Curiosity's tools for exploration
Sen— NASA’s Curiosity rover successfully landed on Mars yesterday to begin a two year mission to explore the Red Planet. Once engineers have confirmed that all systems are operating during the first drive phase of the mission, Curiosity will use an impressive array of instruments to determine if habitable conditions ever existed on Mars.
There are ten scientific instruments aboard the car-sized rover, consisting of cameras and spectrometers in order to analyse the surface in exquisite detail.
Curiosity can capture HD video and high resolution images using Mastcam. Mastcam consists of two cameras, and the right “eye” uses a telephoto lens, while the left eye used a medium-angle lens. Mastcam comes equipped with a filter that will allow the rover to peer skywards directly at the Sun. This can be used to measure the amount of dust in the Martian atmosphere.
A camera that can be used for detailed close-ups is located at the end of Curiosity’s robotic arm. The Mars Hand Lens Imager (MAHLI) can be used for close up views of interesting rocks, as well as allowing Curiosity to take self portraits. MAHLI can be used to measure the sizes of grains in rocks, which can yield important information as to how the grains were transported and deposited.
A schematic showing the position of the instruments aboard the Curiosity rover. Credit: NASA/JPL-Caltech
The Mars Descent Imager (MARDI) was used to video Curiosity’s dramatic descent to the red planet. Images taken during the descent are of a higher resolution than is currently possible from spacecraft in orbit.
The Dynamic Albedo of Neutrons (DAN) experiment has the ability to seek out hydrogen up to half a metre below the surface. Hydrogen is indicative of water ice, and DAN can detect the hydrogen by shooting neutrons at the ground and measuring their energy as they are reflected.
Curiosity has its own weather station, called the Rover Environmental Monitoring Station (REMS). REM will take measurements for five minutes of every hour, leading to a detailed knowledge of the atmosphere which will yield clues as to the habitability of Mars.
The Sample Analysis at Mars (SAM) experiment will seek out the complex carbon compounds that are the building blocks of life. While these are not solely formed by life, they are essential for life as we know it. These compounds were not detected by the Viking experiments in 1976; however Curiosity has a much greater sensitivity, as well as having the ability to wander around the red planet, making detection more likely. The tunable laser spectrometer, which is a part of SAM, is sensitive enough to detect any methane on Mars. Methane can be created by microbes, and there have been tentative reports of methane on Mars, which the spectrometer should be able to investigate further. A firm detection of methane doesn’t necessarily mean that microbial life exists however, as methane can be produced by other sources.
A laser will be fired at rocks by the Chemistry and Camera suite, or ChemCam, to determine elements in rocks and soil. Zapping rocks with a laser produces a spark which is then measured by the telescope on top of Curiosity’s mast. The laser can target rocks up to seven metres away in order for ChemCam to identify the elements in the rock.
The Alpha Particle X-Ray Spectrometer (APXS) shoots a sample of radiation, instead of a laser, at a rock until it emits X-rays at a particular wavelength that will identify the element. APXS has its own cooling system, as X-ray detector chip needs to remain cold, meaning that the instrument can be used day and night. The Mars Exploration Rovers had similar technology but without the cooling system, so it could be used at night. The APXS aboard Curiosity is also a much more sensitive instrument than those aboard Spirit and Opportunity.
Minerals capture details of their environment as they form, so that the Chemistry and Mineralogy experiment, or CheMin, can evaluate the environmental history of Mars. It does so by looking at the temperature, pressure, and chemistry of minerals. CheMin measures how X-rays are diffracted, or scattered, from a sample which is used to identify the elements present. Curiosity is the first Mars rover to use an X-ray diffraction instrument.
The Radiation Assessment Detector (RAD) will measure radiation levels on Mars. RAD will determine just how damaging radiation can be to any microbes that might be near the surface. RAD has already been put to good use en route to Mars, as it has measured the radiation levels in interplanetary space. Knowledge of the potentially lethal levels of cosmic radiation is important if we are ever to send astronauts to Mars.
Curiosity has a primary mission of 98 weeks in which to utilise its innovative instruments to explore Mars.