a way to write words inside a liquid Timothy Collinson (12 May 2023 14:04 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Alex Goodwin (23 May 2023 09:03 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Timothy Collinson (23 May 2023 21:31 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Jeff Zeitlin (23 May 2023 21:55 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Alex Goodwin (24 May 2023 02:21 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Timothy Collinson (24 May 2023 15:10 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Richard Aiken (25 May 2023 00:06 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Greg nokes (26 May 2023 20:05 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Richard Aiken (28 May 2023 04:29 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Tom Rux (28 May 2023 12:24 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Greg nokes (28 May 2023 16:02 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Jeff Zeitlin (29 May 2023 02:11 UTC)
Re: Tides [was Re: [TML] Messages in Jumpspace Richard Aiken (30 May 2023 12:45 UTC)

Re: Tides [was Re: [TML] Messages in Jumpspace Alex Goodwin 23 May 2023 09:02 UTC

On 23/5/23 06:29, Timothy Collinson - timothy.collinson at port.ac.uk
(via tml list) wrote:
>
>
> On Sat, 20 May 2023 at 23:19, David Johnson - piperfan at zarthani.net
> <http://zarthani.net> (via tml list) <xxxxxx@simplelists.com> wrote:
>
>     Hi Timothy.
>
>>     I've often thought Jumpspace could be more 'interesting' although
>>     the best I've come up with
>     [snip]
>>     is perhaps the idea of 'tides' making arrivals and departures
>>     from worlds a bit more 'limited' in terms of timings.  I like the
>>     idea of a dramatic "we sail with the tide..." and perhaps role
>>     playing opportunites/problems around when exactly a ship departs.
>
>     I like this idea; it's a great storytelling concept! Doesn't even
>     have to be some "special aspect" of jumpspace, perhaps just the
>     complex interaction of the world's gravity field, the primary
>     star's gravity field and the gravity field of a large, Luna-like
>     satellite (and perhaps other bodies in the system as well) messing
>     with distance -- and therefore the time required -- to get to the
>     "100 diameter limit." Indeed, I imagine this is a pretty common
>     situation for worlds which are themselves satellites of a
>     "super-earth
>     <https://exoplanets.nasa.gov/what-is-an-exoplanet/planet-types/super-earth/>"
>     or a small gas giant.
>
>
> Yes, I did think it could just 'be' rather than have an explanation
> for it.
> I was trying to think of a simple way of implementing it.  But if I
> wrote notes to myself, I can't find them.
>
> I think my thinking was along the lines of a table that would give:
> no tides (Jump any time) - very rare
> two tides a day - commonest
> four tides a day - less common
> six tides a day - rare
>
> So, I suppose something like a 2D6 table:
>
> 2 1D6=1: 1 tide/week, otherwise one tide every other day
> 3 one tide
> 4 one tide
> 5 two tides
> 6 two tides
> 7 two tides
> 8 two tides
> 9 four tides
> 10 four tides
> 11 six tides
> 12 no tides - come and go any time
>
> A day being defined as a 24 hour period for no reason any recalls
> except history.  (Or is it known in the OTU that it comes from Terra's
> day?  I can't recall.)
>
> Ship's can Jump an hour(?) either side of 'high' tide. Up to an hour
> beyond that risks a DM+1 to misJump.  Two hours beyond that DM+2 etc.
> How do v
> Does that cover all that's needed?  (I suppose you could do something
> complicated like having the 100D limit vary (in and out) with the
> tides but I was trying to keep it simple. Or perhaps that's what makes
> Jumping closer than 100D more dangerous.)  Another variation might be
> to have Astrogation include timing Jumps to coincide with high tide at
> the destination but as Jump length has always been a been variable,
> I've shied away from that.  Unless you precipitate out at high tide
> (perhaps meaning pirates have more chance of an intercept?)
>
> Some implications I can think of:
> - prime departure slots on busy worlds could become very valuable
> - some (1 in 216 or perhaps 2 or 3 per standard sector) worlds will be
> a right pain to leave if you've got to wait a week till the next
> tide.  Then again, perhaps this should be made more likely as it
> increases adventure possibilities
> - there might be worlds with 'no tide' but it's a permanent 'low tide'
> - you can arrive but leaving is very risky or impossible?!
> - chandlers are going to sell up to date tide tables as I'm presuming
> there's some variation in *when* they are high/low in the local system
>
> tc
>
Collision,

I think you've covered enough for a first cut, but haven't mentioned
knock on effects too much.  Is the DM penalty reckoned to the _nearest_
high tide?  Say you have a system with jump tides at midday, 6 pm,
midnight and 6 am - is a 4 am jump at DM +2 or DM + 4?

How does this affect the _star_'s jump tides and thus masked worlds? 
Frinstance, Terra's orbit straddles Sol's 100D, with the planet masked
at austral solstice (approx 22 December), unmasked at boreal solstice
(approx 22 June).

How about multiple primaries, such as Alpha Centauri, and its stars,
Alpha Centauri A, Alpha Centauri B and Proxima Centauri? As Proxima
orbits the other two in a fairly distant orbit, how do Proxima's jump
tides interact with the bigger two?

Can tides have their base change over an astrographic region - such as
jump tides being nastier for systems either backing on to, or within, a
rift?

My wet-naval analogy here is tides/waves in the Southern Ocean - as
there's (iirc) sod all major land between 50 S and 60 S, waves can roll
around the planet unmolested and can be _nasty_ to ships they run into
(such as in the Drake Passage).

How are deep-space stations affected by jump tides, especially under my
Southern Ocean analogy?

One option is everything bobbing around like flaming corks and have jump
tides be _worse_ in deep space, on top of any existing
astrographic-region effects (such as inside a rift, or
<BeastieBoys>extragalactic</BeastieBoys>), with no significant mass to
damp them.

Another option is to equate no significant mass within substellar
distance to no _net_ tides and so deep space stations (and ships
departing a deep-space hex) effectively point and laugh at jump tides. 
Like how a tsunami isn't a major problem 200 nm offshore, but is a
doozie with one nautical mile to go.

Are there similar, if weaker, tides at 1000D limits?  (IIRC, MGT2 had
thruster plates all but crap out beyond 1000D).  How are T5's higher
order jump drives affected, if at all?

And to take it up to eleven, are black holes and other stellar remnants
under this system treated as stars of whatever mass they have? (eg an 11
stellar mass black hole is treated as an 11 stellar mass living star,
and an 0.8 stellar mass neutron star being treated as an 0.8 stellar
mass living star?)

Alex