On June 27th 2011, a chunk of rock about the size of a school bus (though maybe as large as an 18-wheeler) whizzed by Earth at a distance of around 12,000 km (7,460 miles) from the ground. Discovered by LINEAR on June 22nd, it was designated 2011 MD by the MPC.
To put its close approach distance in perspective, consider a few facts:
- Earth’s diameter is 12,750 km (7,925 miles).
- GPS satellites orbit 20,200 km (12,555 miles) above the Earth’s surface.
- Geostationary satellites such as Meteosat orbit at a height of 35,800 km (22,250 miles).