During future space missions, humans may finally encounter extraterrestrial life forms, settling the age-old question of whether we are alone in the cosmos. But what if alien biology is so different from that of Earthlings that its presence could become a potential global hazard?
This is the concern raised by researchers Frederick I. Moxley and Anthony Ricciardi in a new study, which argues that in an era of sample return missions and space missions that are carrying humans and our robotic probes farther into the cosmos than ever before, we need to be prepared to enact measures to protect our planet against the unforeseen consequences of any potential alien encounters the future may hold.
“The advancement of space exploration into an era of sample return missions from Mars, asteroids, and icy moons raises the potential for biological contamination either to or from Earth,” the authors write in their recent study, published in the journal Ambio. Given the potential for such contamination, Moxley and Ricciardi approach the question of alien contact from the perspective of past examples where invasive species on Earth have caused major disturbances to the environments they encounter.
“We consider the possibility that extraterrestrial organisms introduced to Earth could behave analogously to invasive species by destabilizing ecosystems or interacting unpredictably with their new environment,” the authors write, pointing to the multitude of examples known to science, many of which involve the introduction of microbial organisms into new environments—often with devastating consequences.
In many cases, such organisms not only can survive in new environments, but can often adapt with remarkable speed, even in some of the most extreme environments.
This, the authors say, challenges the idea that extraterrestrial life might not even be capable of surviving on Earth, as expressed by some past research.
“The plausibility of encountering extraterrestrial life warrants stringent planetary protection measures grounded in biosafety and biosecurity principles,” the authors warn.
So how do they suggest protecting Earth against such potentially catastrophic events involving future encounters with extraterrestrials?
According to Moxley and Ricciardi, building a quarantine facility on the Moon could serve as Earth’s last line of defense against any unintended alien invasions that could radically disrupt Earth’s fragile ecosystems.
“Due to its proximity, natural isolation, and apparent lack of a biosphere, the Moon can serve as a secure site for biocontainment of extraterrestrial samples,” the authors write. In their study, they examine historical instances where biological invasions have led to catastrophic environmental changes and argue that constructing a biocontainment facility on the Moon “should form the cornerstone of modern astrobiological risk mitigation strategies.”
What the researchers propose falls in line with current plans NASA has for a permanent lunar base, which is one of the many ambitious efforts under its Artemis Mission. Such a lunar outpost, which will serve as the official Artemis Base Camp, is planned for construction near the Moon’s South Pole.
At a cost of close to $30 billion, the effort will help to facilitate an ongoing human presence on the Moon by as soon as 2028, according to current mission timelines, and will serve as a science hub in support of future lunar exploration.
For Moxley and Ricciardi, incorporating a quarantine facility within our future lunar infrastructure that can house any extraterrestrial life forms we may encounter could prove to be vital. Ultimately, having such a facility may play the important role of shielding Earth against unintentional contamination by a potentially invasive alien species.
The team’s recent paper, “Protecting earth from extraterrestrial contamination: The case for a lunar biocontainment facility,” was published in Ambio.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.