xkcd #3298: Aerospace Flowchart
Title text:
Someday, we will find the problem that goes with this solution.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3298/
Slap a camera and a bunch of batteries on a balloon and you can easily map large areas without recharging. Great for photogrammetry. You can also carry other instruments onboard.