Asteroid impacts are rare, but they can cause incredible harm (look what one did to the dinosaurs!). In 1908, one of them flattened 800 square miles in the Russian countryside. What would have happened if it had hit a major Western city instead?
We can use robots to mine them, but we don't want them to impact us, so in 1992, Congress asked NASA to begin looking for asteroids whose orbits might make them a threat to the Earth. At the moment, NASA is aware of 1,320 “"potentially hazardous asteroids" that are large enough to cause us problems. But even relatively small impacts can do a lot of damage, depending on their speed and where they hit.
In 1994, astronomers watched through telescopes as the fragments of the comet Shoemaker-Levy 9 smashed into Jupiter. The energy released by this collision was hundreds of times greater than the combined explosive power of every nuclear weapon on Earth. The Earth-sized dent in the Jovian atmosphere persisted for months.
On June 17th 2002, astronomers spotted an large rock that came dangerously close to us, passing inside the orbit of the Moon. The problem was, they only noticed this three days AFTER its point of closest approach.
In order to keep us safe, NASA is planning to launch a space telescope called NEOCam (Near Earth Object Camera), which is designed to look for space rocks. And a private charity is funding the launch of another asteroid-spotting telescope called the Sentinel, which will be sent into space by the private Space X company in 2018, which is taking over many of the projects that taxpayer-funded NASA used to do.
While NASA is busy looking for asteroids, OUR readers are busy looking for UFOs and aliens--and WE'VE found them! We post UFO sightings regularly in our "Out There" crawl and in order to find out what the Visitors are up to, we interview contactees regularly (NOTE: Subscribers can still listen to this show), so if you want to know what's REALLY going on, be sure to subscribe today!