How long does it take to receive radio signals (pictures and other information) from the Cassini spacecraft?
Answer Dear Scott, Radio signals from Cassini take about three hours to come to Earth. This time would vary slightly depending on how far the spacecraft is while it is in orbit around Saturn and its moons. For comparison, it takes 2 1/2 seconds for radio signals to leave the moon (you can hear the pause when you listen to tapes of Apollo astronauts talking to Mission Control) and about 20 minutes for radio signals to leave Mars. This shows that before astronauts venture far from Earth, we’ll have to figure out different ways of communicating with them because a radio conversation from Mars or Saturn would be all but useless.
