next line is a question of how much the point the camera is pointing at has moved, and of any changes in what the camera is looking at. If it's flying over a piece of ground that's not moving then the result is a straighforward picture of that piece of ground (the displacement in time is irrelevant because the object hasn't changed during the period the picture was being captured) If it was pointing directly at the same point (or I should say line) on the ground while a (pretty big) mars rover drove past, each line would capture a different part of the rover and you'd end up with a perfectly decent picture of the rover (assuming it was moving with constant speed it wouldn't be distorted either) There's nothing to prevent either of these pictures being perfectly focussed and not at all blurred. Taking a picture of this fly-by is more complex because both the object and the camera are moving (admittedly this depends on your frame of reference, but let's keep this as simple as possible!). This is what leads to there being two images (mirror image as the object overtakes the camera, then normal image as the camera overtakes the object) in the frame, but the principle is the same - there's no reason to expect the picture to be blurred.