On June 8, 2017 at 03:45 UTC the Russian "Proton-M” rocket-carrier was launched from Baykonur Cosmodrome. The rocket equipped with the "Briz-M” booster orbited the “Echostar-21” telecommunication satellite. Built by Space Systems/Loral in Palo Alto, California, the “Echostar-21” satellite weighed around 6,9 tons, making it one of the most massive commercial communications spacecraft ever launched, and the heaviest commercial payload ever flown on a Proton rocket.