righto.com

To use the Montreal subway (the Métro), you tap a paper ticket against the turnstile and it opens. The ticket works through a system called NFC, but what's happening internally? How does the ticket work without a battery? How does it communicate with the turnstile? And how can it be so cheap that you can throw the ticket away...

"Different Globus units needed to be built for different orbits. Moreover, this design only handles circular orbits, making it useless during orbit changes such as rendezvous and docking. These were such significant limitations that some cosmonauts wanted the Globus removed from the control panel, but it remained until it was...