The other day, a live World War II hand grenade was found in a garden just down the street from my house. Thirty families were evacuated from their homes in the middle of the night while the army bomb disposal unit came along to do their stuff. This is very unusual around where I live. For one thing, Ireland wasn’t in World War II, so how there came to be leftover weaponry lying around is something of a mystery. Nonetheless, for those who could have been affected, it’s a little scary to think that a live hand grenade could have detonated in a suburban housing estate.

By coincidence, today I came across this website, which enables you to simulate a bomb explosion in any part of the world. And not just any old bomb explosion, but a nuclear bomb explosion. All you need to do is point the little red arrow somewhere on Google Maps, select your kiloton yield, and — as might be expected from a website-based apocalypse dashboard — click on a button marked ‘Detonate‘. And there you go. The software returns an image showing the blast radius in various concentric degrees of severity.

So I did what any red-blooded man in my position would do. I plonked the target right down on top of my own house, selected the biggest bomb available (the pimped-up 100-Mt version of the USSR’s Tsar Bomba), panned back so that I could see the full fallout, and then, Strangelove-like, did the whole yippy-ki-yay bit.

The simulation shows that the entirety of Galway, the city I live in, was blown away in a fireball, its outer hinterland devastated by radiation and airblast. Thermal radiation causing firestorms and melted skin swept all the way up the motorway as far as Athlone. People living in Dublin were fine, of course, which is just typical.

Hypothetical or not, I must admit I found that level of destruction relatively modest. After all, I did select the biggest thermonuclear weapon imaginable. In fact, it is so imaginable it doesn’t even exist (merely having been ‘designed’ rather than ‘built’ by the USSR). When I ran the simulation using the American h-bomb ‘Castle Bravo‘ — which has the advantage of actually existing — skin melted only as far as Loughrea. Meanwhile, a ‘crude nuclear terrorist weapon’ simply blew up my house, with deadly radiation drifting only 500 metres, not even reaching the local shop.

The process of calculating and plotting the various outcomes is based on projections produced by Carey Sublette, a secretive American computer scientist and weapons analyst. His work also includes The Nuclear Weapons Archive, a sobering encyclopaedic archive of information and statistics about the world’s nuclear arsenal. It is important to note that the calculations show the destruction of the big bangy bit of a nuclear attack — they do not show how many people would be affected by radioactive fallout in the years after the impact.

All of this is very terrible of course. But fun. And informative. So I did it again. And again. And I dare you not to do so too. Here’s that link once more.

Have a blast.

Brian Hughes

Brian Hughes is an academic psychologist and university professor in Galway, Ireland, specialising in stress, health, and the application of psychology to social issues. He writes widely on the psychology of empiricism and of empirically disputable claims, especially as they pertain to science, health, medicine, and politics.