The Yarkovsky effect is the lob-sided emission of radiation from a rotating object orbiting the Sun, due to uneven heating. It is named after the Russian engineer I. O. Yarkovsky, who first proposed the idea around 1900. Among other things, it has been used to explain why Earth is hit surprisingly often by meteorites. The uneven heating of a small rock in the asteroid belt by the Sun, which makes the day side warmer than the night side, creates a small force – enough to deflect the object into one of the resonance zones where the combined effect of Jupiter and Saturn's gravity pulls kick objects into the inner solar system. Combined with other, less subtle methods for getting fragments Earth-bound, including asteroid impacts, the newly-proved method appears to account for the total yearly shower of space rocks.