01/19/2015
Andrew Henry
Journalist Report 10
Another sunny but cooler day on Mars. After our rest day yesterday, we resumed our normal routine, rising at 7 and prepping for an EVA. Today’s EVA was another quadcopter flight close to the Hab to test out the repairs made after the previous incident. The team then took the ATVs out to do some scouting for future quadcopter flights.
Those who stayed behind took part in some exercise. Exercise is becoming an increasingly regular activity here, as it’s a great way to burn off some excess energy and boost your mood -- whether by indulging in calming yoga or having an overly fit trainer yelling via video. Here at MDRS we have full Earth gravity, but on real space missions, exercise is vital in keeping the body conditioned due to the lack of gravity. Humans evolved in the presence of Earth gravity, and we rely on it to keep healthy. Even those of us who lead a sedentary lifestyle are almost constantly doing some sort of mechanical work to counteract the effects of gravity. In a microgravity environment like that experienced by astronauts on the International Space Station, muscle and bone mass is lost because the body does not need to do any work against gravity.
Astronauts compensate for the lack of gravity by doing daily exercise for up to 2.5 hours every day, but this is only partially effective. Moreover, exercising in microgravity is a challenge, and it requires special equipment to be developed. If you think about it, your typical gym weights will be fairly ineffective in the absence of gravity. Although they will have some inertia, they will have no weight, so they don’t make for great exercise. Likewise, pushing or pulling on anything will result in the astronaut being pushed in the opposite direction. This happens on Earth as well (Newton’s Third Law!), but gravity stops us from floating away.
Some exercise equipment still works in space though, and treadmills have been a staple of space missions since the 70’s. In order to use a treadmill in space however, the astronaut needs to be strapped down with bungee cords. For load-bearing exercises, springs and pistons can be used in place of weights, as is the case with NASA’s Advanced Resistive Exercise Device.
The gravity on Mars is about 1/3 of the Earth’s, so astronauts will not experience as much bone and muscle degradation as they do in space. Scientists do not yet know however what the long term effects of this reduced gravity will be on astronauts, but whether it’s for physical or mental health, exercise will be part of their daily routine.
Tomorrow we will take the ATVs out for another EVA. Tomorrow’s EVA will have three objectives. The first is to do some field testing of the EVA assistant software (the arm-mounted smartphone component of the EVA planning tool), and secondly to map some more of the roads around the hab. We have been tracing our GPS location while navigating some of the roads as it’s an easy way to collect important contextual data for the EVA Planning tool. Finally, the quadcopter will take another flight tomorrow in order to collect some imagery to be used for assessing the method developed for determining the safety of a target terrain area.