In order to find out how long microbial spores can last in a dormant state and be able to revive, Charles Cockell, an astrobiologist at the University of Edinburgh, recently began one of the longest experiments in history .
Half a century in the future
To carry out the experiment, dried samples of Chroococcidiopsis and Bacillus subtilis bacteria were sealed in 800 glass vials , and then they were enclosed in two oak chests. Inside each oak box, the three vials are replicated at each time, one in a cardboard box and one in a lead-lined box to reduce background radiation derived from geological substrates.
From here, every two years for the first 24 years of the experiment, and then every 25 years for the next 475 years, one vial will be removed from each oak box and its contents examined to see if the spores can revive.
Thus, the last vial will be examined at a very distant future date, specifically in the year 2514. As David Farrier explains in his book Footprints :
The team had to write the instructions for their future colleagues, many of whom have yet to be born, with extreme care, in order to safeguard the experiment. For now, the instructions are stored alongside the samples, both written and on a USB memory stick.
This experiment tests the hypothesis that radiation from the planetary crust plays a role in molecular damage , leading to loss of cell viability over long periods of time.