1566 Icarus

Orbit of Icarus

Orbit of Icarus and position on 1 January 2009.

1566 Icarus is a member of the Apollo group of asteroids, discovered by Walter Baade in 1949. Its orbit carries it well within the orbit of Mercury, but not quite as close to the Sun as 2000 BD19 (0.09 astronomical units), 1995 CR (0.12 AU), or 3200 Phaethon (0.14 AU). It was the first Mercury-crosser to be found.


Icarus ranks fifth on the list of potentially hazardous objects, though it will not come within several million kilometers of Earth in the foreseeable future. During its last "near miss," on 14 June 1968, it approached us to within 6.5 million kilometers – never a threat, but enough to have one cult retreating to a peak in Colorado to escape the anticipated slide of California into the Pacific.


diameter 1.4 km
spectral class U
rotational period 2.27 hours
semimajor axis 1.078 AU
perihelion 0.19 AU
aphelion 1.97 AU
eccentricity 0.827
inclination 22.9°
period 1.12 years