Curiosity and the Mars Science Laboratory Mission

Landed on Mars: August 6 at 1:32 a.m. Eastern (August 5, 10:32 p.m. PDT)

NASA has taken a bold new step in the exploration of Planet Mars with a new rover called Curiosity (centerpiece of the Mars Science Laboratory mission). Curiosity will seek to determine if the Red Planet ever had conditions to support life. Launched from Cape Canaveral on November 26, 2011, Curiosity carries a Canadian-made geology instrument that will enable the rover to determine the chemical composition of the rocks and soil on Mars.

The mobile lab will be equipped with ten different instruments, each with specialized capabilities to investigate different aspects of the rocks and soils or the current environment of the planet. Compiling the data from all the instruments will help scientists establish if Mars was once a more hospitable place for life.

Although recent missions led by Curiosity's predecessors have provided valuable data on the geological composition of our planetary neighbour, Curiosity will delve into Mars' environmental history in much greater detail than previous missions. This laboratory on wheels will act as a motorized field geologist and geochemist, probing and analysing the Martian surface using, among other things, its Alpha Particle X-ray Spectrometer (APXS) provided by the Canadian Space Agency (CSA). The spectrometer, specially adapted and tuned for the mission, will analyse samples to help ascertain the potential habitability of Mars.

APXS instrument

Roughly the size and shape of a Rubik's cube, APXS's sensor will be able to gather data day and night. It will take two to three hours to analyze a sample to determine what elements it is made of, including trace elements. A quick-look analysis can be completed in about ten minutes. APXS, which sits on the end of the rover's robotic arm, will move in close to a sample and bombard it with alpha particles (charged Helium nuclei) and X-rays to study the properties of the energy emitted from the sample in response. The APXS instrument on Curiosity is an updated version of the spectrometers that were successfully used on the Mars Exploration Rover (MER) and Mars Pathfinder missions.

APXS on Curiosity

A new generation of explorers

APXS will be accompanied by nine other science instruments on Curosity, including a hand lens imager and a panoramic camera. In comparison, the MER mission (known for its famous rovers, Spirit and Opportunity) had only five instruments on each rover. The size of a small car, the Curiosity rover is also much bigger than its predecessors. Nevertheless, Curiosity is an effective amalgamation of state-of-the-art laboratory instruments and MER-style mobility that will enable Curiosity to roam and explore the planet.

Due to the added capabilities and the big instruments in the rover's belly, Curiosity needs more energy to operate. It receives its energy from a thermoelectric generator that uses the decay heat from radioactive isotopes to generate about three times the amount of energy that a MER rover achieved under ideal conditions with its solar panels. This also means that Curiosity will be able to operate much better during the Martian winter, when the capabilities of the MER rovers were curtailed due to the low-standing sun.

The mission should last at least one Martian year, the equivalent of two Earth years. As with its predecessors on this desert planet, Curiosity will sleuth through the dust and rock historical archive of Mars' ancient environment in search for answers to a question that has fascinated humanity for ages: is there life out there in the Universe? Thanks to the APXS instrument, Canada will help scientists get a clearer picture of the answer.

The CSA is an international partner on NASA's Mars Science Laboratory mission, led by the Jet Propulsion Laboratory (JPL). Dr. Ralf Gellert of the University of Guelph is the Principal Investigator for APXS. He provided the scientific design based on the MER instrument (developed at the Max Planck Institute for Chemistry, in Mainz, Germany) and leads the APXS science team, which includes: the University of New Brunswick, University of Western Ontario, JPL, University of California, San Diego, Cornell University, the Rensselaer Polytechnic Institute and the Australian National University. MDA is the prime contractor for APXS.