2005 HC4
2005 HC4 is the asteroid with the second-smallest perihelion and the asteroid with the smallest known perihelion of any known object orbiting the Sun from 2005 to 2024. Its extreme orbital eccentricity brings it to within 0.071 AU of the Sun and takes it as far as 3.562 AU from the Sun. Since then, another asteroid,, has been found to have a closer perihelion, at about 0.070 AU. Due to its very small perihelion and comparably large aphelion, achieves the fastest speed of any known asteroid bound to the Solar System with a velocity of 157 km/s at perihelion.