Max Planck Institute for Solar System Research the clouds and winds of Venus. Microwave instruments determine the composition of atmospheres while infrared spectrometers examine surface rocks. A novel laser altimeter on board BepiColumbo will survey the topography of Mercury to within a meter. Further MPS instruments identify the atoms, electrons, and dust that move around the planets and impact their moons. Here the influence of the solar wind on the atmospheric gases is of particular interest. Theoretical studies and intensive computer simulations help to understand the processes both inside and surrounding the planets and to interpret the measured data. Models developed at MPS can describe, for example,
Venus study, another impact reversed the planet's spin direction and caused the Venusian moon gradually to spiral inward until it collided with Venus. If later impacts created moons, these were removed in the same way. An alternative explanation for the lack of satellites is the effect of strong solar tides, which can destabilize large satellites orbiting the inner terrestrial planets. To the naked eye, Venus appears as a white point of light brighter than any other planet or star (apart from the Sun). The planet's mean apparent magnitude is -4.14 with a standard deviation of 0.31. The brightest magnitude occurs during