The 1.2 mile-wide asteroid, officially named (52768) 1998 OR2, safely flew past our planet today 16 times farther than the Moon is. Despite being about 3.9 million miles (6.29 million km) at its closest, astronomers have dubbed the asteroid's trajectory a "close approach". US spaceagency NASAconsiders any asteroid to be close to Earth if it passes within 0.05 au of the planet - that is about five million miles (eight million km).