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5 votes
Accepted

(Fiction) How would a time traveler locate himself with 1962 technology?

Your semi-intuitive thought that there must be a pattern of the planet locations that would show the date is correct, I think. You won't need any special equipment but a sextant which will measure ...
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4 votes
Accepted

What programs do astronomers use to ensure their observatory control computer has accurate time?

There are two needs for accurate time in modern telescopes and instruments: A source of UT1-UTC for telescope pointing, An accurate source of UTC for timestamping of acquired data in cameras/...
  • 7,374
-4 votes

What programs do astronomers use to ensure their observatory control computer has accurate time?

You’re not in the subfield of ‘Time Transfer’, I see. No software is necessary; how do you think work got done before ~1950? Local oscillators were quite good before electronic computing, much less ...
3 votes
Accepted

Sidereal times occuring twice a day question

The algorithms for GMST avoids this ambiguity by using the number of Julian centuries of UT1 since J2000 (or some other epoch) rather than a time and date. It would only be a problem if someone gave ...
  • 2,857
5 votes

Maximum mass of the observable universe

Yes, the mass of the observable Universe increases from $\sim 0$ at Big Bang, asymptotically to a maximum of $\sim 10^{24} M_\odot$. The particle horizon The observable Universe is, at any time $t$, ...
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