Mars may be a frozen red desert that at least appears devoid of life, but there still could be something lurking beneath the surface, and a way to (if it exists) find it.
Any hypothetical life form on Mars probably fled underground long ago. Deep lava tubes provide shelter that the brutal radiation pounding the surface can’t reach, but OrganiCam searches for organics and can fly into one of these tubes via drone. This camera operates like something straight out of Star Wars, zapping lasers at a target to see whether there are organics in that object. Organics would glow with fluorescence. While they don’t necessarily mean life, there would be organics in any fossilized or surviving life on Mars. This is why scientists need to investigate anything that glows.
“OrganiCam will enable mission success in selection of organic-rich sampling locations,” said OrganiCam team leader Roger Wiens in a study that was presented at the 50th Lunar and Planetary Science Conference.
OrganiCam spawned from ChemCam, which is already on Mars, and SuperCam, which is on its way there with the Perseverance rover. ChemCam rides around on the Curiosity rover’s mast, and pretty much plays a much more advanced form of laser tag with the regolith. It will aim at a particular rock or something else in the soil and then zap it with an infrared laser beam to create a superhot plasma. Elements in the regolith are revealed by the colors that show up in that plasma, and a camera that images the targets also gives scientists here on Earth an idea of the surface geology Curiosity is looking at. ChemCam’s observations have really supported the idea of Mars having been much more Earthlike in the distant past.
SuperCam can do everything ChemCam is capable of, except it also brings with it two mineralogy techniques that are going to give it a more accurate read on what compounds on Mars might be related to life. OrganiCam takes that to another level by searching for organics and biomolecules.
“OrganiCam operates on the simple principle that bio-materials on Earth have characteristically short fluorescence lifetimes that clearly distinguish them from inorganic mineral phosphorescence,” Wiens said.
Flashing its laser at a target, OrganiCam will be able to expose organics because they will pulse with light every 100 nanoseconds. Since they emit light much faster than non-organics, they will instantly stand out. It will use Raman spectroscopy to figure out what those biological materials actually are. Raman spectroscopy is used to make out the molecular structure and other properties of a certain material. When the laser aims at a target, any of the light hitting that target which is scattered at different wavelengths and shows up as different colors is a Raman Scatter. The high points in a Raman spectrum give away vibrations of molecular bonds that can tell observers what kind of molecules OrganiCam has found.
Because it is tougher, lighter, and more energy-efficient, with lenses that are highly resistant to radiation, OrganiCam could be flown into Martian lava tubes by drone. There is a greater chance of anything that is alive to be crawling around in there because salt water from lakes that have long since vanished has seeped into these immense caves. Because salt water doesn't freeze as easily as fresh water, and heat coming from the mantle of Mars may be keeping the water from freezing, that could be a boost for life. Or not. However, OrganiCam has been proven to be able to detect bacteria up to 20 billion years old.
So next time you start wondering whether there is or ever was life on Mars, start thinking in terms of “deep within” more than “out there.”