https://www.reuters.com/article/us-space-exploration-blue-origin-nasa/musk-bezos-collide-after-spacex-wins-moon-landing-contract-idUSKBN2CD2TI >(Reuters) -Blue Origin, the space rocket company backed by billionaire Jeff Bezos, is formally challenging the $2.9 billion moon lander contract awarded by NASA to rival Elon Musk's SpaceX.