Approximately how long would it take to send a message from earth to, and receive a confirmation from, a spacecraft orbiting Jupiter, if the planets are in alignment with the sun?
Radio waves travelling at 300,000 km/second would take approximately 35 minutes to reach a satellite orbiting Jupiter depending on alignment, and the same time to travel back to Earth, equaling about 1.2 hours. Jupiter's mean distance from the Sun is @ 783 million km., subtract 16 minutes for the time radio waves travel from the Earth to the Sun, and go from there.
The math:
(783 million km (distance to Jupiter from the Sun) divided by 300,000km per second (speed of light)= 2610 seconds, divided by 3600 (seconds in an hour) = approximately .725 hours, minus .13 hours (8 minutes from radio signals to and from the Sun) =.59 hours, times 2 (round trip radio wave) = approximately 1.18 hours if Earth and Jupiter are in alignment with the Sun.
More Info:
www.qrg.northwestern.edu