proton is an expandable launch vehicle used for both commercial and russian government launches. it is still in use as of 2018. all protons are built at khrunichev state research and production space center, and are then launched from baikonur cosmodrome. it can launch around 22.8 tonnes to low earth orbit, and it can launch around 6.3 tonnes to geostationary orbit. it is expected to be retired before 2030.