This week, NASA announced it was « excited » about finding something called organics on Mars.
Life, as we know it, is comprised of organic things, like carbon. Your body is teeming with carbon. So how excited should you be about the organics found on Mars?
We’ll let you decide. In short, the space agency’s hi-tech Perseverance rover — which is a car-sized laboratory on six wheels — collected valuable rock samples that contain organics. These rocks formed in a once-watery Martian place where life could have indeed thrived. It is an inarguably intriguing, compelling, and cool finding.
But it’s certainly not evidence of life. Not even close.
What NASA found on Mars
NASA is using the Perseverance rover to, among a variety of tasks, collect rock samples for a later mission to rocket back to Earth in the early 2030s. (The rocks will be stored in « ultra-clean sample tubes » to avoid contamination with earthly life.)
The space agency landed the robot in the Jezero Crater because it’s a place where microbial life — if it ever existed — could have evolved and flourished. This region of Mars contains a dried up river delta, a place where water once flowed from a Martian river into a lake. NASA’s planetary scientists think rocks collected there will give them a good shot at identifying indicators of past life (if, of course, it existed).
« The burden of proof for establishing life on another planet is very, very high. »
But don’t expect NASA to announce that the rover identified convincing evidence of life anytime soon. Those samples almost certainly must be carefully scrutinized on Earth to sleuth out such momentous, unprecedented evidence.
« The burden of proof for establishing life on another planet is very, very high, » Perseverance project manager Ken Farley recently said at a press conference.
This summer, NASA devoted special attention to a three-foot-wide rock they’ve named « Wildcat Ridge. » It likely formed in a saltwater lake, so the space agency zapped the rock with a specialized laser to reveal the chemicals on this ancient boulder. They indeed found « organic materials. »
But organic materials don’t mean life. Their main ingredient is carbon, along with elements like oxygen and hydrogen (sound familiar?), among others. They give planetary scientists a hint that a rock or area on Mars is a place that merits investigation.
« The presence of these specific molecules is considered to be a potential biosignature – a substance or structure that could be evidence of past life but may also have been produced without the presence of life, » explains NASA.
The space agency has found organics before. What makes the organic findings in the Jezero crater so « exciting, » however, is life might have survived in such a habitable river delta.
« The fact the organic matter was found in such a sedimentary rock – known for preserving fossils of ancient life here on Earth – is important, » NASA’s Farley said in a statement. « However, as capable as our instruments aboard Perseverance are, further conclusions regarding what is contained in the Wildcat Ridge sample will have to wait until it’s returned to Earth for in-depth study as part of the agency’s Mars Sample Return campaign. »
It’s perfectly reasonable to be curious, or even thrilled, about what NASA’s rover observed on Mars. Yet any announcement of life is a whole different ballgame. If such an announcement happens, potentially in the 2030s, it would be one of the most significant discoveries ever. Our view of the cosmos would be forever altered.
For now, there’s still only one place we know life exists. Treat it well.
