On February 15, 2013 an asteroid about half the size of a football field will pass by the Earth with only 17,200 miles to spare. The asteroid, named 2012 DA14, will pass Earth closer than many man-made satellites. Don Yeomans of NASA’s Near Earth Object Program at JPL told reporters:
“This is a record-setting close approach. Since regular sky surveys began in the 1990s, we’ve never seen an object this big get so close to Earth.”
As it threads the gap “between low-Earth orbit, where the ISS and many Earth observation satellites are located, and the higher belt of geosynchronous satellites, which provide weather data and telecommunications”, NASA will use the opportunity to carefully study the flyby to glean data that could help them eliminate any future asteroid(s) that poses a threat to planet Earth.
“In 1908, something about the size of 2012 DA14 exploded in the atmosphere above Siberia, leveling hundreds of square miles of forest. Researchers are still studying the “Tunguska Event” for clues to the impacting object.”
During the hours around its closest approach, the asteroid will brighten until it resembles a star of 8th magnitude (not visible with the naked eye). Theoretically, that’s an easy target for backyard telescopes. The problem will be the speed of the asteroid. The asteroid will be racing across the sky, moving almost a full degree (or twice the width of a full Moon) every minute. That’s going to be hard to track with an amateur telescope.