Elon Musk, and anyone else hoping to land a human foot on Mars, may have worked out the problems with rockets, with landing, and with how to keep a crew alive for the months-long journey. None of those things have gotten any easier. But it looks as if one obstacle that stood in the way of intrepid travelers everywhere may soon be removed. The rules meant to protect other planets from Earth-based contamination seem on their way to being relaxed. Or, in the terms of recent movies, it appears that space farmers will not be required to turn over their potatoes to U.S. customs.
A “planetary protection panel” put together by NASA has released a report calling many of the rules currently used to prevent the spread of Earth-germs to other planets “anachronistic.” That report suggests that there is little need to be concerned about contaminating the Solar System with earthly organisms, that concerns about not being able to tell our life from their life are overblown, and that if we’re seriously thinking of sending people to other worlds, we night want to set aside areas where people, and all their germs, are free to drop some DNA.
Going back to the 1950s, and perhaps inspired by a good dose of H.G. Well’s War of the Worlds denouement, scientists have insisted on a strict regime of treatment for both out-bound and in-bound craft visiting the Moon or other planets. That has included assembling probes in a sterile, clean-room environment, baking parts under bacteria-slaying heat, and in general trying to make sure everything going out there is deprived of any biological material from down here.
Those rules have also been pretty disdainful about the sterilizing effects of the trip through space itself despite all the radiation, wild temperature swings, and hard vacuum that implies. And there are reasons. Experiments going back to the 1960s demonstrated that a few bacteria, at least, could ride out the worst conditions for a period of months or years. But the new report echoes what some scientists have been saying for years—these efforts at sterilization can add enormously to the cost of probes meant for other worlds, but don’t really bring much value.
It’s not that scientists in the past didn’t have good reasons for such efforts. The Viking landers were cooked in purpose-built ovens to make sure they carried along nothing at all of Earth life, not so much because scientists worried about bringing an Earth-plague to Mars, but because sensitive experiments on the spacecraft meant to look for the presence of Martian life, might easily have generated a false positive if there were Earthly hitchhikers. But now that newer means of detecting life — and quickly sequencing it at the DNA level — are available, it’s possible to construct tests that look for life in ways that are can definitely exclude anything that is performing a 35 million mile photo bomb.
The result is a suggestion that NASA can ease off the efforts to assemble each probe as if it is heading into the world’s most stringent surgery. The surface of the Moon in particular can be considered as places where humans might want to look for signs of life’s origin in the early Solar System—so shouldn’t be scattering material willy-nilly—but has no native organisms to worry about. There is no lunar biome to worry about either contaminating, or being contaminated by.
Rather than treat all outbound probes, or potentially round-tripping humans, with the same strict rules for contamination, the report suggests that NASA establish “management zones” that seem to have an analog in wildlife preservation areas. “Astrobiology zones” could be established around areas that were thought to be critical to potential discovery of existing or extinct life. For example, such a zone might be established around areas of Mars that were thought to have flowing water in the past, or subsurface activity at present.
The second kind of zone established by the report would be zones for human activity. These zones would then be subject to all the bacteria that a human-infestation brings along, making probes and ships headed for these regions subject to much reduced efforts at sterilization.
This two zone system still offers potential for problems. Some of the most interesting places on both the Moon and Mars would be those where there is a high possibility for finding water ice. That ice can be used to create both air and rocket fuel as well as the water visiting humans would need. But icy areas might also be among those set aside for astrobiology, generating a resource conflict.
The report also suggests that NASA doesn’t have to be so strict about how it treats samples being returned from other planets to Earth. As with missions to those other worlds, some care would need to be taken that the samples didn’t get slathered by Earth-life and generate false-positives for discovery of non-terrestrial life, but there is little need to treat such samples as if they represent a potential threat.