Scientists at JPL in California will attempt one of the most difficult landings in space history Sunday night.
The mars rover 'Curiosity' will need a precise landing on the Red Planet.
"Curiosity is the largest rover ever sent to another planet; it's about the size of an SUV."
Space historian Robert Zimmerman says there'll be a lot of nervous scientists in the control room.
"The rover itself is going to be lowered below the rockets on cables and gently placed on the ground by the unit and then the rocket part will release the cables and fly away."
Needless to say, this will require perfect calculations and perfect remote control.
Landings of much smaller rovers have been much easier. They've been bounced to the surface in protective shells.
If successful, Curiosity will collect samples and look for water on Mars -- possibly for decades.
