Proton's Long-Awaited Comeback Mission

Russia's Proton Rocket is ready for a long-awaited return to flight mission, almost a full year after the heavy-lifter last took flight from its remote Kazakhstan launch base. The vehicle was kept on the ground after potential weaknesses were discovered on the rocket's second and third stage engines - requiring a lengthy refurbishment process.

Carrying EchoStar-21, the Proton-M is targeting liftoff on June 8, 2017 on an all-day ascent mission that begins with a ten-minute ride on the three-stage Proton before the Briz-M upper stage takes over for a five-burn, nine-hour mission profile.

Live Video by Roscosmos / Tsenki (Live ILS Launch Coverage)