Earth rises above the lunar horizon in an image captured during the Apollo 11 mission, July 1969 (NASA)

‘Planetary protection’ rules are making it difficult to explore space.

On April 11, 2019, the Israeli SpaceIL company’s Beresheet (Hebrew for “In the Beginning”) lunar lander crashed on the Moon. Beresheet’s payload, supplied by the non-profit Arch Mission Foundation, was meant to be an informational backup for the Earth. It included a DVD containing 30 million pages of human knowledge, as well as 60,000 etched pages requiring no computer to read, keys to 5,000 languages, and DNA samples from 25 people. According to Arch Mission Foundation chairman Nova Spivack, in case of catastrophe, this informational library, parked on the Moon, could be sufficient to “regenerate the human race.”


Many might consider Arch’s mission fanciful, others profound. But few objected. After all, it was their money. Creative people have certainly done sillier things. Too bad about the crash, though.

But then it came out August 7 that Beresheet was carrying an additional cargo, some 10,000 microscopic animals called tardigrades, on a postage-stamp-sized piece of tape. Known to amateur microscopists as “water bears” or “moss piglets,” these animals have the capacity to survive dehydrated in a dormant state for years, and to be highly resistant to radiation damage as well. Now they were on the Moon.

At first reporters reported the story with a light touch. “Thousands of tardigrades stranded on the Moon after lander crash,” Mindy Weisberger playfully wrote in LiveScience. “Water bears stuck on the moon after crash,” reported the BBC. “There’s definitely some great source material for a sci-fi horror movie. Attack of the Moss Piglets from the Moon? We’d watch it.”

But alas, the fun didn’t last. “Tardigrades on the moon is not good,” proclaimed NASA Goddard-based astrobiologist Monica Vidaurri in a series of tweets August 10. She continued (breaks between tweets omitted):

It is not cute. It is the result of a major gap in accountability for planetary protection and ethics between public and private science, and we have no idea what can happen as a result. It means that the private sector can keep doing as it wishes. It means they don’t answer to any protections/ethics office. And the fact that nothing is happening in terms of policy, and that decontamination standards STILL have not been updated, is dangerous beyond imagination. And if you are thinking anything along the lines of ‘sweet, we made moon beings!’ Then stop. Think carefully. WE made something on ANOTHER world that we do not fully understand. It has an environment, even if we deemed it ‘barren’ to any life on earth . . . What you are doing is showing excitement at the long history of forcing OUR values, systems, and in this case, living beings on another world. That is not our right, and it is not our job. If we carry on with that mentality, even if we took away the ‘colonization’ word the premise is the same. It’s colonialism. It’s imperialism.

J’Accuse!


Other putative planetary protectionists affected a greater degree of sobriety, but nevertheless joined in the inquisition, with claims that the offenses committed in L’Affaire Tardigrade threatened not only lunar science, astrobiology, and paleontology, but the entire structure of international law.


These claims are of significant clinical interest, so let’s take a moment to examine them.

At the core of the planetary protectionist prosecution’s case is the claim that delivering a milligram of dormant tardigrades to the Moon constituted “harmful contamination” of another world, which is forbidden by the Outer Space Treaty of 1967. But this is nonsense, because while it is conceivable that the tardigrades might have survived the crash, and even remain revivable for several years on the Moon in dormant dehydrated form, they cannot metabolize there, as there is no liquid water on the lunar surface. So until and unless someone goes there and collects them and takes them into a lab for scientific study, they are just so much dust.

Moreover, the Beresheet mission was hardly the first time anyone delivered microorganisms to the Moon. In fact, the Apollo missions left not milligrams, but kilograms of live microbes on the Moon in bags of human feces. This was an intelligent thing to do, since by leaving wastes behind the astronauts were able to return with more Moon rocks, which, pound for pound, are worth a lot more on Earth than manure. But it wouldn’t matter if they hadn’t, because as soon as the astronauts opened the door of the Lunar Module, millions of microbes were released on to the lunar surface, millions more hitched rides outside on spacesuits, and billions more were sent back down after the Lunar Modules left behind in orbit eventually crashed onto the Moon. Furthermore, even if, at great expense, those releases could have been prevented by engineered solutions, it still would have been impossible to conduct the Apollo missions within planetary-protection guidelines since it could never have been guaranteed that the Lunar Module would not crash, an event that would have released microbes all over the landscape.



Monica Grady, a leading astrobiologist with the U.K.’s Open University at Milton Keynes, acknowledged this history, but commented, “You might say [planetary protection] was broken in 1969 when Neil Armstrong and Buzz Aldrin were there, which is true, but since then we’ve become much more aware of how we should preserve these planetary bodies.


“I don’t think anybody would have got permission to distribute dehydrated tardigrades over the surface of the moon. So it’s not a good thing.”

More aware, or less aware? The Apollo wastes were dehydrated and effectively sterilized by the lunar environment within hours of being left behind, and the missions would have been impossible without accepting such transient releases. So something is “not a good thing,” but it’s not that tardigrades were sent to the Moon. It’s that nobody “would have got permission” to do it.

If you can’t send tardigrades to the Moon, you can’t send people to the Moon.

Moreover, there are some deeper problems here. In the first place, who gave the Moon to astrobiologists? Giving the Moon to astrobiologists is like giving the stratosphere to ichthyologists.

But what about Mars? In contrast to the Moon, the Red Planet is indeed of significant justifiable interest to astrobiology. While the lunar-surface combination of daytime temperatures of 127 degrees Celsius (260 Fahrenheit) and hard vacuum would qualify it as an excellent lab autoclave, completely precluding any viable microbial life, on Mars there are no such forbidding conditions. Moreover, unlike the cold, dry, very thin-aired conditions prevailing there currently, the early Mars was warm and wet, with a thick CO2 atmosphere, making it a near twin for the Earth at the time when life first appeared here. So life could have developed on Mars, and even if it can no longer survive on the surface, it might have left behind fossils, and even still persist in underground hydrothermally warmed reservoirs. So wouldn’t science be served by banning humans from Mars?

No. Fossil hunting on Earth requires hiking long distances through unimproved terrain, doing heavy work with pickaxes, and performing delicate work peeling off layers of sedimentary rocks to reveal the remains of life trapped within. Finding and characterizing extant life on Mars will require setting up drilling rigs to probe hundreds of meters into the ground and bring up water samples, and then subjecting them to biological surveys and biochemical testing in a lab. All of these operations are light years beyond the capability of robotic rovers. As for the objection that if we send humans to Mars we won’t know if the life we find there is native or something we brought ourselves, it is nonsense. If it is native life, it will have left fossils or other biomarkers to prove its existence on Mars before our arrival. That’s how we know there was life on Earth prior to the appearance of humans here. To believe otherwise is to concur with the creationists who argue that fossils do not prove the existence of life on Earth prior to humans because God could have created the planet with fossils included. That is not science.


We don’t have to wait for human missions to become feasible for planetary protectionism to damage Mars exploration, it is doing so already. In 2015 the Curiosity rover, sent to Mars at a cost to U.S. taxpayers of over $2 billion, was blocked by planetary-protection considerations from investigating nearby places where it appeared that subsurface water was seeping to the surface. These might conceivably have contained microbes or remains of microbes. NASA’s planned Mars sample return mission has been enormously complexified, with multiple in-space autonomous rendezvous and dock operations inserted into the mission plan, in order to meet planetary-protection demands. These include not only “protecting” the surface of Mars from (impossible) contamination by microbes transported from Earth, but protecting Earth from (impossible) microbes living on the Martian surface (which if they did exist, would have long since arrived here on their own riding many of the 500 kg of naturally ejected Mars rocks that arrive here every year.) As a result, the sample return has been turned from a mission into a vision. In fact, owing to the burdens imposed on mission design by planetary-protection requirements, NASA has not sent a life-detection experiment to Mars since 1976.

So here we are, spending billions on a robotic planetary-exploration program and tens of billions on a human-spaceflight program while submitting those programs to planetary-protection restraints that preclude them from accomplishing their goals — restraints whose absurd foundations are laid bare by the willingness of their advocates to fanatically demand their enforcement even for a self-sterilizing environment such as the Earth’s Moon.


But there is a bigger question. It’s not just a matter of who gave the Moon to astrobiologists, but also of who gave the universe to professional scientists. Humans do not exist to serve scientific research. Scientific research exists to serve humanity. We learned a lot of science by settling America, but that’s not why we did it. We will acquire vast new knowledge by becoming a spacefaring species, but that is not why we should do it. We should do it to establish new branches of human civilization, which will enrich the human story in the future as much as human colonization of the Earth has enormously enriched it compared with what it would have been had we remained in our original homeland in the Kenyan Rift Valley. We will create new nations, sporting new languages, literatures, inventions, traditions, and heroes, on new worlds filled with wonders to be discover, certainly, but also history waiting to be made.

Our presence will not “contaminate” these worlds, but enrich them fabulously. Settling them is not “imperialism,” it is construction. Humans are not vermin. We are creators, not destroyers. A living world is better than a dead world. A world of thinking beings is better than a world bereft of them. We are not the enemies of life and thought, we are their vanguard. It is our place to continue the work of creation. If we can, we should not just bring life to Mars, but bring Mars to life.

I think we will. And when we have, no one will be able to look on our work and not feel prouder to be human.