On the night of Aug. 5, the MSL spacecraft will hit the Martian atmosphere going about 13,000 mph (21,000 kph). As it barrels through the Red Planet air, MSL’s heat shield will literally glow, reaching temperatures of about 2,900 degrees Fahrenheit (1,600 degrees Celsius).
The relatively thin Martian atmosphere will slow MSL down to only 1,000 mph (1,600 kph) or so, Rivellini said. So the spacecraft will also deploy a parachute, one that can withstand 65,000 pounds (29,500 kilograms) of force despite weighing just 100 pounds (45 kg) itself.
But even the parachute won’t be enough.
“This big huge parachute that we’ve got, it’ll only slow us down to about 200 miles per hour,” Rivellini said. “And that’s not slow enough to land. So we have no choice, but we’ve got to cut it off and then come down on rockets.”
The rockets can’t fire all the way to the ground, however, or they’d raise a huge dust cloud that could damage the rover’s instruments and mechanisms, researchers said. To avoid such a ruckus, Curiosity will be lowered to the Martian surface on 21-foot-long (6.4 meters) cables. When the rover is safely down, the cables will be released and the rocket-propelled sky crane will fly off so it doesn’t crash into Curiosity.
The 14-minute communications lag between Earth and Mars means that the MSL team won’t be getting real-time updates about the rover’s perilous journey.
“When we first get word that we’ve touched the top of the atmosphere, the vehicle has been alive, or dead, on the surface for at least seven minutes,” Steltzner said.
If this works, I will be VERY impressed...