Hacker News Reader

I saw something once that explained how the powerful magnification seems silly until you account for the angles that things are at.

The example they used was that license plates are vertical so to read them the satellite can't be directly above the car so it's actually a much further distance and greater magnification is necessary because of the atmosphere and the distortion of reading something at an angle.

View on HN

More that the satellites are in fixed orbits that are relatively low (250 km) and moving at thousands of km per second. Even if the target is directly below them, they need to rotate quite a lot to see it for more than a few seconds at a time. If the target isn't directly below, they need to look much farther sideways than down.

Slight typo there: "thousands of km per second", you probably meant "thousands of meters per second". Low orbit is on the order of 7-8 km/s. I did find the typo humorous.

most spy satellites aren't geostationary?

No.

Reply on news.ycombinator.com