Scientists have found that meteor impacts are not random events but may occur as Earth passes through streams of meteoroids.
Meteor impacts are far less random than most scientists assumed, according to a new analysis of Earth-strike meteors.
The research, reported on the pre-press astrophysics website ArXiv.org
, concluded that meteor impacts are more likely to occur at certain times of the year when Earth's orbit takes us through streams of meteoroids.
The majority of meteors analysed hit the Earth in the second half of the year, say the researchers, brothers Carlos and Raúl de la Fuente Marcos of the Complutense University of Madrid
"This lack of randomness is induced by planetary perturbations, in particular Jupiter's, and suggests that some of the recent, most powerful Earth impacts may be associated with resonant groups of Near Earth Objects and/or very young meteoroid streams," they report.
Meteoroid streams can be generated by the break-up of an asteroid or comet.
A planet or moon can also affect nearby asteroids and meteors, herding them into loose orbits called 'resonant streams', which can be broken up by big planets such as Jupiter and Saturn.
The study is based on 33 meteor impact events detected between 2000 and 2013 by infrasound acoustic pressure sensors, operated by the Comprehensive Nuclear-Test-Ban Treaty Organization.
The sensors are designed to detect clandestine nuclear tests, but also pick up meteor impacts with an explosive energy in excess of a thousand tonnes of TNT.