The Mission V crew landed on sMars shortly after 4:30pm on January 19th. We started by unpacking our personal belongings in our rooms and getting settled into our quiet new home. Thanks to a day of healthy sun shining on our photovoltaics, we had full charge on the batteries when evening came. From our porthole window in the dining area, we could see the orange glow of our first Martian sunset above the ruddy hillside.
Once the sun sets on sMars, the temperature inside the habitat rapidly drops. Without much insulation or thermal mass, the habitat isn’t able to retain as much heat as a conventional house would. Stone and brick structures have excellent thermal mass and can stay warm even at low temperatures if the sun has been shining on it. Much like the kinematic inertia of a moving object might keep it in motion, a massive object can have thermal inertia making it resistant to changes in temperature. For example, a large rock in motion tends to stay in motion, and a large warm potato tends to be delicious.
Energy use is a balancing act. To conserve power for use overnight, we turned down the thermostat to about 60degF and bundled up in warm clothing for the evening. Luckily for the crew, the bacteria in the composting toilets prefer to stay above 55degF giving us an excuse to keep some heat on during the night.