Is there life on Mars? Was there life on Mars? We may have the answer to that very fundamental question within a few years, but regardless of what the answer is, we will need to have astronauts trained to understand how to search for life. Even if Mars turns out to be apparently lifeless, we still run the risk of contaminating organic material from Mars with our own microbes. Even on the Moon, where no life is expected, organic contamination of samples is still a concern – so astronauts need to know some astrobiology.
During early March, we were delighted to host ESA astronauts Mathias Maurer and Pedro Duque in our lab in Edinburgh to share with them some training and information on astrobiology. Our objectives over the two days were focused. First, we wanted to give them an insight into how life survives in extreme environments and makes a living in rocks. With this in mind we then transitioned into thinking about what signatures life leaves, from isotopic signatures in its chemistry to fossils of cells.
Knowing about the signatures and remains of life is essential if astronauts are to understand how their own activities could contaminate these samples. We then transitioned into a session in the lab, learning about how to make agar plates and the principles of aseptic techniques – the methods we use to keep contamination out of our samples. This session also taught them how easy it is to contaminate samples, but how this can be minimised.
Once we had learnt lab techniques, we discussed the principles of planetary protection and how concerns about contaminating samples would impact the way we go about collecting samples in the field and what the best sample-collection methods are.
To put all this into practice, we headed into the nearby hills called Arthur’s Seat the following day to learn about this ancient 350 million year old volcano. The astronauts learnt about geology and how to recognise the sorts of fractured rocks that might be habitats for life. Using rocks brought with us and on the ground, we practised field sampling using maximum aseptic collection techniques (the region is a park so no new samples were collected and rocks on the ground were returned to their original places).
Our training session lasted for two days, but in that time we transitioned from the basics of astrobiology to planetary protection and field implementation of the teaching. Throughout, our objective was not merely to teach astrobiology but to think about what an astronaut needs to know, whether they are on the Moon, Mars or any other planetary body. One outcome of the training session was to bring together a coherent two-day astrobiology training package for astronauts which we hope can be implemented in the future for any astronauts.