Live coverage of the countdown and launch of a Proton rocket and the Inmarsat 5 F3 mobile communications satellite. Text updates will appear automatically below; there is no need to reload the page. Follow us on Twitter.
A modified Russian missile built for nuclear war blasted off on a peaceful mission Friday, targeting placement of a European Earth observation satellite in orbit to measure atmospheric chemistry and global air quality. Liftoff from the Plesetsk Cosmodrome in northern Russia occurred at 0927 GMT (5:27 a.m. EDT).