Did you enjoy that planetary impact simulator I linked to a while back? Did you enjoy it, perhaps, a little too much, and feel that your galactic karma could do with a bit of balancing? Well, what better way to atone for smashing planets to bits than by building new ones, which is exactly what NASA’s Planet Makeover webapp lets you do [via BoingBoing]. A bit of random fun for friday afternoon: adjust planet size, orbital distance, solar type and planetary age, then hit the button and see whether you’ve made a habitable world. [SPOILERS: your odds of doing so are very low. Good afternoon, Professor Drake!]

Not a new idea, of course (I had a serious hankering for a copy of SimEarth back at the start of the nineties, but never got one), but NASA have wisely brought the idea kicking and screaming into the Twentyteens by a) simplifying it and putting it on the web for free and b) using the word EXTREME! in the name.