Wednesday, 21 November 2012

lost in space

On Tuesday we went to Brock University with our dad, and listened to his class. The lesson was all about microgravity. Microgravity is the lack of gravity in space. Dad was talking about how in microgravity, you grow a little, because the disks in you vertebrae expand, and your muscles are not being pulled down by gravity. It is the same when you are lying down in bed, gravity is not pushing down on your head and shoulders, so the disks in your vertebrae can expand, and your muscles are not pulled down. but during the day, because you are standing up, the disks are flattened again, and your muscles are pulled down.

Also in space all of your muscles grow weaker because you do not need to use them to stand, and to move around you only need a small pull or push with your arms or legs to get you moving. To study this scientists do bed rest studies, where subjects have to just stay in bed for long periods of time, like 6 weeks. In space your bones get weaker, also you heart, and pretty much all of your muscles get weaker from you not having to use them.

Some things astronauts use to stay strong are treadmills and stationary bikes, and they also use bungee cords, which they attach to part of the  shuttle. The treadmills and bikes, have to 1. be very light, because every kilogram of weight is very expensive to send up to space, and 2. be as simple as possible, since motors might interfere with the motors and navigation of the shuttle. The treadmills are more just a slippery surface, and the astronauts just slide on it in the socks, they also are attached to it by bungee cords, so they do not fly away. The bikes are similar with a very simple design that works and you are just attached to it by some bungee cords.