Not only did it make a very close approach to Earth yesterday, but astronomers got a better handle on 2014 RC’s size and how fast it spins during the flyby.
The space rock was originally thought to be 60-feet (20-m) across but we now know it’s closer to 40-feet (12-m) or about the size of a school bus and spinning very rapidly. Try one rotation every 15.8 seconds!
That makes 2014 RC the fastest rotating asteroid (by 50%) observed to date. Astronomers using NASA’s Infrared Telescope Facility (IRTF) on September 6 observed the space rock in infrared light to determine its composition. It reflects about much light (25%) as green grass and belongs to the “Sq class” of stony asteroids. Rocky asteroids are the most common kind. Based on its reflectivity, 2014 RC is much brighter than a typical comet and several other classes of asteroids.
In a story begging to be related but isn’t, a purported meteor crater showed up near Managua, Nicaragua’s international airport this weekend. Whatever caused it, the blast occurred during the early morning of September 6th, 13 hours before 2014 RC’s close flyby, which passed beneath Earth’s orbit anyway. A loud bang was heard and the ground shook, but there are no eyewitness reports or video of a meteor or meteorite fall. The crater is about 40 feet (12-m) across.
The surest way to confirm if a meteorite fell would be to look for fragments in and around the crater. No news yet on that. I’ll update when more information becomes available.