History of Solar System formation and evolution hypotheses occur in the interstellar material from which stars are born) formed the Sun and protoplanets, the latter splitting to form planets. The 2 portions can not remain gravitationally bound to each other, are at a mass ratio of at least 8 to 1, and for inner planets they go into independent orbits while for outer planets one of the portions exits the Solar System. The inner protoplanets were Venus-Mercury and Earth-Mars. The moons of the greater planets were formed from "droplets" in the neck connecting the 2 portions of the dividing protoplanet and these droplets could account for some of
Venus Atmospheric Maneuverable Platform of a lenticular shape which would significantly simplify packing, deployment sequence and structural mass, but it would not cruise so efficiently. The vehicle concept was also presented in May 2017 as a proof-of-concept for exploration of other planets and moons of the Solar System with an atmosphere. The 2013 preliminary concept envisions a suite of instruments NASA calls the 'Venus Flagship Design Reference Mission' for a balloon. Its mass is estimated at 20 kg and would require 50 W of electrical power to operate. The notional intuments consist on: There are ongoing discussions about possible NASA participation in Russia's Venera-D