"The electromagnetic radiation that streams out of the Sun is a hailstorm of photons. The x-rays are like bowling-ball-size hailstones: potent, but thankfully rare. The radio photons are like the very smallest hailstones: puny, and also relatively uncommon. Visible-light photons are like your average-size hailstones: neither especially strong nor especially weak, and by far the most common."

and

"If photons of light are like raindrops, then telescopes are like buckets."