Anyone that’s ever tried to plan an outdoor activity in advance knows that weather forecasting is not an exact science, but the perpetual sky-watchers at NASA may have inadvertently found a way to improve these guesstimations. 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. Read the full story at Engadget.