1566 Icarus
Icarus makes a close approach to Earth at gaps of 9, 19, or 38 years. Sometimes, it comes as close as 6.4 Gm (16 lunar distances and 4 million miles), as it did on June 14, 1968. The last close approach was in 1996, at 15.1 Gm, about 40 times as far as the Moon. The most recent close approach was on June 16, 2015, 8.1 Gm (5 million miles).