After making sure your space crab is totally completely dead, season it with a pinch of salt and pepper, and maybe garlic or any herbs of you desired, lay it up side down on a cookie sheet.

preheat your oven to 600F for 5 minutes, put the crab in it for an hour. The hard shell of these space crabs are even harder than normal crabs, takes 3 times higher temperature and longer to cook. It's understandable that some of your home oven can't heat up to 600F, just let it heat up to 100F for 5 minutes, and then heat up to 500F for 5 minutes, works exactly the same ;)

Go watch some Sponge Bob and when the crab is ready, you'd hear the oven "ding" you.

photo taken by  F0x_T0dd