Speaker
Description
Unmagnetized or weakly magnetized solar system planets located in the supersonic solar wind often have a shock that slows down the wind to sonic speed. The region between the shock and the planetary plasma, known as the sheath, thermalizes the shocked solar wind. At Earth, the sheath is thick and limits the high-frequency solar wind modulations reaching the magnetopause and the planetary plasma inside. For planets without an intrinsic magnetic field, such as Mars, the solar wind is not fully thermalized in the sheath, and the modulations in the solar wind can directly impact the planetary plasma domain. During non-storm times, there are special solar wind conditions that result in efficient coupling between the solar wind and the planetary thermosphere, driving the system. These conditions are important for planetary evolution, but likely not important for climate. However, for space weather, these events could impact the environment at similar levels as storm times. The observational signatures of these events will be presented and discussed with respect to how they could impact human activity at their planetary objects.
