“Tonight, on the planet Mars, the United States of America made history. The successful landing of Curiosity – the most sophisticated roving laboratory ever to land on another planet – marks an unprecedented feat of technology that will stand as a point of national pride far into the future. It proves that even the longest of odds are no match for our unique blend of ingenuity and determination. Tonight’s success reminds us that our preeminence – not just in space, but here on Earth – depends on continuing to invest wisely in the innovation, technology, and basic research that has always made our economy the envy of the world. I congratulate and thank all the men and women of NASA who made this remarkable accomplishment a reality – and I eagerly await what Curiosity has yet to discover.” - President Barack Obama, August 6, 2012

At 1:32 a.m. EDT on August 6, NASA’s Mars Science Laboratory (MSL) touched down on the Red Planet, beginning a two-year mission of exploration and discovery. The Curiosity rover is a mobile laboratory equipped with 10 science investigations and a robotic arm that can drill into rocks, scoop up soil, and deliver samples to internal analytical instruments. (For detailed information on Curiosity’s instruments, see the feature beginning on page 28.)

The spacecraft’s descent stage, while controlling its own rate of descent with four of its eight throttle-controllable rocket engines, begins lowering Curiosity on a bridle. The rover is connected to the descent stage by three nylon tethers and by an umbilical, providing a power and communication connection. The bridle extends to full length, about 25 feet, as the descent stage continues descending. Seconds later, when touchdown is detected, the bridle is cut at the rover end, and the descent stage flies off to stay clear of the landing site. (NASA/JPL-Caltech)

Following a harrowing “seven minutes of terror” in which Curiosity had to survive a dive that took it from 13,200 miles per hour to zero, the rover touched down and immediately began sending back images from its landing spot in Gale Crater.

Said MSL project scientist John Grotzinger, “Curiosity is not a life-detection mission. We’re not actually looking for life. We don’t have the ability to detect life if it was there. What we are looking for are the ingredients of life.”

MSL will study whether the Gale Crater area has evidence of past and present habitable environments. These studies will be part of a broader examination of past and present processes in the Martian atmosphere and on its surface.

Curiosity will rely on new technological innovations. For its landing, the spacecraft descended on a parachute and then, during the final seconds prior to landing, lowered the upright rover on a tether to the surface, much like a sky crane. Now on the surface, the rover will be able to roll over obstacles up to 29 inches high, and travel up to 295 feet per hour. On average, the rover is expected to travel about 98 feet per hour, based on power levels, slippage, steepness of the terrain, visibility, and other variables.

This full-resolution image shows part of the deck of Curiosity taken from one of the rover’s Navigation cameras looking toward the back left of the rover. On the left, part of the rover’s power supply is visible. To the right of the power supply is the pointy low-gain antenna and side of the paddle-shaped high-gain antenna for communications directly to Earth. (NASA/JPL-Caltech)

To make best use of the rover’s science capabilities, a team of scientists and engineers will make daily decisions about the rover’s activities for the following day. MSL is intended to be a discovery-driven mission, with the science operations team retaining flexibility in how and when the various capabilities of the rover and payload are used to accomplish the overall scientific objectives.

Curiosity landed in a region where a key item on the checklist of life’s requirements has already been determined: It was wet. Observations from Mars orbit during five years of assessing candidate landing sites have made these areas some of the most intensely studied places on Mars.

While the possibility that life might have existed on Mars provokes great interest, a finding that conditions did not favor life would also pay off with valuable insight about differences and similarities between early Mars and early Earth.

Learn more about Curiosity’s mission at http://mars.jpl.nasa.gov/msl .