Pioneer Venus Orbiter
It was launched by America on 20 th May 1978 on Atlas-Centaur Launch Vehicle. It had the mass of 517 Kg. and solar array of 312W was used for power. The following equipments were boarded on it for experiments :
Cloud photo polarimeter to study about clouds.
An electric field detector to study the solar wind and interactions.
A magnetometer to detect magnetic field Venus.
A solar wind plasma analyzer to measure properties of wind.
A charged particle retarding potential analyzer to study atmospheric particles.
Sunday, on 8 th Aug. 1978 , another “Pioneer Venus Millipore” was launched having 290 Kg. bus mass, 315 Kg. large probe mass with each small probe mass equal to 90 Kg.
It contained temperature, pressure and acceleration sensors, a nephelometer to search for cloud particles, a neutral mass spectrometer to measure the atmospheric composition etc.