It came from this fucknut right here.
https://en.wikipedia.org/wiki/Carl_Fl%C3%BCgge
Plus it's typically the minimum reliable resolution with perforning GPS/WiFi triangulation on your spyphone.
If you have a phone, you're being tracked.
Totally.
Earth days, idiot.
Do you live on Mars? Do you perceive and record time via its orbital and rotational periods? No, you don't.
You live on Earth and use its periods to perceive and record time.
KYS, idiot.