It's not possible to quench thirst on the moon by microwaving regolith (lunar soil). While regolith contains some water molecules trapped within its minerals, the amount of water present is extremely low, and it's not practically feasible to extract it using a microwave or any other means.

The lunar regolith is primarily composed of oxygen, silicon, iron, magnesium, aluminum, and calcium. The concentration of water in regolith varies depending on the region and the depth at which the sample is taken, but it is generally estimated to be less than 1%. Furthermore, the water molecules in regolith are strongly bound to the soil's minerals, making them challenging to separate.

To obtain water from regolith, complex processes involving heating the soil to extremely high temperatures and chemically treating the resulting material are required. These processes would require sophisticated equipment, a continuous source of energy, and specialized materials, all of which are currently beyond our capabilities for lunar exploration.

Moreover, the process of extracting water from regolith is energy-intensive and requires specialized technologies, making it impractical for immediate human consumption. Therefore, astronauts in space missions have to rely on carefully managed water supplies and recycling systems rather than extracting water from the lunar regolith.