 The physics of the radar and in the atmosphere. So there's weak rotation. It might be only a couple of miles per hour. And again, if you've ever been in a dust devil, you know, dust devils typically are 10, 15, 20 miles per hour. Now, if you've been in the desert southwest, some of those dust devils are pretty amazing, 30, 40 miles per hour. And they'll pick stuff up 10, 20,000 feet.