Cassini's Last Earthly Date Was 10 Years Ago Today

Artist concept of Cassini spacecraft. Artist concept of Cassini spacecraft. Image credit: NASA/JPL
  • submit to reddit

August 18, 2009

PASADENA, Calif. - A decade ago today, NASA's Cassini spacecraft flew past Earth at a distance of 1,171 kilometers (727 miles) on its way to an appointment with the solar system's second largest occupant - Saturn.

Launched in October of 1997, Cassini required a grand total of four planetary flybys to provide the gravity boost it needed to get to the ringed world. A gravity boost uses a planet's mass and orbital speed to "boost" a spacecraft's velocity as it flies past. Prior to its Earth encounter, Cassini had flown past Venus on two occasions (April 26, 1998 and June 24, 1999). The Earth flyby on Aug. 18, 1999 gave Cassini a 5.5-kilometer-per-second (about 12,000-mile-per-hour) boost in velocity, speeding Cassini toward its final gravity boost target of Jupiter in December of the following year. The total effect of the probe's four planetary flybys -- two Venus, one Earth and one Jupiter - was an extra 21.44 kilometers (13.64 miles) per second of velocity for the spacecraft.

Cassini arrived at Saturn and was captured into orbit on June 30, 2004. Since then, it has been returning a wealth of data about the planet, its rings and its moons.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Cassini orbiter was designed, developed and assembled at JPL. JPL manages the mission for the Science Mission Directorate at NASA Headquarters in Washington.

More information about the Cassini mission is available at http://www.nasa.gov/cassini or http://saturn.jpl.nasa.gov.



Commotion at Ring's Edge May Be Effect of Small Icy Object NASA Cassini Images May Reveal Birth of a Saturn Moon

› Read more

In its next phase, NASA's Cassini spacecraft will perform 22 loops between Saturn and its innermost ring. Join in the Cassini Name Game

› Read more

Ocean Inside Saturn's Moon Enceladus NASA Space Assets Detect Ocean inside Saturn Moon

› Read more


Get JPL Updates
Sign Up for JPL UpdatesRegister today and receive up-to-the-minute e-mail alerts delivered directly to your inbox.
Sign Up for JPL Updates