They have been testing a laser system for measuring lunar dust and soil kicked up by rocket exhausts, and while using precipitation as a substitute to calibrate the laser, they found they could measure the average size of raindrops passing through it.
With its superior lift capability, the SLS will expand our reach in the solar system and allow us to explore cis-lunar space, near-Earth asteroids, Mars and its moons and beyond.
If the moon harbours ice, for example, measuring the amount of it at different depths could enable planetary scientists to work out the rate at which comets smashed into the lunar surface over its history, and that knowledge could then be plugged into models of the formation of the solar system.