If you’ve ever had a nightmare about an asteroid or other large extraterrestrial object crashing into the Earth, you probably imagined it hitting solid ground. That could very well happen, but considering how much of our planet is covered by oceans, you’d be better off planning for an aquatic impact instead. Researchers at the Los Alamos National Laboratory cooked up a visualization of just such a scenario, and it’s equal parts reassuring and horrifying.
For starters, if the asteroid were to strike the ocean within about 12 miles of a coastline, it would likely wipe out a good chunk of whatever happens to be residing on the nearby land. That would be a pretty big bummer, but the good news is that if the rock hit the water way out in the middle, we don’t actually have to fear a giant mega-tsunami like you might imagine.
Using the ridiculously powerful computers and software at their disposal, the scientists simulated the potential consequences of a variety of asteroids striking the ocean, as well as whether or not the rock exploded above sea level before impact. What they found was that the way the asteroid’s kinetic energy is transferred to the water can vary greatly depending on conditions, but a tsunami created by such an impact isn’t likely to obliterate the coastlines the way a much closer impact would.
That’s good news, but there’s still some pretty serious consequences to a mid-ocean asteroid splash, namely the vaporization of the water being struck. If the asteroid is steaming hot, it has the potential to send hundreds of megatons of water into the atmosphere. That may not sound like a big deal, but if the water vapor reaches the stratosphere, it can stay there for years. Such an even would produce a greenhouse effect that could dramatically alter the climate.
In short, there’s really no “good” scenario when it comes to an asteroid hitting the Earth, but if one ever does swing by and make a splash, just cross your fingers that it’s small.