It was here that the first automated sample return took place via the Luna 16 probe,[2] in September 1970.

Sinus Successus lies along the eastern edge of the mare.

Unlike many other maria, there is no mass concentration (mascon), or gravitational high, in the center of Mare Fecunditatis.

Mascons were identified in the center of other maria (such as Serenitatis or Imbrium) from Doppler tracking of the five Lunar Orbiter spacecraft in 1968.

[3] The gravity field was mapped at higher resolution with later orbiters such as Lunar Prospector and GRAIL, which unveiled an irregular pattern.