Vega mission

Probe designed for investigations of the planet Venus and Halley's Comet. Original plans called for two
versions, 5VS and 5VP. The 5VP Venus orbiter would be a relay station for a big Soviet-French balloon, to be
dropped into the Venusian atmosphere by the 5VP Halley's comet probe as it flew by Venus. In 1981, it was
decided to cancel the 5VS orbiters and redesign the 5VP to expand the Halley research programme (this may
have been in response to the cancellation of the US Halley probe the same year).