[Arcanum]

So far so good, the only thing really borked is Deneb, which is about four times further away than anything else so far.

[Iron Wolf]

wheres gamma draconis?

[Hippo]

It appears he's only showing the systems that are identifyable on a starmap.

[Polpolion]

By the way, if someone is interested, I made up a "London Underground" style nodemap on excel. File attached. IMHO it indeed clears the picture quite a bit. 

Arcanum, do you know how to convers sphere co-ordinates into cartesian co-ordinates? Because if you do, you can simply convert the locations of real stars into xyz-co-ordinates from declination, right ascension and distance. You can use equatorial co-ordinates because the distance between Sol and Earth is so small that you can approximate Sol and Earth to exist in same location.

If you don't know how, I can tell you. It's not really very complicated. In fact, since I have spare time, I tell anyway, even if you already know how to do it... Read if you want to.


Stellar locations are announced in spherical co-ordinates fixed to equator plane of Earth and Vernal Equinox (or Aries point).

Right Ascension (RA or Ra) tells us in which direction of the equatorial plane the object is. It is announced in hours, minutes and seconds, because of historical reasons as well as producing convenient calculations if local time is involved.

The right ascension zero point is fixed into Equinox; that's the point where RA co-ordinate has value 00h 00min 00.00sec. The point in the opposite direction has RA value of 12h 00min 00.00sec, and so on. To convert RA values into degrees, we define how much one hour, one minute and one second equal in degrees:

1 h = 360 degrees / 24 h = 15 degrees
1 minute = 15 degrees / 60 min = 0.25 degrees
1 second = 0.25 degrees / 60 s = 1/240 degrees

Declination (DE or Dec) announces the angle in which the star's direction elevates from equatorial plane. Declination is announced in degrees, arc minutes and arc seconds. But these minutes and seconds aren't the same minutes and seconds used in a clock... A minute in this context is 1/60 degrees, and correspondingly a second is 1/3600 degrees.


For example, Polaris has Dec value of nearly 90 degrees. An object near the equatorial plane would have Dec value of ~0 degrees. Objects on northern hemisphere of sky have positive declination, objects on southern side have negative declination.


Now that we know what RA and Dec values are and how they are used, let's take an example of how to convert RA, Dec and distance into cartesian co-ordinate values.

First of all, we point z-axis to north pole (near Polaris). X-axis we point at the Equinox point. Y axis is pointed so that it is normal to both x and z axes, and so that the co-ordinate system used is right-handed (default in modelling programs). I recommend using light years as units, they are rather convenient in this kind of task.

Okay, now how do we convert RA/Dec/Distance into convenient xyz co-ordinates?

When we have converted RA and Dec values into decimal degree values, we define the cartesian xyz co-ordinates with the help of these two angles and known distance S.

x = S * cos RA
y = S * sin RA
z = S * cos DE

Really simple, isn't it? This gives the exact co-ordinates of the star in an XYZ system used in all modelling programs, for exampl. Just throw a star object onto the program, feed in these values and the object is automatically moved into correct location.

Example.

Beta Aquilae has following co-ordinates:
Right ascension   19h 55m 18.8s
Declination   +06° 24′ 24″
Distance 44.7 light years

First we have to convert RA and Dec values into simple, decimalic degree values to more easily calculate them.

As shown before, it goes like this:

RA = 19 * 15 degrees + 55 * 0.25 degrees + 18.8/240 degrees = 285 + 13.75 + 0,07833... degrees = 298,8283 degrees = ~298,8 degrees
Dec = 6 degrees + 24/60 degrees + 24/3600 degrees = 6,4067 degrees = ~6,4 degrees

x = S * cos RA = 44.7 ly * cos 298,8 deg = ~ 21.53 ly
y = S * sin RA = 44.7 ly * sin 298,8 deg = ~ -39,17 ly (note the negative value, it is important to remember to put it in...)
z = S * sin DE = 44.7 ly * sin 6.4 deg = ~ 4,98 ly

x = 21.53
y = -39,17
z = 4,98

These are the co-ordinates of Beta Aquilae. Convert all the other existing star co-ordinates in similar fashion and you get an accurate model of relative locations of stars.

 

Wow! That's a lot of math...

I saw some triganomic ratio stuff in there, but I have no idea what you were doing with it, and I don't feel like actually reading the post.

[Arcanum]

No, I'm only showing the stars I've plotted so far.  8)
To my knowledge, the only FS star system that doesn't exist in the real world is Vasuda.  (Overlooking the fact that  star systems are substantially different in-game from what we already know about those stars.  For example, in reality Capella is a four-star system, one pair yellow giants and one pair of red dwarfs.)

[Herra Tohtori]

It appears he's only showing the systems that are identifyable on a starmap.

What do you mean?

Gamma Draconis is a real star and very much identifiable on a star map. It's the brightest star of the constellation Draco. Its co-ordinates are:

RA 17h 56m 36.4s
Dec. +51° 29' 20.3''
Distance 148 ly

That would place it about... Almost same direction as Vega, less than ten degrees northeast (or "up" and "right") from it (viewed from Earth), but it's six times further into space.


There are, however, fictional systems in FS2. Here's a list of them:

Vasuda
Laramis
Ikeya (there's many comets partially named by astronomer Ikeya, and one asteroid, but no star or star system.
Shivan Nebula (although there have been propositions about which nebula it could be, most notable candidates being Lupus Nebula [SN1006 Supernova remnant] and Crab Nebula [SN 1054 Supernova remnant], although it could be some other place altogether.)
Binary System beyond said nebula - even less clues as to whereever this may be.


I don't recall any other fictional canon systems. Others should be based on real life counterparts.

Then there are multiple non-canon worlds that aren't real star systems:

Delphi
Tau Sigma (I've always wondered if this was actually supposed to be TAu Ceti, which would've been a real star...)
Tanis Australis
Gehenna Cygni (although if the spelling is b0rked.. Gamma Cygni would be a real star.)
Transcend's dark nebula

Then there are many uncharted systems seen in passing during some of the "Escape Enemy through multiple jump corridors" campaign...


@thesizzler: 

It's a simple co-ordinate transformation from sphere co-ordinates used in astronomy, into cartesian (XYZ) co-ordinates used in modelling programs. Its almost simplest possible example of space vector calculations, and it really isn't as intimidating as someone might think.

It's not really that much math, I just felt like explaining how the co-ordinates are converted first into degrees, then into X-Y-Z values.

Feel free to disregard that post, though. 

EDIT: Moved Laramis to correct group...

[Mefustae]

No, I'm only showing the stars I've plotted so far.  8)
To my knowledge, the only FS star system that doesn't exist in the real world is Vasuda.

I think we have an identity for that star, if i'm not mistaken.

[Herra Tohtori]

No, I'm only showing the stars I've plotted so far.  8)
To my knowledge, the only FS star system that doesn't exist in the real world is Vasuda.

I think we have an identity for that star, if i'm not mistaken.

You are mistaken.

There's not much canon information about Vasuda, except that the system's planets (or at least Vasuda Prime) were pwned by SSD Lucifer.

[Axem]

Then there are multiple non-canon worlds that aren't real star systems:

Laramis
Delphi
Tau Sigma (I've always wondered if this was actually supposed to be TAu Ceti, which would've been a real star...)
Tanis Australis
Gehenna Cygni (although if the spelling is b0rked.. Gamma Cygni would be a real star.)
Transcend's dark nebula

Laramis is non-canon?

[Herra Tohtori]

No it isn't. I'm too tired.

It's supposed to be on the upper group of fictional systems along with Vasuda, Ikeya, Shivan Nebula and Binary System. Thanks for pointing it out.

[Dark Hunter]

Then there are multiple non-canon worlds that aren't real star systems:

Laramis
Delphi
Tau Sigma (I've always wondered if this was actually supposed to be TAu Ceti, which would've been a real star...)
Tanis Australis
Gehenna Cygni (although if the spelling is b0rked.. Gamma Cygni would be a real star.)
Transcend's dark nebula

Plus 90% of the star systems in ITDOH. 

[Goober5000]

You misspelled Tania Australis and Gienah Cygni, which are real stars.

Assume Tau Sigma is Tau Ceti, and Vasuda is Beta Hydrii (informal forum consensus), and see what those look like.  Also, it would be cool if you could put both the Lupus and Crab Nebulas on the map, with lines to each.

[Iron Wolf]

You misspelled Tania Australis and Gienah Cygni, which are real stars.

Assume Tau Sigma is Tau Ceti, and Vasuda is Beta Hydrii (informal forum consensus), and see what those look like.  Also, it would be cool if you could put both the Lupus and Crab Nebulas on the map, with lines to each.

Those are the frontrunners for what the Nebula beyond gamma draconis is thought to be, right?

[Flipside]

I'm wondering if Sigma Ceti isn't a hypothetical Binary partner of one of the larger stars in Cetus to be honest, we already have Beta Ceti, which is one Deneb (Alpha Sygni is another), and a couple of Giant class stars, considering that Tau Ceti is a metal-poor star and therefore unlikely to have inhabitable planets.

[Goober5000]

Those are the frontrunners for what the Nebula beyond gamma draconis is thought to be, right?

Yes.  I was responding to Herra Tohtori's post above:

Shivan Nebula (although there have been propositions about which nebula it could be, most notable candidates being Lupus Nebula [SN1006 Supernova remnant] and Crab Nebula [SN 1054 Supernova remnant], although it could be some other place altogether.)

[Herra Tohtori]

I'm wondering if Sigma Ceti isn't a hypothetical Binary partner of one of the larger stars in Cetus to be honest, we already have Beta Ceti, which is one Deneb (Alpha Sygni is another), and a couple of Giant class stars, considering that Tau Ceti is a metal-poor star and therefore unlikely to have inhabitable planets.

Errr...

Deneb is Alpha Cygni, not Alpha Ceti, and Beta Cygni is a different star altogether... But Beta Cygni itself is a threefold binary star, consisting of brighter and dimmer component at long distance from each other, and the brighter component itself is a close binary system.

Cygni is the genetive form of Cygnus (aka Swan, constellation), whereas Ceti is corresponding form of Cetus (Whale).

Tau Sigma, while sounding cool, is pseudo-astronomian name for a star, since the Greek letters are used (usually) to indicate the brightness of the star in certain constellation, viewed from Earth. So the brightest star of constellation of Centaurus has the name "Alpha Centauri"... second brightest star in Cygnus is called Beta Cygni and so forth.

However, there are a few inconsistensies to this naming scheme... for example, Gamma Draconis is not the third brightest star of Draco, but instead it is the brightest. This is most likely just a confusion from older ages, since Alpha Draconis (Thuban) used to be the pole star (at times around 4000-2000 BC) and was most likely named Alpha Draconis because of this ancient importance as well as its traditional Arabic name Thuban, which is the same name as the name of the constellation in Arabic (Thuban = Basilisk or Dragon). But I digress...

So, Tau Sigma can not be a proper star designation since there is no constellation Sigma. Furthermore, there is no star called Sigma Ceti appearing in either canon or non-canon Freespace 2.

Perhaps we should ask Blaise, what system Tau Sigma is supposed to be. Tau Ceti could be one possibility, but as you said, TAu Ceti is a metal-poor system and I don't really see any real point in keeping mining colonies on a metal-poor area of space. Unless they are mining for example tritium from comets or the like... Obviously it could simply be called Tau Sigma with no connection to any real star whatsoever. Over-analyzing is a common mistake in this kind of threads.

[Flipside]

Actually, I was almost right with Beta Ceti, it's common name is Deneb Kaitos..

http://en.wikipedia.org/wiki/Beta_Ceti

As for the other part, yeah, I was tired and remembered to check for spelling, forgot to check for sense.

[Goober5000]

Perhaps we should ask Blaise, what system Tau Sigma is supposed to be.

Careful, Blaise Russel didn't create Derelict.  He did the remake, but the original was made by Agatheron and Kellan.

I think the only people who might know would be the Derelict/Warzone/BWO old guard, such as Ace and IceFire.

[Arcanum]

added:  Gamma Draconis, Crab Nebula, Vasuda/Beta Hydri, Adhara (Epsilon Canis Majoris), Procyon

I haven't figured out how to create a cylinder between two points in the program I'm using, so the node lines are being a bit irritating to make.  Also I reluctantly decided to quarter Deneb's distance; it's still a tad further away than anything else so far, but it's a little easier to work with now.





One note on the nebula:  after some research, I decided that the Crab Nebula was more plausible than the Lupus Nebula.
   The two nebulas are results of two distinct mechanisms.  SN1006 (Lupus) is believed to have been a type Ia supernova, since the nebula does not contain a neutron star/pulsar or such, and because ancient astronomers described it as appearing, dimming, then increasing intensity again.  These kinds of supernovae are only created by white dwarfs (old stars) which have come too close to a particular critical mass.  SN1054 (Crab), was the result of a core-collapse supernova, characteristic of massive stars.  However, there's an interesting twist:

"Theoretical models of supernova explosions suggest that the star that exploded to produce the Crab Nebula must have had a mass of between 8 and 12 solar masses. Stars with masses lower than 8 solar masses are thought to be too small to produce supernova explosions, and end their lives by producing a planetary nebula instead, while a star heavier than 12 solar masses would have produced a nebula with a different chemical composition to that observed in the Crab.

A significant problem in studies of the Crab Nebula is that the combined mass of the nebula and the pulsar add up to considerably less than the predicted mass of the progenitor star, and the question of where the 'missing mass' is remains unresolved."
http://en.wikipedia.org/wiki/Crab_Nebula

...which is exactly what you would expect if a supernova was artificially triggered!  Capella A is only 2.7 solar masses.

[Goober5000]

That's going in the wiki.