I managed to catch an astonishingly fast-moving prominence here. I imaged it for 1 minute runs at 5 minute intervals, but really this was too slow, it was changing so quickly, that shorter runs might have been better. It was moving visibly on screen, and 20 minutes after I first saw it it was dissipating into space. A rough calculation shows it was travelling of the order of 10,000 miles per minute, or 0.1% the speed of light. The frames are about 25% of the Sun’s diameter.