NASA’s Magellan space probe, still orbiting Venus since 1990, enters a phase of slightly riskier experiments, dipping its solar panels into the upper reaches of the Venusian atmosphere and firing its reaction control engines to keep from spinning out of control. This allows for studies of the composition of Venus’ atmosphere, as well as studies of the vehicle’s behavior as it resists atmospheric friction. The results of the “windmill” experiment inform the design of future Mars probes which will need to aerobrake to slow down and enter the Martian atmosphere.
