An asteroid about the size of a school bus will be closest to earth today, September 24, NASA confirmed. The asteroid, about 15 to 30 feet wide, is thought to be a small near Earth Asteroid that will pass through the earth about 13000 miles from the earth's surface.That's enough to get the asteroid close to the orbit of a geostationary satellite about 22000 miles from earth.
Based on the brightness of the asteroid, scientists estimate the size of the asteroid, known as 2020 SW, at 15 to 30 feet. Although an asteroid the size of a school bus looks large, if it enters the earth's atmosphere, it will almost certainly disintegrate in the upper atmosphere and become a bright meteor like a fireball.
After approaching the earth, the asteroid will continue to orbit the sun until 2041. That year, the asteroid will make a more distant flyover of the earth. Although the asteroid is not a threat to the earth, NASA received a mission from Congress in 2005 to try to find at least 90% of the near Earth Asteroids larger than 460 feet in length or larger.
It's very difficult to find asteroids the size of 2020 SW, unless they're very close to earth. NASA is improving its detection capabilities and says it expects to find asteroids of the size at least a few days before they approach earth.