CROWD SIZES: Several people have sent emails like this one:

I’m always bothered how we don’t know how many people really go to these

protests. What about satellite photos?

Those would be interesting. In fact, I contacted someone I know at SpaceImaging to see if they’d done that. Mostly they only take pictures in response to orders from cash customers (it’s cheaper than it used to be, but still expensive) but they sometimes shoot stuff like that and make it available on their site. Not this time, alas.

Even then, it’s hard. You either have to count a few samples and extrapolate (which is iffy, since crowds aren’t uniformly dense, though that’s addressable to some degree) or count everyone, which requires, well, counting everyone.

Heck, even counting website traffic gives people fits.