Elon Musk @elonmusk
@RationalEtienne @thesheetztweetz @BryceSpaceTech @SpaceX @roscosmos @Arianespace @ArianeGroup @northropgrumman @RocketLab @ulalaunch @VirginOrbit @torybruno Mass to orbit is the fundamental metric for making life multiplanetary — PolitiTweet.org