It was a dark and stormy night,,, <sorry> and I was gazing at the rain in the beam of a Mag85, when I noticed something interesting.
Some of the rain drops appeared to pulse on their way down in the beam of my light, while others (in the same beam and at the same time) were constantly "ON." It occurs to me that this may need some ellaboration to explain.... Many rain drops appeared as straight streaks at some angle towards the ground, and this is something I understand. I have some persistence of vision built into me. That is OK. They are like this: ----------------, meaning an uninterrupted straight streak. Other rain drops toggled between reflective and non-reflective at _regular_intervals_ on their way to the ground, like this: -- -- -- -- --. Some pulsing rain drops did so at different rates than others, but each one at a constant rate.
What's it all about?
My only thought was that either the shape or orientation of the rain drop is cycling. However, I would expect that to lead to a more gradual fading in and out of reflectivity, and not the hard pulsing that I saw. Still, that's the only possibility, isn't it. ? For example, maybe the shape of the drop is oscillating between fat and skinny, as bounded by the surface tension of the skin of the rain drop. ? If that is so, then the different rates I see would be the "resonant frequencies" for shape-bouncing of each rain drop, which would relate to the SIZE of the rain drop. In other words, the slower-oscillating drops would be the larger ones. eh?
Has anyone else noticed this? Is there some terribly obvious explanation that I did not know? Should I go see my optometrist now?
Some of the rain drops appeared to pulse on their way down in the beam of my light, while others (in the same beam and at the same time) were constantly "ON." It occurs to me that this may need some ellaboration to explain.... Many rain drops appeared as straight streaks at some angle towards the ground, and this is something I understand. I have some persistence of vision built into me. That is OK. They are like this: ----------------, meaning an uninterrupted straight streak. Other rain drops toggled between reflective and non-reflective at _regular_intervals_ on their way to the ground, like this: -- -- -- -- --. Some pulsing rain drops did so at different rates than others, but each one at a constant rate.
What's it all about?
My only thought was that either the shape or orientation of the rain drop is cycling. However, I would expect that to lead to a more gradual fading in and out of reflectivity, and not the hard pulsing that I saw. Still, that's the only possibility, isn't it. ? For example, maybe the shape of the drop is oscillating between fat and skinny, as bounded by the surface tension of the skin of the rain drop. ? If that is so, then the different rates I see would be the "resonant frequencies" for shape-bouncing of each rain drop, which would relate to the SIZE of the rain drop. In other words, the slower-oscillating drops would be the larger ones. eh?
Has anyone else noticed this? Is there some terribly obvious explanation that I did not know? Should I go see my optometrist now?
