Probably the reason you don't stick your name on a pen drive etc
NASA Scientist Debunks Claims That Interstellar Object Comet 3I/Atlas Is An Advanced Alien Spacecraft | IFLScience https://share.google/LfPhjaPDz4xcuFweW
May I ask which magazine or book this paragraph if from?
I must admit though, for a mission to Mars timekeeping would probably be the least of their problems. How to keep the crew alive for almost two years? Oxygen supply? Power supply? Water supply? Food? Grow their own food on board? Recycle waste water to water food plants? How to minimise muscle wasting and osteoporosis during prolonged space flight? Lots of things to think about...