4 ms·
Time is local to a region though - there isn't any "Solar System Coordinated Time".
by ghshephard 6y ago
Time is local to a region though - there isn't any "Solar System Coordinated Time".
- hedora 6y agoJust hold still and avoid gravity wells. It’ll work out.
- nuccy 6y agoWhat is hold still? Relatively to what? Everything moves relatively to each other with a planet, solar system, galaxy, galaxy cluster, supercluster, filament, Universe...
- imoverclocked 6y agoI guess pulsars may be our best bet for a universally coordinated time? We can detect the passage of time in a gravity well and create a well-centric system if need be!
- nuccy 6y agoWell, no, pulsars periods drift due to change of alignment and emission process over time. Thought special and general relativity will drive any "global/solar system/galaxy"-wide precise time useless on long term anyway. The best is to keep track of long enough common measures ("day", "month") with decimal/fractions being connected to actual local times.
- imoverclocked 6y agoThe Earth “day” also drifts over time. If you’ve ever thought today was longer than the last, then you are statistically correct!
- gorgoiler 6y agoAre you saying that a given pulsar acts as a giant sky clock? And that because it is far away — for some large value of far — it means that any clock inconsistencies across the solar system can be compensated for?
- imoverclocked 6y agoPretty much, yes! Obviously the speed of light and orbital motion/distances make things tricky but not impossible. I think I’m also saying that since time passes at different rates in different gravity scenarios, a single external reference may be the best way to coordinate time… even outside of our solar system.
- imoverclocked 6y agoActually, “single external reference” might be wrong here. Using multiple pulsars might give us a better fix for our position +time solution across large distances.
- imoverclocked 6y agoEven cooler is that this has apparently and unsurprisingly already been explored.
- gorgoiler 6y agoThese replies are intriguing, thanks. Do you have some good links / references I can follow?
- imoverclocked 6y agoPulsar positioning system: https://arxiv.org/pdf/1704.03316.pdf https://arxiv.org/pdf/1704.03316.pdf While not a primary source, it's still an answer to absolute time from pulsars: https://physics.stackexchange.com/questions/175981/can-you-use-pulsar-observations-to-determine-absolute-time-how-long-can-you-go https://physics.stackexchange.com/questions/175981/can-you-u...