How big a deal is forward contamination of other planets?

Forward contamination, meaning infecting other parts of the Solar System with life from Earth – how big a deal is it? Science fiction has long featured cautionary tales of alien lifeforms infecting us. But what about the other way around? As we increasingly advance our presence off Earth, should we be doing more to stop organisms from our planet taking over others? We spoke to Scott Steele, a researcher at the Open University who studies this topic, to learn more.

How concerned should we be about forward contamination?

In 1967, space activities were limited due to money and capability constraints. Under its ninth article, the Outer Space Treaty (OST) introduced the concept of backwards contamination – the notion of extra-terrestrial organisms returning to Earth. This concept has featured prominently in science fiction stories in which catastrophic diseases from space wipe out humanity.

Forward contamination – meaning bringing organisms from Earth to other locations – unfortunately failed to feature in the OST or other subsequent instances of international space law. One interesting resource on this subject was a paper by Newman and Williamson that considered a limited approach to deal with forward contamination. Generally, though, there has been little concern about forward contamination. Today, scientific missions throughout our Solar System pay scant attention to their possible effects on potential extra-terrestrial life.

Star Trek’s prime directive is to observe and not interfere with other life forms – this is directly applicable to the issue of forward contamination, which is the interference with outer space and celestial bodies by the introduction of Earth microbes. The future of space activities means forward contamination is inevitable – the more humanity ventures to the stars, the more contamination becomes an issue. Science has identified some microbes that can survive clean rooms and solar radiation; they may be able to remain dormant in travel between celestial bodies. Once on a new surface, these microbes can adapt and alter the nature of scientific findings – they can produce false positives and contaminate areas of scientific importance.

Are current measures regarding forward contamination satisfactory, or should they be changed?

The Committee of Space Research (COSPAR) promotes at the international level a scientific approach to investigating celestial bodies. COSPAR guidelines indicate a rigorous process to limit contamination when investigating celestial bodies. These guidelines are widely accepted in the scientific community. However, international space law fails to consider them, leaving the guidelines merely as a “good practice”. This allows non-state actors to focus on profit and to follow the minimum requirements set forth by the state from which they are launching.

Whether COSPAR can be considered satisfactory or not is a moot point. From a legal view, without legal consequences, it cannot be enforced – there is no legal requirement for how to deal with crashing an object into Mars, for instance. One can see similarities in international environmental law – the Paris Agreement or the Kyoto Protocol, for instance, are unenforceable. We need stronger guidelines regarding forward contamination. This is especially so as non-state actors, not just government ones, play a larger part in exploring space. A robust ethical approach to forward contamination should guide future engagement with space.

The creation of space governance forum may be an ideal way to deal with this conundrum. Such a forum would allow science, technology, and law to collaborate and to hold community members to a certain level of accountability. COSPAR, UNCOPUOS, and regional space agencies could create such a forum. Moreover, such a forum could include environmental groups, insurance providers, and governments. The forum could perhaps be built on the basis of the UN Charter.

How did you become interested in forward contamination?

From an early age, I was fascinated by space. I “owned” a plot of land on the Moon (I now know that was a gimmick) and I avidly watched Star Wars and Star Trek. In 2018, I was introduced to space law at Sunderland University in a course taught by Professor Chris Newman (who is now at Northumbria University). Professor Newman covered many space issues, but I was particularly fascinated by space debris. I later received a master’s degree in international law from Newcastle University. With my increased understanding of international law, I decided to write my master’s thesis on removing debris without the need for consent. My research examined other areas of international law that were relevant to space debris removal.

Now I work and study at the Open University, under its AstrobiologyOU research group and its law school. A research grant of £6.7 million was awarded to AstrobiologyOU by Research England to focus on the research question of “Are we alone in the universe?” This allows me to further my work on COSPAR, planetary protection, forward contamination, and space governance. I am studying how COSPAR can be used to address forward contamination. I am researching how space governance relates to scientific investigation and legal certainty in space.