Articles tagged with "orbit"

Are we going to get trapped on earth by a swarm of colliding space debris?

For almost half a century, it's seemed like human destiny to go into Space. When we were kids, everyone wanted to be an astronaut when they grew up. The loss of the Columbia space shuttle hasn't extinguished that dream, but it firmly reminds us that leaving the Earth behind is a very difficult thing to do. If things were just a little bit different - if our species were as big as elephants, or aquatic, or if the Earth's gravity were much stronger, it may have been impossible. As it is, raising a human being into low Earth orbit, to say nothing of going further, is a hugely expensive proposition. And once up there, the lack of gravity leads to muscle wasting and other physiological problems. Food and air also need to be brought up from the planet below.