URAGAN RELAKSATSIA MOLNIYA-SM VSPLESK IMPULS PLASMA-PROGRESS . ... Investigation of optical phenomena in atmosphere occurring during re-entry of bodies into rarefied upper atmosphere. ... Investigation of lightning discharges in the Earth's atmosphere and lower ionosphere. ... Modification of ionosphere by pulsed plasma sources. Plasma-Progress . Investigation of reflecting characteristics of spacecraft plasma environment with the onboard thrusters operating by the ground observation facility. ...