Probably easier option is just redirecting an asteroid bigger than Chicxulub impactor. But the point is that even that is not enough to eradicate life. As I sa

Probably easier option is just redirecting an asteroid bigger than Chicxulub impactor. But the point is that even that is not enough to eradicate life. As I said, you would need something like Late Heavy Bombardment or Venus like greenhouse effect and even that may not be enough. Based on the Moon craters Late Heavy Bombardment would include: - 22,000 or more impact craters with diameters >20 km (12 mi), - about 40 impact basins with diameters about 1,000 km (620 mi), - several impact basins with diameters about 5,000 km (3,100 mi) It's also important to highlight that everywhere were our ancestors appeared soon after megafauna population got reduced by 20% - 70%: https://en.wikipedia.org/wiki/Holocene_extinction#/media/File:Extinctions_Africa_Austrailia_NAmerica_Madagascar.gif https://en.wikipedia.org/wiki/Holocene_extinction#/media/Fil... In the last 100 years we just entered path to near total eradication of megafauna. E.g. wild mammals account now for ~4% of mammals biomass. Complex life is nowhere near as robust as simple life forms.