On 6 August 2012 millions of people around the world watched the live feed of NASA’s Curiosity rover as it touched down on Mars. After making its 450 million kilometre journey from Earth to Mars, the rover had to decelerate from a speed of 20,000 km/h to zero in just fifteen minutes to effect a safe touchdown onto the Red Planet’s surface. It was by far the most complicated attempt to land on another planet that humans have so far attempted.
Dr Charles Elachi, JPL’s Lebanese-born director, puts the achievement into context.
“After that journey, we had to land within a circle of about one kilometre, because we needed to land in a very specific spot,” he says. “That’s the same as if I hit a golf ball from Los Angeles to Dubai, and it has to come straight in the cup — that’s how accurate we had to be. And to make it just a little bit more challenging, the cup is moving at high speed.”
In the end it went completely by the book. The JPL website received just over 1.8bn hits during the course of the next day, and President Barack Obama lauded the touchdown as “an unprecedented feat of technology that will stand as a point of national pride far into the future”.
For Elachi, the success of Curiosity marks just another step in an astonishing journey that has taken him from the Lebanese town of Zahle via university in France to Pasadena, where the JPL is headquartered.
One of NASA’s field centres, JPL’s brief is not only to build and operate planetary spacecraft, but to conduct astronomic investigations into star systems, as well as operating the global communications system that allows scientists here on Earth to talk to their spacecraft.
Curiosity’s arrival on Mars was not NASA’s first landing on the planet; two far smaller rovers, Spirit and Opportunity, touched down on Mars in 2003. But Curiosity’s brief is of a far greater magnitude.
The size of a small car, the rover is perhaps best described as a “mobile chemist”; not only can it collect samples, but it can also heat them in its onboard oven, allowing scientists to see what kind of material has been emitted.
That ability has already paid off. In early December, samples from a site called Rocknest showed complex chemical compounds in the Martian soil. If organic compounds are located, along with the presence of water, then the building blocks of life could be present on Mars.
The potential presence of life on other planets is one of JPL’s primary missions, says Elachi. When asked whether he thinks that life could exist on Mars, he certainly isn’t ruling it out.
“I would be pleasantly surprised, but we don’t know for sure,” he says. “There might not be life on the surface; it could be beneath the surface or it could be extinct. But that’s one of the key objectives for our exploration — in our solar system is there any way that life could have started?
“If we find life on other planets, that could give us an indication as to whether our kind of life is common — is everything based on DNA and carbon? Other kinds of life might be based on a different kind of structure. So that would give us insight into our own biological evolution.”