Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-05 Thread Tony Finch
Clive D.W. Feather cl...@davros.org wrote: Another way is to have TAI hours and minutes and seconds, with each day ending with a partial hour. Digital time displays would have no problem with this, calculators can be used if you actually need to work out how long an interval stretching over

Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-05 Thread Clive D.W. Feather
Tony Finch said: Another way is to have TAI hours and minutes and seconds, with each day ending with a partial hour. This is the arrangement in Kim Stanley Robinson's Mars trilogy. And the Honor Harrington books, which is where I got it from. -- Clive D.W. Feather | If you lie to

Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-04 Thread Clive D.W. Feather
The length of a Martian solar day is currently about 88775.24409 s (per Wikipedia), yielding an average minute length for a UTC equivalent of 61.6494751 s. On Paleoterra you'll want an average minute length somewhere between 58.0 s and 59.4 s. So on Mars you'll want about 65% of minutes

Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-03 Thread Zefram
Daniel R. Tobias wrote: length of the day, but it was shorter than the current day, which would, I imagine, have an impact on timekeeping in this colony. The magnitude of this difference is in the same ballpark as the present difference between Terran and Martian days, so exactly the same range

Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-03 Thread Rob Seaman
Sending this from the Super-80 on route to the Philadelphia UTC meeting. On Oct 3, 2011, at 3:50 AM, Zefram wrote: Lots of things I agree with. A couple of comments below. Daniel R. Tobias wrote: length of the day, but it was shorter than the current day, which would, I imagine, have an

Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-03 Thread Zefram
Rob Seaman wrote: If not sexagesimal then what? Could humans actually use a decimal counter productively? The decimal day is quite practical. It doesn't catch on on Earth, of course, because of the network effect favouring interoperability with the existing sexegesimal division. On a new

Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-03 Thread Warner Losh
On Oct 3, 2011, at 8:15 AM, Rob Seaman wrote: I'm taken by your mention of Hertz as the unit of TAI. That's an interesting way to break the artificial symmetry between the two meanings of the word second. Might be some play there. The unit of atomic time is frequency, the unit of civil

Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-03 Thread Steve Allen
On 2011 Oct 3, at 07:15, Rob Seaman wrote: Sending this [...] on route to the Philadelphia UTC meeting. ditto the moon was absolutely colossal in the sky They must have arrived in September and that was the harvest moon One hopes that by year 2149 we'll have a good answer for the topic of

[LEAPSECS] What timekeeping system should the Terra Nova settlers use

2011-10-03 Thread Hal Murray
How would the people on this list who advocate for various treatments of future timekeeping in our own world deal with that situation? Fun question. Thanks. I'd setup two separate timekeeping systems. For measuring time (and frequency) in scientific experiments, I'd use some fixed unit and

Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-03 Thread Warner Losh
On Oct 3, 2011, at 11:03 AM, Rob Seaman wrote: On Oct 3, 2011, at 9:20 AM, Warner Losh wrote: On Oct 3, 2011, at 8:15 AM, Rob Seaman wrote: I'm taken by your mention of Hertz as the unit of TAI. That's an interesting way to break the artificial symmetry between the two meanings of the

Re: [LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-03 Thread Rob Seaman
On Oct 3, 2011, at 10:46 AM, Warner Losh wrote: For Electrical Engineering, nobody cares about earth angles, but they do care that all seconds are the same length. It depends what project the electrical engineers are working on. Astronomical projects employ plenty of engineers. The

[LEAPSECS] What timekeeping system should the Terra Nova settlers use?

2011-10-02 Thread Daniel R. Tobias
I watched the premiere episode of Terra Nova, a new science fiction TV series, last week. The premise is that people are escaping a dystopian future (of the overpopulated, overpolluted, repressive sort standard in sci-fi movies at least as far back as Soylent Green) by going through a