Tardigrades on the Moon and space legal issues

Why is everyone in the space law community talking about tardigrades on the Moon? In April 2019, the lunar lander Beresheet – a privately funded Israeli project – crashed on the Moon. On board the spacecraft, Nova Spivack of the Arch Mission Foundation had decided to include some DNA in the payload, and, a few thousand extra dehydrated tardigrades had been attached to the “lunar library”. As for whether any of the DNA or tardigrades are still intact, that’s anyone’s guess, but Nova Spivack says there’s no reason to worry about water bears taking over the Moon. What about planetary protection and Article IX of the 1967 Outer Space Treaty?

What are Tardigrades?

Tardigrades, known colloquially as water bears or moss piglets, are a phylum of water-dwelling eight-legged segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them little water bears. In 1777, the Italian biologist Lazzaro Spallanzani named them “Tardigrada”, which means “slow steppers”.

They have been found everywhere, from mountaintops to the deep sea, and mud volcanoes, from tropical rain forests, to Antarctica. Tardigrades are among the most resilient animals known, with individual species able to survive extreme conditions – such as exposure to extreme temperatures, extreme pressures (both high and low), air deprivation, radiation, dehydration, and starvation – that would quickly kill most other known forms of life.

Tardigrades are usually about half a millimetre long when fully grown. They are short and plump, with four pairs of legs, each ending in claws (usually four to eight), or sucking disks. Tardigrades are prevalent in mosses and lichens, and feed on plant cells, algae, and small invertebrates. When collected, they may be viewed under a very low-power microscope, making them accessible to students and amateur scientists.

Tardigrades have survived exposure to outer space, a European Space Agency experiment has shown more than ten years ago. They are the first animals known to be able to survive the harsh combination of low pressure and intense radiation found in outer space. As to date, two species of dried-up tardigrades were launched from Kazakhstan in September 2007 aboard ESA’s Foton-M3 mission, which carried a variety of experimental payloads.

After ten days of exposure to outer space, the satellite returned to Earth. The tardigrades were retrieved and rehydrated to test how they reacted to the airless conditions in outer space, as well as ultraviolet radiation from the Sun, and charged particles from outer space called cosmic rays. The vacuum itself seemed to have little effect on the creatures. But ultraviolet radiation, which can damage cellular material and DNA, did take its toll.

In one of the two species tested, sixty-eight per cent of specimens that were shielded from higher-energy radiation from the Sun, were revived within thirty minutes of being rehydrated. Many of these tardigrades went on to lay eggs that successfully hatched. But only a handful of animals survived full exposure to the Sun’s UV light, which is more than one thousand times stronger in outer space than on the Earth’s surface. Before this experiment, only lichen and bacteria were known to be able to survive exposure to the combination of vacuum, and outer space radiation.

Tardigrades on the Moon

In August 2019, scientists reported that a capsule containing tardigrades in cryptobiotic state (all measurable metabolic processes stop, preventing reproduction, development, and repair) may have survived for a while on the Moon, after the April 2019 crash landing of Beresheet, a failed Israeli lunar lander.

It was just before midnight on April 11, 2019, and everyone at the Israel Aerospace Industries mission control centre in Yehud, Israel, had their eyes fixed on two large projector screens. On the left screen, was a stream of data being sent back to Earth by Beresheet, its lunar lander, which was about to become the first private spacecraft to land on the Moon. The right screen featured a crude animation of Beresheet firing its engines as it prepared for a soft landing in the Mare Serenitatis, or “Sea of Serenity”. But only seconds before the scheduled landing, the numbers on the left screen stopped. Mission control had lost contact with the spacecraft, and it crashed into the Moon shortly thereafter.

In the weeks following the Beresheet crash, Nova Spivack, the founder of the Arch Mission Foundation, a non-profit whose goal is to create “a backup of planet Earth”, pulled together the Arch Mission Foundation’s advisers in an attempt to determine whether the lunar library had survived the crash. Based on their analysis of the spacecraft’s trajectory, and the composition of the lunar library, Nova Spivack said he is quite confident that the library – a roughly DVD-sized object made of thin sheets of nickel – survived the crash mostly, or entirely intact. In fact, the decision to include DNA samples and tardigrades in the lunar library may have been key to its survival.

A few weeks before Nova Spivack had to deliver the lunar library to the Israelis, he had decided to include some DNA in the payload, and had added a thin layer of epoxy resin between each layer of nickel, a synthetic equivalent of the fossilised tree resin that preserves ancient insects. Into the resin had been tucked hair follicles, and blood samples from Nova Spivack and twenty-four others that had been said to represent a diverse genetic cross-section of human ancestry, in addition to some dehydrated tardigrades, and samples from major holy sites. A few thousand extra dehydrated tardigrades were sprinkled onto tape that was attached to the lunar library.

The promising thing about the tardigrades was that they could hypothetically be revived in the future. Tardigrades are known to enter dormant states in which all metabolic processes stop, and the water in their cells is replaced by a protein that effectively turns the cells into glass. Scientists have revived tardigrades that have spent up to ten years in this dehydrated state, although in some cases they may be able to survive much longer without water. Although the lunar library is designed to last for millions of years, scientists are just beginning to understand how tardigrades manage to survive in so many unforgiving environments. “It’s conceivable that as we learn more about tardigrades, we’ll discover ways to rehydrate them after much longer periods of dormancy”.

As a result, after the crash, “The payload may have been the only surviving thing from that mission” said Nova Spivack. In the best-case scenario, Beresheet ejected the Arch Mission Foundation’s lunar library during impact, and it lies in one piece somewhere near the crash site. But Nova Spivack says that even if the library broke into pieces, their analysis shows that these fragments would be large enough to retrieve most of the information in the first four layers. As for whether any of the DNA or tardigrades are still intact, that’s anyone’s guess, but Nova Spivack says there’s no reason to worry about water bears taking over the Moon. Any lunar tardigrades found by future humans will have to be brought back to Earth, or somewhere with an atmosphere, in order to rehydrate them. Whether this will be enough to bring them back to life, however, remains to be seen.

Space Legal Issues

Fortunately for Nova Spivack and the Arch Mission Foundation, spewing DNA and tardigrades across the Moon is totally legal. NASA’s Office of Planetary Protection classifies missions based on the likelihood that their targets are of interest to our understanding of life. As such, missions destined for places like Mars are subject to more stringent sterilisation processes than missions to the Moon, which has few of the necessary conditions for life, and isn’t at risk of contamination. In fact, Nova Spivack isn’t even the first to leave DNA on the Moon. This honour belongs to the Apollo astronauts, who left nearly one hundred bags of human faeces on the lunar surface, before they returned to Earth.

Let’s recall that the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies (entered into force on October 10, 1967), states in its Article I that “The exploration and use of outer space, including the Moon and other celestial bodies, shall be carried out for the benefit and in the interests of all countries, irrespective of their degree of economic or scientific development, and shall be the province of all mankind.

Outer space, including the Moon and other celestial bodies, shall be free for exploration and use by all States without discrimination of any kind, on a basis of equality and in accordance with international law, and there shall be free access to all areas of celestial bodies.

There shall be freedom of scientific investigation in outer space, including the Moon and other celestial bodies, and States shall facilitate and encourage international cooperation in such investigation”.

This article is very important since it establishes freedom of exploration and use of outer space, including the Moon. This means that states have the right to explore and use outer space, as well as the Moon and other celestial bodies. Since Beresheet was a private enterprise, some may argue that the Israelis had not the right to explore and use outer space. But Article VI of the aforementioned Outer Space Treaty notably stipulates that “States Parties to the Treaty shall bear international responsibility for national activities in outer space, including the Moon and other celestial bodies, whether such activities are carried on by governmental agencies or by non-governmental entities, and for assuring that national activities are carried out in conformity with the provisions set forth in the present Treaty. The activities of non-governmental entities in outer space, including the Moon and other celestial bodies, shall require authorization and continuing supervision by the appropriate State Party to the Treaty”.

As a result, Israel could have been held responsible for any damages caused by the Israel-based private company (let’s add to this the fact that the Launching State, as defined by the 1972 Convention, was also the United States of America, since Beresheet was launched from Cape Canaveral, in Florida). Did Beresheet, which could have brought life (contaminated?) to the Moon, break any law?

Article IX of the 1967 Outer Space Treaty notably declares that “States Parties to the Treaty shall pursue studies of outer space, including the Moon and other celestial bodies, and conduct exploration of them so as to avoid their harmful contamination and also adverse changes in the environment of the Earth resulting from the introduction of extraterrestrial matter and, where necessary, shall adopt appropriate measures for this purpose”. The important passage is “so as to avoid their harmful contamination”. Did Beresheet harmfully contaminated the Moon? When the Magna Carta of space law was negotiated, states feared that the Moon could become a place where the United States of America and the U.S.S.R. would fight. I once heard that states where concerned in the mid-1960s that the U.S.S.R. would contaminate the Moon, so that the U.S.A. would not go there (and possibly create military bases), with radioactive waste. It would hence be difficult to hold the Israelis responsible for having left tardigrades in cryptobiotic state on the Moon.

Article IX of the 1967 Outer Space Treaty continues and adds that “If a State Party to the Treaty has reason to believe that an activity or experiment planned by it or its nationals in outer space, including the Moon and other celestial bodies, would cause potentially harmful interference with activities of other States Parties in the peaceful exploration and use of outer space, including the Moon and other celestial bodies, it shall undertake appropriate international consultations before proceeding with any such activity or experiment. A State Party to the Treaty which has reason to believe that an activity or experiment planned by another State Party in outer space, including the Moon and other celestial bodies, would cause potentially harmful interference with activities in the peaceful exploration and use of outer space, including the Moon and other celestial bodies, may request consultation concerning the activity or experiment”. Did Israel believe that tardigrades in cryptobiotic state on the Moon “would cause potentially harmful interference with activities of other States Parties in the peaceful exploration and use of outer space, including the Moon and other celestial bodies”? We don’t believe so.

As a result, when talking about tardigrades on the Moon, we believe that neither did Beresheet (and therefore Nova Spivack and the Arch Mission Foundation), nor Israel (responsible under Article VI of the OST), broke the law.