This Friday, a small asteroid will pass quite close to Earth. 2012 DA14 is a 60 meter ('Olympic pool size') asteroid that will pass between the low-Earth orbit satellites and geostationary satellites, at a distance of about 17,000 miles, a close shave by astronomical terms, but not something that is posing any kind of threat to the planet.
Asteroids pass near to Earth all the time, and the largest of them are being closely tracked. At this time over 1300 potentially hazardous asteroids (PHAs) are being watched, but none of them are on a collision course with Earth. For the foreseeable future, we have nothing to worry about - - at least as far as asteroids go!
If you want to watch the fly-by, you can check out a number of websites that will have live video feeds of the asteroid. At closest approach, it will be daytime in California and not visible, but the video feeds will be delivered from the other side of the planet. It won't be overly dramatic -- just a spec of light moving against the backdrop of stars. As one website put it, the size and distance of 2012 DA14 will be, on the scale of a 12-inch globe of the Earth, a grain of sand 2 feet away from the surface of the Earth. That's a good reference.