| Platlets are about a tenth of the size of erythrocytes. Sometimes up to one fifth the size, for big ones. Horizons on earth start at maybe 25 or 30 miles away. Cars are about 10 feet across. But you’re saying an 8 (maybe 6) micrometer erythrocyte, less than 10 feet away (on a car window), can eclipse a half a millimeter graphite pencil lead at a distance of 86Km (53 miles)? Also, a meter is a million micrometers. A millimeter is a thousand micrometers. You would need 100 copies of a 10 micrometer object, to span a millimeter. Fifty, to span half. Are you saying VY Canis Majoris is the erythrocyte to Triangulum’s pencil lead? As it eclipses said object at 53 miles? Or are you saying the erythrocyte is fixed onto a house window, and an erythrocyte can occlude the direct observation of an actual star in the sky (the biggest one we know of), even at 53 miles, which is over, beyond and even twice past any terrestrial horizon, and would need to be on a window in a skyscraper taller than anything ever built? EDIT: Sorry, the Burj Kalifa is 2,700 feet tall, so its spire would peek over the horizon, even at distances up to around 60 miles. So, I need to update my mental trivia model. We actually have built something that big, but it only happened about ten years ago. https://en.wikipedia.org/wiki/Burj_Khalifa |
Yes. Also, I'm pretty sure your objections here are handled by "(flat, obviously)". The point is to make an analogy to sizes and distances on a human scale, not to make a point about the geometry of Earth.