A four-tonne chunk of debris the size of a school bus from a SpaceX rocket has crashed into the Moon, according to tracking data, creating a new crater on the lunar surface and providing scientists a rare look at high-velocity cosmic impacts. It struck the lunar surface with the force of roughly three tonnes of TNT. Such rocket hardware typically re-enters Earth’s atmosphere to burn up or splash down into remote ocean zones after delivering payloads into orbit. SpaceX said the trajectory leading to the crash was unintentional but unpreventable, given the vehicle’s remaining fuel reserves. Wednesday’s collision marks only the second known instance of discarded rocket space debris accidentally crashing into the Moon.