Vesta (spacecraft)

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Vesta was a planned multiple-asteroid-flyby mission that the Soviet Union assessed in the 1980s. The Vesta mission would have consisted of two identical probes (just like earlier Soviet Venus missions), to be launched in 1991. Similar to the Vega program, each spacecraft would deploy one or more landers or balloons into the Venusian atmosphere, and then proceed to its next target.

At Venus, a French satellite dedicated to asteroid flybys would be released. It would return for an Earth gravity assist, and then reach about 3–3.3 au from the Sun. There they would fly by some smaller asteroids, and Vesta, if possible, with a small probe landing there.

The exact targets would depend on the launch date. In the initial 1985 study, 2700 possible trajectories were analyzed for a launch date in 1991/1992. Considering all constraints, about 12 candidate trajectories were selected. The two identical spacecraft could have different trajectories and targets. These included 5 Astraea, 53 Kalypso, 187 Lamberta, 453 Tea, 1335 Demoulina and 1858 Lobachevskij, and comet Encke.