View Detailed Launch Information - archived:

Mission Timeline: Launch - Archived

Launch phases begin when the spacecraft transfers to internal power on the launch pad and ends when the spacecraft is declared stable, healthy, ready to accept commands and the launch telemetry has been played back.

Rover A launched using a Delta II 7925 launch vehicle from Space Launch Complex 17A (SLC-17A) at the Cape Canaveral Air Force Station in Florida. Rover B launched using a Delta II 7925H launch vehicle from SLC-17B at the Cape. For details, see the launch vehicle in the spacecraft section.

Launch Periods for Spirit & Opportunity

Mission Open Close Arrival
Rover A June 5, 2003 June 24, 2003 January 4, 2004
Rover B June 25, 2003 July 15, 2003 January 25, 2004

To allow changeover of ground equipment at the launch pads, the two missions must be launched at least 10 days apart. There were two daily launch opportunities throughout both launch periods, providing a high probability of liftoff within the back-to-back MER launch periods. A constant arrival date is used for both rovers.

Major MER Launch Phase Activities

  • the liftoff and boost phase of the launch
  • insertion into a circular parking orbit
  • a coast period followed by additional launch vehicle burns necessary to inject the spacecraft onto a trajectory to Mars
  • separation of the spacecraft from the launch vehicle
  • initial acquisition by the Deep Space Network
  • verification of the initial spacecraft health and operating conditions
  • the verified execution of a minimal set of post-launch commands