In August 2012 the Curiosity rover, equipped with the ChemCam and its high-powered laser, landed on Mars, tasked with discovering whether the environment on the planet may once have had the right conditions to support life forms. The answer was a resounding “Yes!” – there are indeed regions on Mars that, in a distant past, could have supported the micro-organisms known as microbes.
Almost nine years after that historic landing, there is a new rover on the Red Planet, as part of the Mars 2020 mission: Perseverance, which made its landing on 18 February 2021. Its goal is to explore and study in detail Jezero crater – billions of years ago the site of a lake and river delta – for the actual signs of that past life, and to identify and collect samples of rock and dust, which could be brought back to Earth by the Mars Sample Return mission for further, more comprehensive study.
Collecting rock samples might sound like a relatively simple task, but Mars’s arid terrain and extreme atmospheric conditions make the mission extremely difficult. The average temperature on the planet is -63°C (compared to around 15°C on Earth), with summer highs on the equator of 20°C and night-time lows sometimes reaching -143°C! Mars rovers thus need to be designed to carry the equipment needed for the mission, but also to withstand not only the icy cold but also the extreme differences in temperature.
This time around, the rover’s high-performance equipment includes SuperCam, a kind of supercharged version of Curiosity’s ChemCam, providing imaging, mineralogy and chemical composition analysis.
At the heart of SuperCam is an even more powerful laser, designed – just as it was for Curiosity – by teams at Thales. Our long-standing expertise in the field of laser technology, combined with close and trusted collaboration with SMEs and local partners, allowed it to overcome the complex challenges that Perseverance will face in seeking out the organic compounds that could point to past life on Mars.
The red laser in the SuperCam heats and vaporises material; the light emitted by the plasma this creates can then be analysed, thus providing the means to ascertain the chemical composition of rock samples.
In addition, a green laser enables the determination of the molecular makeup of materials on the planet’s surface, through a technique called Raman spectroscopy, which is being tested for the first time on Mars. These twin technologies mean that the SuperCam is capable of identifying the chemical and mineral makeup of tiny targets, some as small as a pencil point, from over 20 feet (7 metres) away.
The Red Planet may be tens of millions of miles away, but the degree of minute precision that Thales’s laser technology provides may finally allow us to dream of getting an answer to the age-old question: “Is there life on Mars?”
All it will take is time…and a little perseverance.
SuperCam, which is the fruit of international co-operation, is one of the mission’s seven scientific instruments. Weighing in at a very compact 10kg, it is packed with high tech that combines five different measurement technologies. It is made up of three spectrometers (LIBS, RAMAN and infrared), a colour camera (the one on ChemCam was black and white) and a microphone, which will be used to analyse certain characteristics of rocks (hardness, for instance) by measuring the sound of the impact of the LIBS laser.