Sometimes asteroids come very close to home, about every six years. The latest asteroid to come closer to Earth than our own satellites appears today. Via Space.com:
An asteroid the size of a tour bus will fly past Earth today (June 27) so closely it will be beneath some of the planet’s satellites.
The rock, named asteroid 2011 MD will zoom by just 7,500 miles (12,000 km) above the planet, making a sharp turn forced by Earth’s gravity before winging off into space again. The flyby will occur at about 1 p.m. EDT (1700 GMT).
There is no risk of an impact, NASA scientists said. The space rock, estimated to be between 29 to 98 feet (9 to 30 meters) wide, is likely too small to survive a plunge through our atmosphere anyway. An asteroid this size, if it were mostly stony, would break apart and burn up before hitting the surface. Iron-heavy space rocks are better at surviving the fiery entry, however.
Either way, calculations show that asteroid 2011 MD will make a dogleg shift in its trajectory and scoot on by.
[Continues at Space.com]