Elon Musk was asked about one of the hardest problems that he was dealing with at SpaceX. Its massive starship had to cut weight everywhere it could so that the cost of each launch could become low enough for all-day launches. Step one to cutting weight was cutting out the landing gear. So now rather than the rocket returning to earth and landing on its own, a new design means that it comes down to earth with its bottom exposed. And just before hitting the ground, this tower shoots out two enormous rods that grab the rocket like a parent that's catching a falling child.