QUESTION:
How large (in bytes) are the pictures from Mars and how long do they take to
download from Mars?

ANSWER from Robert Manning on July 22, 1997:
The image (frame) sizes sent down to Earth vary considerably for two
reasons. First, the size of the frame that the IMP (Imager for Mars
Pathfinder) takes is oftentimes "windowed" to only a small portion of the
full 256x256 pixel image frame (12 bits per pixel). Second, as a rule we ask
the lander's on-board software to digitally compress the image so that the
number of bits we need to send down is greatly reduced (often by more than 6
to 1). So a typical 14 degree square frame is roughly about 256x256x12/6
bits or 130,000 bits per frame. An image of this size takes about 15 seconds
at the highest downlink data rate we can use which is 8295 bits per second.
This corresponds to about 4 frames per minute. (Don't confuse this time with
the own-way light time which is currently just over 11 minutes.) Of course
to take a wide angle color panorama takes hundreds of frames.