We need to think about conservation efforts on Mars

Astrobiology is the scientific field that studies the origins, evolution, distribution and future of life in the Universe. In practice, this means sending robotic missions beyond Earth to analyze the atmospheres, surfaces and chemistry of alien worlds. Currently, all of our astrobiology missions focus on Mars, considered the most Earth-like environment beyond our planet. While several missions will be aimed at the outer solar system to study “ocean worlds” for evidence of life (Europa, Ganymede, Titan and Enceladus), our efforts to find life beyond Earth will remain primarily on Mars .

If and when these efforts succeed, it will have dramatic implications for future missions to Mars. Not only will great precautions need to be taken to protect Martian life from contamination by terrestrial organisms, but care must also be taken to prevent the same thing from happening to Earth (i.e. protection planetary). In a recent study, a team from the University of New South Wales (UNSW) in Sydney, Australia, recommends that legal or normative frameworks be adopted now to ensure that future missions do not threaten sites where Evidence of life (past or present) could be found.

The study was led by Clare Fletcher, a Ph.D. student at the Australian Center for Astrobiology (ACA) and the Earth Sciences and Sustainability Research Center at UNSW. She was joined by Professor Martin Van Kranendonk, ACA researcher and Director of the School of Earth and Planetary Sciences at Curtin University, and Professor Carol Oliver from the School of Biological Sciences, Earth and Environment at UNSW. Their research article, “Exogeoconservation of Mars,” appeared April 21 in Space policy.

The search for life on Mars dates back to the late 19th and early 20th centuries, when Percival Lowell made extensive observations from his observatory in Flagstaff, Arizona. Inspired by Schiaparelli’s illustrations of the Martian surface (which showed linear features he called “canali”), Lowell recorded what he also believed to be canals and spent many years searching for other clues of infrastructure and an advanced civilization. In the decades that followed, observatories around the world observed Mars closely, looking for signs of life and similarities to Earth.

However, it was not until the space age that the first robotic probes flew over Mars, collecting data directly from its atmosphere and taking close-up images of the surface. These revealed a planet with a thin atmosphere composed mainly of carbon dioxide and a frigid surface that did not appear hospitable to life. However, it was the Vikings 1 And 2 missions, which landed on Mars in 1976, which forever dispelled the myth of a Martian civilization. But as Fletcher told Universe Today via email, the possibility of existing life hasn’t been completely abandoned:

“I personally believe that it is unlikely that we will find evidence of existing (current) life on Mars, as opposed to evidence of past life on Mars. If we were to find existing life on Mars that could be proven to be endemic to Mars and uncontaminated by Earth, some believe it could be found underground in lava tubes, for example, and Others think that ice caps or any other possible source of liquid water might be a suitable location.

Ironically, these are the same missions that discredited the idea of ​​life on Mars and revealed evidence that water once flowed on its surface. Thanks to the numerous orbiter, lander and rover missions sent to Mars since the beginning of the century, scientists hypothesize that this period coincided with the Noachian era (around 4.1 to 3, 7 billion years). According to the most recent fossils, it was also at this time that life first appeared on Earth (in the form of single-celled bacteria).

Artist’s impression of Mars in the Noachian era. Credit: Ittiz/Wikipedia Commons

Our current astrobiology efforts on behalf of NASA and other space agencies focus on Mars for precisely this reason: to determine whether life arose on Mars billions of years ago and whether it co-evolved or not with life on Earth. This includes the proposed Mars Sample Return (MSR) mission which will retrieve drill samples obtained by the Perseverance rover from Jezero Crater and return them to Earth for analysis. Additionally, NASA and China plan to send crewed missions to Mars by 2040 and 2033 (respectively), including astrobiology studies.

These activities could threaten the very homes where evidence of past lives might be found or (worse) still exist. “Human activities could threaten sites like this, in part because of possible microbial contamination,” Fletcher said. “Evidence of life (past and existing) also has greater scientific value when within its paleoenvironmental context, such that any human activity that may damage the evidence of life and/or the surrounding environmental context presents a risk. It could be something harmless, like debris falling in the wrong place, or something more serious, like crossing potentially large outcrops with a rover.

Conservation measures must be developed and implemented before additional missions are sent to Mars. Considering humanity’s impact on Earth’s natural environment and our attempts to mitigate it through conservation efforts. In particular, there are many cases where scientific studies have been carried out without taking into account the heritage value of the site and where damage has been caused due to lack of appropriate measures. These lessons, Fletcher says, could inform future scientific efforts on Mars:

“It is important that we learn from what has been considered ‘damaging’ on Earth and take this into account when exploring Mars. If a site is damaged to the point that it cannot be studied in the future, then we are limiting what can actually be learned from a site. Considering that missions to Mars cost billions of dollars and must achieve specific scientific goals, limiting the information obtained from one site is incredibly detrimental. My recommendations are those of my article: interdisciplinary cooperation, drawing on experience and knowledge from Earth, creating standards and a code of practice (part of my doctoral work) and working towards creation of legislation on these issues. »

Artist’s rendering of NASA’s Dragonfly on the surface of Titan. Credit: NASA/Johns Hopkins APL/Steve Gribben

The need for exogeoconservation is essential at this stage. In addition to Mars, several astrobiology missions will travel to the outer solar system this decade to search for evidence of life on icy moons like Europa, Ganymede, Titan and Enceladus. This includes ESA’s JUpiter ICy moons Explorer (JUICE) mission, currently en route to Ganymede, and NASA’s Europa Clipper and Dragonfly missions which will launch for Europa and Titan in October 2024 and 2028 (respectively). Therefore, the ability to search for existing or past life forms without damaging one’s natural environment is an ethical and scientific necessity.

“I hope this article provides a starting point for everyone working in Mars science and exploration, as well as anyone thinking about space policy and exogeoconservation,” Fletcher said. “My goal was to begin to draw attention to these issues, and thus launch a generation of researchers and practitioners focused on the exogeoconservation of Mars.”

Further reading: Space policy