The Gentle Pull of Reality

Research on space missions that require astronauts to endure weightlessness for extended periods of time is giving us an interesting picture of how our bodies cope (or don’t) with low or no gravity. The bones of astronauts tend to become less dense because they don’t need to support nearly as much weight/force as they do on Earth. The muscles lose mass for the same reason. And not just the muscles that get us out of our chairs, but heart muscle mass, too: the blood in our body is easier to pump when there’s no downward pull to fight. Humans just seem to deteriorate in a weightless, effortless, floaty environment. The research is important for helping us develop ways of keeping the astronauts healthy during these long missions in Earth orbit, or for another Moon mission or maybe even to Mars.

The effects of weightlessness can be mitigated somewhat by using some special exercise devices, but for really long trips a constant, gentle pull of artificial gravity is probably needed to keep the body functioning properly. Don’t want our brave men and women to come back from Mars looking and moving like rubber chickens...

And if you look at the research from a slightly different angle, it gives us clues about how to stay healthy during our everyday, normal mission of living on Earth. Gravity and effort don’t hold me down or hold me back—they quite literally hold me together.