There are no two ways about it; a large enough asteroid strike would be bad news for life on
Earth. Were a massive rock from space to crash down anywhere on our planet, then we’re talking an
all-out global catastrophe. But still, what would unfold if the fates truly aligned against us,
and that same rock happened to land on another major doomsday target? This is WatchMojo,
and today we’re answering the extraordinary question; what if an asteroid hit Yellowstone?
Yellowstone National Park surely delivers some of America’s most picturesque and breath-taking
landscapes… but, beneath all that beauty, there’s some serious trouble brewing. Much
of the park doubles up as the Yellowstone Caldera, the most famous supervolcano on
the planet. We took a deep dive into the precise mechanics of Yellowstone in another recent video
– so be sure to check that out after this – but, for now, here’s a brief rundown. Beginning about
five miles below the surface of the park there sits a massive, fifty-mile-wide, ten-mile-deep
magma chamber. Burning, toxic, molten material is always churning away here, and the pressure is
continually cranking up. One day, that pressure will tell, and Yellowstone will blow… in what
could go down as a defining and catastrophic moment in not just the history of humankind,
but the history of Earth itself. In recent times, there’s been plenty of talk over exactly
how concerned we should be. We know of at least three major eruptions in Yellowstone’s relatively
recent history; one that was 2.1 million years ago, another that was 1.3 million years ago, and
another that was around 640,000 years ago. Crunch those numbers, and it can be argued that we’re
due another eruption any day now. But, really, almost all scientific predictions claim that
we’re actually almost certainly safe, and probably will remain safe for thousands of years more. So,
there’s no need to overly worry, just yet. But, still, what would happen if the natural course
of Yellowstone was ever influenced by an external factor? Even if it doesn’t blow of its own accord,
might something else trigger the disaster anyway? What would happen if an asteroid landed right on
top of it? We’re talking about the ultimate in doomsday scenarios here – an asteroid strike
and a super eruption, all at once. One moment the Earth’s as it is right now, the next it’s
changed forever. And there’s no doubt that such an event would cause untold destruction.
An asteroid the size of what’s probably the most famous asteroid in Earth’s history (the
one that’s widely believed to have killed off the dinosaurs) would almost certainly be enough
to at least disrupt the Yellowstone Caldera into some kind of action. We know that the dramatic,
physical effects of the Chicxulub impactor – the dinosaur asteroid – can still be traced in the
landscapes and formations across the Yucatán Peninsula, in Mexico, where it struck around
sixty-six million years ago. It’s thought that that rock had been a little over six miles wide,
but of course there are many larger asteroids than that out there, too, tumbling through
space. That event was already enough to trigger widespread extinction… but really, then, it still
(unbelievably) could’ve been worse. The asteroid might’ve been even bigger, and the impact – which
it’s thought already generated the energy equivalent to many billions’ worth of atomic
bombs – might’ve been even more devastating. Clearly, with or without a supervolcano,
we know that another asteroid of that size could bring about Armageddon all on its own. Equally,
with or without an asteroid, a Yellowstone eruption could also trigger the end of days,
all by itself. Creating (as it would) a miles-high plume of toxic, volcanic debris,
and sending a rushing, crushing, deadly fog of ash and rock across all North America… when
Yellowstone blows, if it does so to its highest potential, we could be facing a worldwide climate
disintegration. Thick, smoky clouds even as far as Europe and beyond, choking the air and perhaps
even blocking out the sun – according to some of the harshest “worst case scenario” predictions.
The water cycle is ruined as it becomes saturated with burning ash; scorching periods of blistering
rain further harm the humans that are left, while also destroying the crops that remain;
and a global shutdown of power and communications makes mounting a recovery even more difficult. So,
all in all, if you happened to be alive on the day that an asteroid strikes Earth and it falls
on (or close to) Yellowstone, to cause it to blow… your chances of survival in the short
or long term are extremely slim. However, while there’s no real-world data to show exactly how
this scenario would unfold, one possibility is still that an asteroid might hit Yellowstone and
not trigger a separate eruption. When it comes to Earth’s deepest geological, tectonic, and
volcanic processes, they’re notoriously difficult to predict. In the case of Yellowstone, observers
have a few key features to watch out for that might indicate a coming eruption – including an
increase in local seismic activity, and the ground literally rising and falling as if the park itself
is breathing. But, if an asteroid were to land on top of that – like, right on top of it – then the
impact itself might just as well cancel out the super eruption. The volcano could well still blow,
but it would be as though it had been swallowed up by the also apocalyptic effects of the initial
asteroid strike. That is, if the asteroid is big enough… and, really, any asteroid that brings with
it enough power to set off Yellowstone would have to be very, very big. Perhaps the true worst-case
scenario here, then, is that an asteroid might strike somewhere else on Earth, but directly
provoke Yellowstone into an eruption, as well. We know that following previous asteroid events in
Earth’s history – including the Chicxulub asteroid that ended the dinosaurs – there have been
volcanoes blowing their tops all over the world map as a follow-on result. Ultimately, a large
asteroid event is one of the only things that can have an instant impact even on the geological
integrity and stability of a planet. The force and shock of a piece of rock crashing into a
helpless world can be enough to almost vibrate that world into action. So, for pure speculation,
we might imagine an asteroid coming down in the middle of the Pacific Ocean, or on the North
American east coast, but still releasing enough energy to tip the tectonic scales just enough so
as to set Yellowstone into motion, even if it’s hundreds of miles away. Then, not only would
there be all the expected, untold damage and ruin around that fabled volcano in north-west Wyoming,
but there’d also be an asteroid impact site elsewhere on Earth to deal with as well. Rather
than a single massive-but-combined problem, it’s two end-of-the-world events for the price of one…
and human beings would be extremely hard-pressed to foot that bill. In whatever way you look at it,
this is one doomsday scenario that any one person would be extremely unlikely to survive.
Do you think you could make it out alive? The good news is that, as scientists routinely assure us,
neither an asteroid strike nor a Yellowstone eruption is likely to happen any day soon,
or indeed, any lifetime soon… and so, the chances of both of them happening at the same
moment are incredibly slim. Thankfully, this is a hypothetical rather than a real-world issue. But,
nevertheless, that’s what would happen if an asteroid hit Yellowstone.