SpaceX drops plan to upgrade Falcon 9 to Mars rocket version

Elon Musk on Sunday said that his startup SpaceX has dropped plans to build a mini version of its Mars rocket 'BFR' by upgrading the second stage of its Falcon 9 rocket. Musk further said the rocket will get "minor tweaks to improve reliability only, provided NASA & USAF are supportive." SpaceX is working on "accelerating BFR instead", Musk added.