What were the fastest speeds reached by the Cassini spacecraft?
The maximum speed clocked by Cassini was 44.0 kilometers per second (98,346 miles per hour) relative to the Sun on June 25, 1999. Relative to Saturn, the spacecraft reached 30.7 kilometers per second (68,771 mph) during the Saturn Orbit Insertion maneuver on July 1, 2004. With respect to Earth, the maximum speed reached by Cassini is 19.0 kilometers per second (42,561 mph) on Aug. 18, 1999, as the spacecraft flew past our home planet at an altitude of 1,171 kilometers (727 miles). During the second Venus flyby, Cassini zoomed by the planet at 13.6 kilometers per second (30,523 mph) on June 24, 1999. The spacecraft flew by Jupiter at a speed of 11.6 kilometers per second (25,951 mph) on Dec. 30, 2000.
