Setting the Clock: the Planet way, the navy way, and the w..

In article <ZNOdndvCQ5v-82PanZ2dnUVZ_qCunZ2d.RemoveThis@comcast.com>,
"Paul Howard" <ppaulshoward.RemoveThis@comcast.net> wrote:

> I was referring to the Ship Time being 'reset' when the Ship entered orbit
> at its Home System. Mind you, they would make sure that they were on the
> same time as a System/Planet they're visiting.

Synching to a planet they're visiting is problematic, since that planet
will have a different length of "day" than that used by the ship's
clocks. Unless the ship wants to rearrange all its watch schedules and
such, it will keep running on home system time.

Spacers will probably have watches that routinely keep two sets of time:
ship time, and whatever the local time system is.

--
Quando omni flunkus moritati
Visit the Buffy Body Count at <http://homepage.mac.com/dsample/>
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

Don Sample kirjoitti:

> Spacers will probably have watches that routinely keep two sets of time:
> ship time, and whatever the local time system is.

What, only two? I'd imagine they'd have at least a third one for a "flag
time" as well. After all, if you're on fleet maneuvers somewhere, you
may need to know what time it is for the fleet's main body even if
you're going off on a slightly different vector for a while.


Duh, I already had to keep three kinds of time once when I was just an
Army conscript the other decade in real life. Fortunately they were all
ticking at the same speed. (Zulu, Local and Home timezones.)
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

On 2008-04-10, Mikko Nahkola <mnahkola.DeleteThis@trein.ntc.nokia.com>
allegedly proclaimed to alt.books.david-weber:
> Don Sample kirjoitti:
>
>> Spacers will probably have watches that routinely keep two sets of time:
>> ship time, and whatever the local time system is.
>
> What, only two? I'd imagine they'd have at least a third one for a "flag
> time" as well. After all, if you're on fleet maneuvers somewhere, you
> may need to know what time it is for the fleet's main body even if
> you're going off on a slightly different vector for a while.

The problem here is how do you know what relativistic effects your local
headquarters is undergoing while you're off on your own?

--
Capt. Gym Z. Quirk (Known to some as Taki Kogoma) quirk @ swcp.com
Just an article detector on the Information Supercollider.
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

On Apr 10, 5:36 pm, Mikko Nahkola <mnahk....TakeThisOut@trein.ntc.nokia.com>
wrote:
> Don Sample kirjoitti:
>
> > Spacers will probably have watches that routinely keep two sets of time:
> > ship time, and whatever the local time system is.
>
> What, only two? I'd imagine they'd have at least a third one for a "flag
> time" as well. After all, if you're on fleet maneuvers somewhere, you
> may need to know what time it is for the fleet's main body even if
> you're going off on a slightly different vector for a while.
>
> Duh, I already had to keep three kinds of time once when I was just an
> Army conscript the other decade in real life. Fortunately they were all
> ticking at the same speed. (Zulu, Local and Home timezones.)


If you have to know "flag time", local system time is probably
irrelevant, so you set your shore time to flag time. If you are
haring off on a different vector than the flag, your clock is not
running the same speed, so the flag will have to cue you with a grav
pulse. If grav pulses are instantanous, it is possible to arrange for
things in different places to happen at the same time.
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

On Thu, 10 Apr 2008 14:44:28 -0500, "Paul Howard"
<ppaulshoward.TakeThisOut@comcast.net> wrote:


>
>I was referring to the Ship Time being 'reset' when the Ship entered orbit
>at its Home System. Mind you, they would make sure that they were on the
>same time as a System/Planet they're visiting.

i have the sneaking suspicion that it's all handled in the background
as computerized housekeeping with humans hardly being aware it's going
on.
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

I missed the Staff meeting, but the Memos showed that Brian McDonald
<Brian_knowspam.McDonald.RemoveThis@shaw.ca> wrote on Fri, 11 Apr 2008 00:46:20
GMT in alt.books.david-weber :
>On Thu, 10 Apr 2008 14:44:28 -0500, "Paul Howard"
><ppaulshoward.RemoveThis@comcast.net> wrote:
>
>
>>
>>I was referring to the Ship Time being 'reset' when the Ship entered orbit
>>at its Home System. Mind you, they would make sure that they were on the
>>same time as a System/Planet they're visiting.
>
>i have the sneaking suspicion that it's all handled in the background
>as computerized housekeeping with humans hardly being aware it's going
>on.

Bingo, had the man a Gold Plated No-Prize!

But the questions of what is done still remains.


tschus
pyotr
--
pyotr filipivich
The two oldest cliches in the book are "The Good Old Days were
better." and "After all, these are Modern TImes."
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

Don Sample wrote:
> Spacers will probably have watches that routinely keep two sets of time:
> ship time, and whatever the local time system is.
>
The Seaman Recruit chipping paint only cares about the local time when
he goes on liberty.

The planet's time zones are going to screw up the concept of "local
time" anyhow as a ship in orbit will probably be dealing with people on
opposite sides of the planet, making the local shift lengths a minor
complication.
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

Taki Kogoma kirjoitti:
> On 2008-04-10, Mikko Nahkola <mnahkola RemoveThis @trein.ntc.nokia.com>
>> Don Sample kirjoitti:
>>
>>> Spacers will probably have watches that routinely keep two sets of time:
>>> ship time, and whatever the local time system is.
>> What, only two? I'd imagine they'd have at least a third one for a "flag
>> time" as well. After all, if you're on fleet maneuvers somewhere, you
>> may need to know what time it is for the fleet's main body even if
>> you're going off on a slightly different vector for a while.
>
> The problem here is how do you know what relativistic effects your local
> headquarters is undergoing while you're off on your own?

Calculated from their last known intent. It'll of course diverge
whenever they do something unexpected, but you can also correct for that
with every transmission packet from them you see - if you do it right.
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

On Apr 11, 5:38 am, Spinner <nos... DeleteThis @nospam.net> wrote:

> I suspect there will be an equivalent to Zulu time, call it Universal
> Galactic Time kepty by automated means. Probably a galactic 'GPS'
> using a series of pulsars to generate 'absolute' time everybody agrees
> on. (Pulsar signals slow down at an extremely predictable rate, so its
> 'age' from a given point is predictable). Takes relativity out of the
> question since if pulsar 1A is 921828 42341399.93777 seconds old since
> some fixed date for you, that's "your" time. If command sent a note
> at 921828 42341399.93775 then you know how long ago it went. Also
> makes coordination fairly easy..
>

This fails for the simple reason that that no two star systems see the
same set of pulsars. On Alpha Centauri, practically adjacent to us in
stellar terms, the pulsars are all different ages, some by as much as
four years. Before establishing UGT between Sol and Alpha Centauri,
it must be insured that the benchmark age of each pulsar is in the
past of both systems. Therefore, it will take four years to set this
up, if detailed observations of precisely known age are not
available. If the infant Solarian League decided to institute UGT in
year 1PD, they may still be waiting for everybody's clocks to synch.

The coordination problem still requires some thought, as you cannot
check UGT while in hyperspace.
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

Don Sample <dsample.RemoveThis@synapse.net> wrote:

>In article <ZNOdndvCQ5v-82PanZ2dnUVZ_qCunZ2d.RemoveThis@comcast.com>,
> "Paul Howard" <ppaulshoward.RemoveThis@comcast.net> wrote:
>
>> I was referring to the Ship Time being 'reset' when the Ship entered orbit
>> at its Home System. Mind you, they would make sure that they were on the
>> same time as a System/Planet they're visiting.
>
>Synching to a planet they're visiting is problematic, since that planet
>will have a different length of "day" than that used by the ship's
>clocks. Unless the ship wants to rearrange all its watch schedules and
>such, it will keep running on home system time.
>
>Spacers will probably have watches that routinely keep two sets of time:
>ship time, and whatever the local time system is.

I suspect there will be an equivalent to Zulu time, call it Universal
Galactic Time kepty by automated means. Probably a galactic 'GPS'
using a series of pulsars to generate 'absolute' time everybody agrees
on. (Pulsar signals slow down at an extremely predictable rate, so its
'age' from a given point is predictable). Takes relativity out of the
question since if pulsar 1A is 921828 42341399.93777 seconds old since
some fixed date for you, that's "your" time. If command sent a note
at 921828 42341399.93775 then you know how long ago it went. Also
makes coordination fairly easy..

System time will only matter to landing parties and whoever aboard is
coordinating with the planetary government and its local time. (i.e.
the ISS doesnt change time to whoever it's above). The ship and fleet
will undoubtedly keep universal fleet time and live with the fact that
nothing is constant.

Note these problems really dont exist because FTL is not possible
without horrific causality violations anyway so "at the same time"
really doesn't mean anything.
--
2+2!=5 even for extremely large values of 2
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

Spinner <nospam.DeleteThis@nospam.net> wrote

> I suspect there will be an equivalent to Zulu time, call it Universal
> Galactic Time kepty by automated means. Probably a galactic 'GPS'
> using a series of pulsars to generate 'absolute' time everybody
agrees
> on. (Pulsar signals slow down at an extremely predictable rate, so
its
> 'age' from a given point is predictable). Takes relativity out of
the
> question since if pulsar 1A is 921828 42341399.93777 seconds old
since
> some fixed date for you, that's "your" time. If command sent a note
> at 921828 42341399.93775 then you know how long ago it went. Also
> makes coordination fairly easy..
>
> System time will only matter to landing parties and whoever aboard is
> coordinating with the planetary government and its local time. (i.e.

UGP seems a good idea, if it's really possible which I doubt.

Accuracy to a month or so would suffice for the following

The problem you wish to solve is to know where the planet you are
heading for *now is* in relation to its star and your planned emergence
from hyperspace so you don't have to come out, check and maybe go back
in. The local planetary "almanac" will tell you but that will be in
terms of local times and dates.

--
Mike D
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

rlbell.nsuid.TakeThisOut@gmail.com wrote:
> How old it is varies with location. The further away you are, the
> younger it is. Relativity is wierd that way. Travelling faster than
> light towards something is going forward in time,

I've often wondered what sort of theory of relativity a species without
the ability to detect electromagnetic radiation (light or heat) would
come up with.
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w.. 

On Apr 12, 2:34 pm, Spinner <nos....DeleteThis@nospam.net> wrote:
> "rlbell.ns...@gmail.com" <rlbell.ns....DeleteThis@gmail.com> wrote:
> >On Apr 12, 4:49 am, Spinner <nos....DeleteThis@nospam.net> wrote:
> >> "rlbell.ns...@gmail.com" <rlbell.ns....DeleteThis@gmail.com> wrote:
> >> >On Apr 11, 5:38 am, Spinner <nos....DeleteThis@nospam.net> wrote:
>
> <SNIP>
>
> >> You're missing the point. I dont care how old the pulsar looks to me
> >> (4 years).. I care how old it IS.
>
> >How old it is varies with location. The further away you are, the
> >younger it is. Relativity is wierd that way. Travelling faster than
> >light towards something is going forward in time, faster than it
> >elapses. Travelling away from something is travelling back in time.
> >Missed Live Aid? Go to a location in space where it is about to
> >happen and decode the broadcasts. Wish you could have seen the
> >formation of the Crab Nebula? There are places where that star is
> >about to go supernova. "Now" is a very location specific term.
>
> We're not defining "now" we're defining time. A pulsar at its surface
> has a very fixed and non subjective age. The variable is how old it
> appears to be, looking 1 year younger for every LY you move away from
> it. 1000 LY away, it LOOKS 1000y younger, but the star isn't any
> younger just because YOU are far away from it.

Go to what passes for a surface on Jupiter, where spacetime is curved
to about 2.5 times the acceleration of where you are likely to be as
you read this. Clocks run slower. If pulsars go down in frequency as
they age, they look younger when seen from Jupiter's surface, as there
is less time between the pulses (as measured by local clocks), even
though the difference in distance to the pulsars is practically zero.
Now for the mind bending part. Because the clocks run slower, less
time has elapsed, so the pulsars seen from the surface of Jupiter do
not just look younger, they really are younger. You can argue all you
like, it will not matter, as when you go to Jupiter and make the
observations, the data will match the jovian claims.
>
> If I see that 2000 APPARENT years have passed since a pulsar was
> discovered (discernable from its pulse rate observed where I am), and
> i know i'm 1000 LY from the pulsar, then i know that 1000 'real'
> years, at the pulsar's surface, have actually passed, since i'm seeing
> pulses that left it 1000 years ago. That gives me its absolute local
> age. And that gives me a measuring stick.

No. There is no such thing as a 'real' year. The very concept
presumes the existence of an absolute frame of reference that is
already known to be impossible. All you know is that 2000 apparent
years have passed. You do not even know how long that period of
elapsed time is, at your current location. The next step is to look
at the planet where the discovery was made (assuming it can be seen by
your instruments) and watch it long enough so that you know what its
orbital period is, with enough precision to know how to correct your
measurements of time to match. Once that is done, you need to
recalculate distances because the difference in local time also means
differences in locally observed distances.

Time as measured at the surface of the pulsar is something else,
entirely. As pulsars are much more massive than Jupiter, their clocks
run even slower. Supermassive black holes have both lasted for eons,
and are less than a second old, it depends on where the observer is
when the mesurement was taken. This was the background story for the
series Andromeda. The High Guard cruiser Andromeda tries to evade
attackers in the vicinity of a black hole and ends up coming out of
the gravity well after a few seconds, or several hunded years,
depending if you checked the ships' chronometer or the history books.
>
> Remember, we're talking about plus or minus a few weeks or months here
> -- there is no point or use to synchronicity across 2000LY any closer
> than that since there is no common "now" that matters anyway.
>
> However, you can build galactic reference clock systems, just takes a
> little math.

If the time is +/- weeks or months, I would hardly call it a
reference. Pulsars do not work due to the difficulties needed to
figure out local time. If you have instruments that can see orbiting
planets, at interstellar distances, you set your calendar by the one
that everyone can see. Actually, a binary star is probably better, as
the orbits are longer, and they are easier to see. There is still
some number crunching and guesswork. With more binary sets with
dfferent periods, it becomes easier to figure out references.
Comparing observed periods from different locations of the same binary
set tells you how fast the clocks are running relative to ech other.
 >> Stay informed about: Setting the Clock: the Planet way, the navy way, and the w..