Placed into an orbit with an apogee of 185,000 kilometres (115,000 mi) it could make observations outside the Earth's umbra and radiation belt. Among the most important observations by Astron were those of the SN 1987A supernova on March 4–12, 1987 and of Halley's Comet in December, 1985, that allowed a group of Soviet scientists to develop a model of the coma surrounding Halley's Comet.
Payloads are separated by bullets ( · ), launches by pipes ( | ). Manned flights are indicated in bold text. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in (brackets).