Please...
The entire nuclear arsenal of the planet at the heighth of the cold war (~50,000 Mt) fabricated into one bomb would hardly make a noteworthy new crater on the moon aside from the fact that the surface in the blast area would be vitrified and reflect some more light.
Major extinction events here have been in association with energy releases on the line of 200,000,000 Mt, and while it screwed the earth up, it came no where near destoying it, or all life on it for that matter (which would actually probably take reliquifying the lithospere to a depth greater than 1 mile).
I suspect if we put a crash program on it we could develop a bomb that would do more than that. I’m not saying we’ve got one ready in the garage.