As if we weren’t already living in semi-constant fear that a rogue comet could flatten a city or two, it turns out we’ve apparently been underestimating the likelihood of an impact with Earth. Yay?
A new report in Discovery cites a study by a team of astronomers who believe we’re not paying nearly enough attention to distant giant comets. At the moment, our planetary defense plan is to watch objects in the asteroid belt and the area between Mars and Jupiter. But research now indicates there are likely hundreds of giant 31-62-mile-wide comets (with much bigger orbits) rolling around out there just waiting to smash us. These are a bit harder to track, though, because they have unstable elliptical orbits that can take them all the way out to Neptune.
These massive balls of rock and ice zig and zag around Jupiter, Saturn, Uranus and Neptune, and the gravity from those planets can potentially shift these comets on a collision course with Earth. It only happens about every 40,000-100,000 years, but hey, it only takes one. If that were to happen, the comet would break up as it flew closer toward the sun, but it would create a prolonged period of bombardment that could cause a whole lot of trouble.
The report goes on to call these comets, dubbed “centaurs,” a “serious threat” that could potentially create a nuclear-winter-type event on Earth. The authors also urged the scientific community at large to focus more resources on understanding and tracking them in the future. You know, before one hits us.