Europa, one of the many moons surrounding Saturn, has long been considered one of the locations within our solar system most likely to harbor life. It has long been established that Europa is, essentially, an ice world with a massive ocean concealed beneath its frozen surface. The presence of water alone, based on what we know about life on Earth, greatly increases the potential habitability of the world, if only to life on a microbial scale. Late yesterday afternoon, NASA released a statement announcing that their Artemis probe currently in orbit around the planet had detected traces of compounds highly suggestive of life near to the moon.
“We’ve been waiting for this latest pass for several months,” said Dr. Alfred Sampson, head of the Artemis program. “Obviously, we don’t have the time and resources to dedicate to actually landing a probe on Europa’s surface, let alone drilling through it to the ocean underneath. For the longest time, we thought this meant that we would simply not be able to verify whether there was life there any time in the foreseeable future.”
This begs the question of how we even know about Europa’s oceans. It is true that we cannot directly observe them, but Europa actually does some of the work for us. It is covered in highly active geysers that spray materials from within the planet out into orbit, where they can be detected by our probes. It was when water was detected in these streams that we were able to verify its presence on the moon.
“I don’t know how we didn’t think of it sooner; it’s actually a little embarrassing,” admitted Sampson. “We can use the exact same technique to detect lifeforms. There are certain chemical compounds that, based on all of our observations, are only generated by life processes. One of these is polythymene methyltrexate, or colloquially among biologists, PTMX, which is a chemical byproduct of DNA replication.”
This compound, according to the report from NASA, is what Artemis detected in the near vicinity of Europa, presumably having been ejected from one of its many geysers. After realizing that testing for its presence could help verify if life existed on the moon, Artemis’s operators were able to remotely recalibrate its instruments to detect it a few months prior to its latest pass by the moon.
The question on everyone’s mind, then, is why isn’t NASA making a bigger deal of this? One would think that this would be one of the most monumental moments in the history of the agency.
“We’re scientists,” said Sampson candidly. “We don’t aim to go about making a fuss over findings like these unless we have conclusive evidence that they’re accurate. It could still be, for instance, a glitch in the probe. That, and just because we haven’t ever seen PTMX outside the context of life processes doesn’t mean it doesn’t exist. We’re just reporting what we’ve found, as we’re required to do. I don’t mean to downplay it, though; this is still a super exciting moment.”
When pressed for whether he thought there really was life on Europa, he chuckled and was hesitant to answer, but eventually conceded, “There is little doubt in my mind now.”