We're going to put someone on an asteroid by 2025. Crazy. But the gravity on asteroids is so weak that we won't stick to it. NASA plans to harpoon an asteroid like a giant space-whale. Now that's my kinda crazy!
Today NASA announced an updated survey of near-earth asteroids. It's good to know what's out the that might, y'know, crush us, but also it's good for picking a likely asteroid to land on, which is something NASA will be working on for the next decade and a half. Once the spacecraft gets near it, there's not nearly enough gravity to pull us in or keep us there. So we're going to shoot it, with some sort of harpoonish grappling thingie, and use that tether to pull us there. Peep the video.
What they shoot it with will depend on what the asteroid is composed of:
"Some asteroids might have a metallic core, and trying to anchor to them would be like banging a nail into an anvil," says Jeffrey Hoffman, a professor of aeronautics and astronautics at MIT and a former astronaut. "Others may just be a rubble pile, which would be like trying to pitch a tent on a snowfield."
There's even some talk of lassoing one by wrapping a cable all the way around it. Sorry NASA, I'm going to veto that. Any asteroid that is small enough to lasso is not cool enough to visit. We need to think bigger! What happened to Mars? We're not going to inspire a generation of children to do their homework by visiting a lil' space rock. Let's get planetary here, people. [Popular Mechanics]