The sixth closest asteroid encounter on record, the May 29 near-miss by the object catalogued as “2012 KT42”, was tracked by the NASA Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii as it whizzed inside the orbital distance of Earth geosynchronous satellites (6.6 Earth radii or an altitude of 22,000 miles). Credit: NASA, R.P. Binzel/MIT