Having successfully negotiated the dreaded "seven minutes of terror" to complete its Mars landing, NASA's newest Red Planet rover, Curiosity, will soon begin its mission to search for signs of past life on Mars. The rover is outfitted with a drill and scoop, a robotic arm, and 10 scientific instruments to collect and analyze rock and soil samples from a variety of the planet's sedimentary layers in an attempt to determine whether past conditions on Mars were favorable to microbial life and whether, in fact, such life ever existed there.
While scientists don't know what they will find, speculation abounds. It's highly unlikely that Curiosity will detect anything as obvious as actual microbes or vegetation, but the rover will be looking for evidence of water and other essential ingredients for life as we understand it. Whatever Curiosity finds, it will greatly enhance our scientific knowledge of the planet and better prepare us for future missions, such as the long-hoped-for human visit to Mars.
Shortly after landing, Curiosity began sending back black-and-white images of its immediate surroundings. One photo captured the rover's own shadow on the surface of the planet, truly an inspirational sight. As planned, Curiosity touched down near the base of Mount Sharp, a 3-mile-high mountain within the Gale Crater, located in the planet's southern hemisphere.
After going through a series of checks to make sure all its systems are functioning properly, Curiosity will set out to climb Mount Sharp, a journey that is expected to take two years. Along the way, the rover will examine the various layers of rock that make up the mountain with its array of scientific instruments. One of the coolest of these fires a laser beam at rocks to check their elemental composition from a distance. The rover will use its drill and scoop to collect samples, then analyze them inside the rover.
Because it takes 15 minutes for signals to travel between Mars and Earth, scientists cannot control the rover in real time. Instead, all the rover's instructions are pre-programmed and sent in batches, and the scientists then have to wait to see how it all works out before preparing and sending the next batch of instructions. This is a process that can be both tricky and frustrating, but the experts at NASA and the Jet Propulsion Laboratory have had years of experience working with Curiosity's forerunners, Spirit and Opportunity, which have been on Mars since 2004. Spirit stopped communicating in 2010, but Opportunity is still operating.
Curiosity is the fourth NASA rover to succeed in a Mars landing. The first was Sojourner, which landed in 1997. With its extensive scientific payload, Curiosity is five times more massive than the 2004 rovers, and twice as long. The Mars Science Laboratory, as the mission is officially named, is designed to run for two years, but if it works as well as Spirit and Opportunity, it could well be running far longer, sending back new and fascinating information for scientists on Earth to interpret for many years to come.