Ideas for honorverse space navy improvements?

On Tue, 1 Jan 2008 17:05:47 -0800 (PST), Ben H
<cataphractlance DeleteThis @gmail.com> wrote:

>I don't rightly understand what you're getting at.
>If I found myself in a foreign star system, and was able to correctly
>identify the stars Betelgeuse, Rigel and Aldebaaran, what good does
>that do me?
>I can't triangulate my position until I know where I am in relation to
>the stars, which requires knowing the distances. Measuring the
>distance to a star like Rigel would require the use of parallax, which
>takes longer then scanning the stars, saying Ope! There's Rigel! A
>starship does have the advantage of being able to cross a large volume
>of space very quickly, which would help refine parallax measurements
>more quickly, but you're still going to want to jump at least 1 AU
>from your initial point before taking a second measurement. It is
>_not_ something that can be done to any useful degree of accuracy in
>seconds, or even minutes.
>_If_ you could locate enough Cepheid variables, with a short period
>mind, you could do it in a couple hours, most likely.

You don't need the distances.

Take a piece of paper, put four dots on it.

3 dots represent stars, 1 dot is your location.

Draw three lines from your dot through the three star dots and off to
the edge.

Photocopy your paper and cut away as much of the copy as you can while
keeping the lines. (Heavy paper will help here.)

Try to arrange the copy such that the lines cross the star
dots--you'll find there is exactly one position where this will work
unless you ended up with a symetric pattern.

Note that you used no means of measuring the lines to do this, all
that matters is the angles.

Since we are trying to place our location in 3 dimensions instead of
two we need to add another star. Thus 4 stars will do it. *ANY* 4
identifiable stars.
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In article <01c84d34$34af4900$LocalHost@default>,
"Michael R N Dolbear" <me DeleteThis @privacy.net> wrote:

> Aahz Maruch <aahz DeleteThis @pobox.com> wrote
>
> > Ben H <cataphractlance DeleteThis @gmail.com> wrote:
>
> > >I'm just an amateur astronomer, so there might be better informed
> > >heads in these lofty circles, but analyzing just the brightest
> > >_hundred_ stars shouldn't be difficult, or time consuming at all.
> The
> > >warships after all carry optics capable of picking up a mere
> spaceship
> > >at considerable ranges, running a spectrogram on a particularly
> bright
> > >star should be easy.
> >
> > There's also the issue that because you don't know where you are, you
> > have no clue what your vector is and therefore you don't know what
> > red/blue shift to apply to each spectrogram.
>
> For the _Harvest Joy_ problem, the hundred brightest stars are not what
> you want to start with since they will be brightest because they are
> closest ("local dazzle"). Nor do you care about distances yet, just
> angles for triangulation.

First of all, they'll probably have the spectra of those local stars in
their database. A database with the spectral fingerprints of a million
stars can fit on a USB thumb drive now.

Even if they don't have every star in their database, of the top 20
brightest stars in the sky (other than the sun) 7 are more than 300
light years away:

Rank Name Distance
2 Canopus 310
6 Rigel 770
9 Betelgeuse 430
10 Hadar 530
16 Antares 600
19 Deneb 3200
20 Mimosa 350

That means that they're still going to be among the brightest stars in
the sky, no matter where you go in the settled portion of the
Honorverse. Odds are that about half of them will be even brighter than
they appear from Earth. (You have to go a *really* long way for Deneb
to stop being one of the brightest things in your sky.)

>
> Thus locate a set of galaxies like Andromeda and/or pulsars and check
> them in the catalogue. The angles will give you a starting position in
> our galaxy and their spectra red shifts compared with catalogue your
> current vector velocity.
>
> You then repeat selecting a set of intrinsically bright stars based on
> your estimated position and finally calculate what stars should be the
> "hundred brightest" *here* and compare with the actuals. Problems will
> include variable stars, flare stars, stars that have gone nova but no
> one has updated the catalog yet, dim stars that are close to you but
> are so dim as to be missing from the catalogue etc etc.
>
> Time taken for the last stage would depend on how such many problems
> needed a manual check, for the first stage on how many parallel
> channels can work on the "find a galaxy" survey.
>
> Actually _Harvest Joy_ had two problems, The first was "where are we
> galactically", answer 4 lightyears from Lynx, direction vector such and
> such.
>
> The second was to locate the local terminus wormhole accurately enough
> to be able to return. The accuracy needed for that, especially in a
> planetless system, is probably beyond us today (I assume the terminus
> is bound in some way to the nearest star).
>
> Note that ordinary inerstellar navigation doesn't need either of these
> techniques; a ship drops out at the hyper limit, checks the brightness
> and doppler shift of the really bright stars that show a disc then sets
> a course for the planet and a terminus has beacons.

--
Quando omni flunkus moritati
Visit the Buffy Body Count at <http://homepage.mac.com/dsample/>
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In article <gk3nn35meddlt22ekfbslpd8t4nhkgj1kf RemoveThis @4ax.com>,
Dahak <Dahak_II RemoveThis @theXOUTfifthimperium.com.invalid> wrote:

> On 2 Jan 2008 12:08:56 GMT, an orbiting mind-control laser made
> "Michael R N Dolbear" <me RemoveThis @privacy.net> write:
>
> >Has MIRV appeared other than in infodumps ?
>
> It may have been alluded to once or twice, but I can't recall
> where. At the moment, I'd have to say no.
>
> >I have always assumed that the missile goes ballistic, the wedge is
> >dropped, and then the MIRVs separate, optimise their positions, and
> >agree to go bang ("agree" so as to avoid fratricide). It may also be
> >possible to cease to accelerate but postpone dropping the wedge thus
> >giving a little more protection from laser point defense.
>
> But going ballistic at those ranges is suicide.
>
> And even if they could keep the wedge up at zero accel (unlikely
> as that would be 'varying the accel of a running missile,' explicitly
> rejected by Himself.), at that point, the wide-open throat would be
> bearing on all those lovely point-defense clusters.

Why does the throat have to be pointing at the target? What's to keep
them from turning side on to it? (And how fast does the wedge go away
if you destroy the hardware creating it? Can you have your warhead
detonate, and fire its lasers through where the missile's wedge was a
microsecond ago?)

--
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Visit the Buffy Body Count at <http://homepage.mac.com/dsample/>
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Dahak <Dahak_II.DeleteThis@theXOUTfifthimperium.com.invalid> wrote

> "Michael R N Dolbear" <me.DeleteThis@privacy.net> ecrited:
> >I have always assumed that the missile goes ballistic, the wedge is
> >dropped, and then the MIRVs separate, optimise their positions, and
> >agree to go bang ("agree" so as to avoid fratricide). It may also be
> >possible to cease to accelerate but postpone dropping the wedge thus
> >giving a little more protection from laser point defense.
>
> But going ballistic at those ranges is suicide.

I don't think so.

If the missile is heading towards a ship then the bow aspect of the
wedge is open anyway to point defense lasers so no great loss if the
wedge goes down. Same or an improvement, I think, for a counter-missile
hit since the missile with no wedge presents a smaller effective target
than for a wedge to wedge "collision". Losing the wedge may mean there
is a loss of protection if the missile is trying for a bow or stern
aspect shot however but only for the few seconds which the MIRV cluster
needs for its decision process.


> And even if they could keep the wedge up at zero accel (unlikely
> as that would be 'varying the accel of a running missile,' explicitly
> rejected by Himself.), at that point, the wide-open throat would be
> bearing on all those lovely point-defense clusters.

Zero accel may be a special case.

If the missile is attempting a sidewall shot the throat has been wide
open to point defense all along unless someone set it for evasive
routing so until the last moment the point-defense lases are masked by
the roof or belly of the wedge of the ship they are firing from.

--
Mike D
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Dahak <Dahak_II.DeleteThis@theXOUTfifthimperium.com.invalid> wrote
> "Michael R N Dolbear" smurfed
> >Dahak <Dahak_II.DeleteThis@theXOUTfifthimperium.com.invalid> wrote
> >
> >> There is /also/ a minimum delay between the time you hit the
> >> button to start your boost into hyper and when the field builds
high
> >> enough to actually translate.
> >
> >Textev ? Infodump ?
> >
> >The sole account of a junction transit that mentions "Hyperspace
now!"
> >doesn't have any apparent delay.
> >
> >SoSag has "There was a safety margin of almost fifteen seconds on
> >either side of the critical threshold" ?
>
> There was a posting by DW to the Bar detailing hyper generators in
> relation to Chin's failure to escape into hyper at the end of /At All
> Costs./
>
> Oddly, I don't see it on the Infodump.
>
> I'll add it tonight.
>
> And, now that I think about it, it does tend to conflict with the
> bits regarding Junction Transits.

Yep.

[HaE ch 9]

"Stand by for hyper," she said. Then - "Hyper now!"

> Another example of a laggardly boost into hyper would be
> Darlington's attack on the Basilisk Terminus.

[SoSag ch 18]
Unless the ship was sitting there with both its impeller nodes and its
hyper generator carrying full loads--not a good idea for civilian-grade
components--it was going to take a minimum of half an hour, by any
realistic estimate, for the crew to fire up and make their escape. If
Bogey Three's impeller nodes were hot[...] And bringing her hyper
generator on-line in a cold start would require an absolute minimum of
thirty minutes. ==

--
Mike D
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On Wed, 02 Jan 2008 18:23:34 -0500, an orbiting mind-control laser
made Don Sample <dsample RemoveThis @synapse.net> write:

>Why does the throat have to be pointing at the target? What's to keep
>them from turning side on to it? (And how fast does the wedge go away
>if you destroy the hardware creating it? Can you have your warhead
>detonate, and fire its lasers through where the missile's wedge was a
>microsecond ago?)

Probably because that's what David's been saying about these
things from Day One.



http://infodump.thefifthimperium.com/Harrington/hh_shipkiller_missile_...sion.ht


http://infodump.thefifthimperium.com/Harrington/hh_missile_orientation.htm


-JPB
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On Dec 31 2007, 8:09 am, Lorenzo Micheletto
<lorenzomichele....RemoveThis@libero.it> wrote:
> troy.te....RemoveThis@gmail.com wrote:

>
> a) "Hyper submarines"
>

Ships that skip that traverse the hyperspace boundary lose over ninety
(96?) percent of their velocity. This is why there is a diminishing
return to going up a level to fly faster-- the higher cruising
velocity is pointless if you spend too much time accelerating to get
up to it. For a hyper sub, its fire control has to handle stupid
amounts of target relative motion, as it will be very nearly zero
after it comes back to normal space (two translations will leave it
with less than one percent of its initial velocity). Given that the
loss of velocity may be more than the distance contraction for the
first layer of hyperspace, the hypersub cannot intercept anyone that
wasn't going to come within range, anyways.
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On 2 Jan 2008 23:04:46 GMT, an orbiting mind-control laser made
"Michael R N Dolbear" <me.TakeThisOut@privacy.net> write:

>> And, now that I think about it, it does tend to conflict with the
>> bits regarding Junction Transits.
>
>Yep.
>
>[HaE ch 9]
>
>"Stand by for hyper," she said. Then - "Hyper now!"

Of course... David can probably wiggle out of this by saying that
"Well, they know the mass of the ship and how long it takes to build
up the translation field with their generator, so the time at which
they say 'hyper now!' is really the amount of time their known field
takes to build-up /before/ they have to physically translate."


Yeah... I could see him using that argument, but it'll be a while
before I can get hold of the guy to try an pin him down for a reply.


-JPB
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In article <477c259c$0$16165$c3e8da3@news.astraweb.com>,
Loren Pechtel <lorenpechtel DeleteThis @hotmail.invalid.com> wrote:

> On Tue, 01 Jan 2008 20:33:29 -0500, Don Sample <dsample DeleteThis @synapse.net>
> wrote:
>
> >You could make a widget now that could do the job in seconds. You don't
> >have to look at individual stars, one by one. One digital photograph of
> >the whole sky to locate and take the spectra of every star, and then a
> >little data crunching by a computer to compare them against a database
> >of stellar spectra.
>
> I don't think this would give very good accuracy--all your data points
> will be in a fairly narrow arc. I would mount a few cameras on the
> ship to give a wider field of view.

Use a fisheye lens.

Granted that with current tech, the accuracy wouldn't be that great. A
20 megapixel CCD would give you a location accuracy of about 5 light
hours from a single image, but by Honor's time they'll have much more
sensitive detectors. (Holographic imagery requires *lots* of pixels.)

--
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Visit the Buffy Body Count at <http://homepage.mac.com/dsample/>
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On Jan 1, 12:49 pm, Brian McDonald <Brian_knowspam.McDon... RemoveThis @shaw.ca>
wrote:
> On Tue, 01 Jan 2008 14:02:35 -0500, Don Sample <dsam... RemoveThis @synapse.net>
> wrote:
>
> >> At detonation ranges, any missiles with a decent chance of hitting
> >> the target are no longer actually maneuvering defensively: they're
> >> busy settling into a direct approach so that they can sight their
> >> target, which simplifies the PD firing solution immensely - there's
> >> little to no bearing change.
>
> >Even if it can't change its vector by much, just cutting the drive at
> >some point during that 1/10 of a second makes it a pretty much
> >impossible targeting problem.
>
> >And a tenth of a second is a very long time, even for current computers.
> >The missile can make a random vector change, and then spend the next
> >.099999 seconds finding its target, aiming at it and then detonating.
>
> ok think i got what was bothering me. bomb pumped xray lasers depend
> on those laser tubes to generate their beams of doom. from what i've
> read those things need to be perfectly aligned to work right and by
> perfectly i mean within very very tiny tolerances. seems to me that
> building something like that to withstand high speed maneuvering is
> going to be somewhere between incredibly difficult and just plain
> impossible. i don't think they can really do any terminal maneuvering
> without rendering themselves largely ineffective as weapon over this.


They are only really finicky if they have propogate an x-ray laser
beam while supporting a load of many tens of thousands of newtons.
The US abandoned bomb pumped lasers primarily because they were not as
powerful as Teller claimed they would be. The tricky bit with x-ray
lasers is targetting. A conventional laser is its own tracking system
(watch the glowing dot on the target), but x-ray laser optics are
opaque and the beams do not quite propogate at the same velocity
(c=sqrt[group velocity * phase velocity] and both velocities vary with
index of refraction and frequency) as useful targeting frequencies
(The problems are even worse for grasers). For a missile, you need to
be able to rigidly point the rod array at the target. What probably
works is to set the shot pattern at the factory and pot the entire rod
array in a rigid material that is nonconducting and transparent to x-
rays. That way the rods are much less wobbly than whatever orients
the warhead. The warhead is not so much trained onto the target as
set spinning in such a way as the target is in front when the bomb
excites the laser.
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On Jan 1, 7:31 pm, Don Sample <dsam... RemoveThis @synapse.net> wrote:
> In article <actln3t7g5n7tkp1qdmkcp5sl4s7r5l... RemoveThis @4ax.com>,
>
> Dahak <Dahak... RemoveThis @theXOUTfifthimperium.com.invalid> wrote:
> > On Tue, 01 Jan 2008 20:49:49 -0500, an orbiting mind-control laser
> > made Don Sample <dsam... RemoveThis @synapse.net> write:
>
> > >Using existing real world technology you could build a digital camera
> > >that would take the spectra of every star in the sky in under a second.
>
> > I would find that difficult to believe for a random starfield.
>
> > -JPB
>
> It doesn't matter how random the star field. One photograph gives you
> the position and spectrum of every star in it.
>
> --
> Quando omni flunkus moritati
> Visit the Buffy Body Count at <http://homepage.mac.com/dsample/>


How do you get position and spectrum in one image? To get a spectrum
you have to generate a smear for each star long enough that the
spectral lines that you are looking for are at least one pixel wide.
To get that in one image, no two stellar spectra can overlap. This
implies that either the field of view is uselessly small, or the
camera is huge.
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On Wed, 02 Jan 2008 20:01:20 -0500, Don Sample <dsample.RemoveThis@synapse.net>
wrote:

>In article <477c259c$0$16165$c3e8da3@news.astraweb.com>,
> Loren Pechtel <lorenpechtel.RemoveThis@hotmail.invalid.com> wrote:
>
>> On Tue, 01 Jan 2008 20:33:29 -0500, Don Sample <dsample.RemoveThis@synapse.net>
>> wrote:
>>
>> >You could make a widget now that could do the job in seconds. You don't
>> >have to look at individual stars, one by one. One digital photograph of
>> >the whole sky to locate and take the spectra of every star, and then a
>> >little data crunching by a computer to compare them against a database
>> >of stellar spectra.
>>
>> I don't think this would give very good accuracy--all your data points
>> will be in a fairly narrow arc. I would mount a few cameras on the
>> ship to give a wider field of view.
>
>Use a fisheye lens.
>
>Granted that with current tech, the accuracy wouldn't be that great. A
>20 megapixel CCD would give you a location accuracy of about 5 light
>hours from a single image, but by Honor's time they'll have much more
>sensitive detectors. (Holographic imagery requires *lots* of pixels.)

5 light hours! Wow! That is *FAR* better than I would have thought
you could get from such data.
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