One of the goals of our visit to 395A was to deploy an experimental logging tool known as the Dark Energy Biosphere Investigative Tool, or DEBI-T, for short. Logging tools are instruments designed to scan a borehole, after it has been drilled, to gain a better understanding of the characteristics of that hole. These instruments are lowered through the drill pipe and into the hole to measure characteristics such as density, porosity and conductivity. The logging in 395A was different in two respects: first, 395A was already drilled, and second, the instrument suite included DEBI-T, an instrument we designed to assess how many bacteria might be within the borehole.

We began logging operations early Saturday morning. We managed to get about 60 meters into the hole before hitting an obstruction that we could not get past. After several attempts, we came back up so that the drillers could use a bit at the bottom of the pipe to push through the obstruction. Afterwards, we were able to go back through the pipe and into 395A to start logging. We finished logging early Sunday morning, a little over 24 hours after we started! Needless to say, we are all tired, but in good spirits because DEBI-T performed well. We’re currently studying all the data to find out how many microbes are living down there.