Orbit of near-Earth asteroid Apophis showing the positions at its last approach on 14th December 2004. Apophis, or MN4, orbits the Sun every 323.5 days. Initial calculations showed that there was a chance that it would strike Earth on 13th April 2029. Subsequent studies have shown that it will miss Earth on this date, but only by around 36,000 kilometres, the same distance at which geostationary satellites orbit Earth. This approach may deflect it enough for it to collide with Earth on its 2036 approach. Apophis is 320 metres wide, too small for an impact to wipe out life on Earth, but it would devastate a wide area, releasing 65,000 times as much energy as the Hiroshima atom bomb.