Jupiter Magnetospheric Orbiter the orbiter was proposed for a lift-off in 2020 together with ESA's Jupiter Ganymede Orbiter (JGO) from which it would undock upon its arrival at Jupiter in 2025/2026. However, the EJSM collaboration was disbanded and NASA renamed its initiative with Europa Multiple-Flyby Mission, ESA's Jupiter Icy Moon Explorer, and Roscosmos's Laplace-P. The JMO objective was to undertake detailed "in situ" studies of the magnetosphere of Jupiter as a template for an astrophysical magnetised disk for "3-point" investigations of the Jupiter system via synergistic observations with other orbiters. The size and weight of the JMO would have been limited to carry
Origin of the Moon might have been a large atmosphere around the primitive Earth, which would slow the movement of the Moon by natural aerobraking before it could escape. That hypothesis may also explain the irregular satellite orbits of Jupiter and Saturn. This hypothesis also has difficulty explaining the essentially identical oxygen isotope ratios of the two bodies. This is the now discredited hypothesis that an ancient, rapidly spinning Earth expelled a piece of its mass. This was proposed by George Darwin (son of the famous biologist Charles Darwin) in the 1800s and retained some popularity until Apollo. The Austrian geologist Otto Ampherer in