President Obama recently announced that he wants an American spacecraft to visit an asteroid by 2025. Experts say this goal will be extremely difficult to attain in 15 years because of the planning needed to rendezvous with an unscheduled asteroid. But Space.com reports that other experts say it is a mission that cannot be completed soon enough — the ability to nudge an a space rock from its path could help deflect future asteroids aimed at Planet Earth.
NASA is focusing its efforts on finding the right asteroid to knock off course. John Grunsfeld is an astrophysicist and a former NASA astronaut who flew on five shuttle missions. As he told Space.com, “by going to a near-Earth object, an asteroid, and perhaps even modifying its trajectory slightly, we would demonstrate a hallmark in human history … [It would be] the first time humans showed that we can make better decisions than the dinosaurs made 65 million years ago." He explained that if scientists don’t work on a solution to changing the path of an asteroid, life as we know it will certainly be ended by one.
According to Space.com, scientists estimate there are about 100,000 asteroids and comets near Earth and that 1,000 of them could be potentially dangerous. About a dozen of these asteroids could be reached by astronauts, but the target would have to be at least 300 feet wide to make it worth the trip. Even so, spacecrafts have landed on asteroids before. Japan's Hayabusa spacecraft just traveled to the asteroid called Itokawa, where it attempted to collected samples for scientists.
Obama’s asteroid mission is the first step in the ultimate goal of landing on Mars. This mission would be complicated. First, the flight to a space rock would likely take months. Then astronauts would have to be tethered to the asteroid to keep from floating away, as gravity forces would not be in effect. In addition, the space flyers would be outside the Earth’s protective magnetosphere and would be exposed to harsh radiation.
Nonetheless, some feel this is a risk we should take. TV's Bill Nye the Science Guy, vice president of the Planetary Society, told Space.com that "it's every bit as exciting in a different way, we're going to deep space. You turn around and take a picture of the Earth, and it's going to be a dot. You're not even going to see the atmosphere.” Sure, it’s risky and dangerous — but saving the planet could be a cool payoff.
For further reading: