Starry sky mod ?

[luxorion]

Hi,

During night flights I have noted that stars of various magnitudes appears in the sky.
But as fan of astronomy, I quickly noted that I recognized no constellations, not even the Big Dipper…

However I see that stars are not simple dots placed randomly here and there; they follow the airplane and their pattern seems to remain from one session to another (to confirm with the programmer).

We do not need many stars, a hundred could be enough as we only need the main stars of constellations (say maximum up to 10 stars per constellation) e.g. up to magnitude 4 or so if it is a huge work.

I have no idea of how this could be achieved.

Question : Is there somewhere a “skymap” that we can add to BMS to add more realism or someone able to create it ?

Thanks in advance.

[Polak]

Hi,
Search the forum with keyword “star”. It should bring you some threads, which could help you navigate through this subject.
Star.dat file is very simple and editable with 1347 entries. You may view it in Hex Editor set to 36 char in row. First 2 values are position coordinates (maybe a dword or maybe a float), last magnitude (integer and that I know because once I managed to change that with visible result). Make first backup of the file take a look and good luck.

[luxorion]

Hi,
My hexa editor cannot display data in clear. See below

I could complete it with real coordinate if I have the right editor and how to encode these data but I need help.
Thanks

[Polak]

Change in Tools->Options->Appearance to 36 char per column.

[luxorion]

Sorry but it does not help. It is in clear

[Polak]

Sorry but it does not help. It is in clear

You mean unclear, right? If so, it is time for detective work in what format are the coordinates and what model of skybox was used. I am rather positive that the last value (column to the right is the magnitude/brightness of the stars represented by integer 0-255). For the test you can change all of them to 255 and see that each star would have the same max brightness.

[luxorion]

Unclear, yes.
But your suggestion to work as a detective is not easy.
I 'ld like to encode stars in clear text, then to the program to convert data in the right format to create the .dat file.
As no such a tool seems available or not enough simple to use for an amateur like me, I cannot go further…. I don’t speak hexa.
It’s pity.

But if someone is willing to do that and update the star.dat, I can provide him coordinates and magnitudes of stars (data that are probably easy to find on the web in a catalog of brightest stars).
The objective being to display stars on screen at their “real” relative position in the sky, not randomly of course.

Thanks for your help.

[OldGoat5]

I actually was thinking of this earlier today. If you post/find the coordinates and the relative magnitudes for use in bms I can attempt to whip up some kind of program/whatever that could update the .dat. If you can end up writing the coordinates etc in a simple text file that would theoretically make it easier to program. You can write the names of stars and the data or anything, the format does not matter. I suppose they should be the coordinates as seen from Seoul’s latitude as a basis, then maybe the same could be done for other theaters.

[Arty]

well welcome to the falcon mod - developing world where nothing is easy.
U have to use the force… Is the force strong in u…? ohh to old he is to learn… ohhh no pattion he has… ohhh yes the force is strong in him… hehehe

[Arty]

if those are coords it would be easier for monster to put them inside Terrain Editor. And as Polak says the last ones are the magnitute of the star (not sure as I see many on the same value) then he can help on the star system…

[luxorion]

@OldGoat5:

I actually was thinking of this earlier today. If you post/find the coordinates and the relative magnitudes for use in bms I can attempt to whip up some kind of program/whatever that could update the .dat……

OK. I can do it.
It is without guarantee because I have to investigate but I think that I could provide you a txt file listing equatorial (RA and decl) coordinates and visual magnitudes of bright stars if these sole data are enough.
I know that the Yale Bright Star catalog includes over 9000 stars. It is already a serious base.
See at http://tdc-www.harvard.edu/catalogs/bsc5.html
We can also get one from VizieR
http://vizier.u-strasbg.fr/viz-bin/VizieR-3?-source=V/50/catalog
I have to check what are those 1347 existing, knowing that the limit magnitude will be 4 or 5 maximum.
Maybe that coordinates in decimal could also be useful (e.g. 11.5 instead of 11h30’00")
Give me some time but I follow this thread.

[Aragorn]

Upon release, Falcon4.0 actually boasted that one could “navigate by the stars”.

Just a little tidbit of F4.0 trivia…

[luxorion]

Here is a raw file in CSV format (size 504 KB) and sorted by visual magnitude (brightest first)
Right-Clic on the link to download it :
http://www.astrosurf.com/luxorion/Documents/stars-catalog-vizier-forBMS.csv

I have already performed some changes and added the color of stars.

There are 5024 entries or stars listed up to magnitude 6.0, the limit naked eye.

There are 1500 stars until magnitude 5. I think that it is enough for BMS if currently it uses less than 1400 stars.

[Polak]

Before jumping to perhaps hasty correction of old star.dat file, can anyone perhaps authoritatively and without any doubt confirm, that the positions of the stars in Falcon aren’t by chance according to true RL constellations.
It is possible that positions of the stars on the Falcon firmament are absolute and not centered on Seoul and rather other part of the globe (Greenwich and Equator maybe?)
also….
All this should be verified perhaps with star.dat and in conjunction with file weather.xxx, which clearly reads proper timezone and absolute latitude and longitude for the theater.
Here is one for Korea:

TimeZone 9
Latitude 37
Longitude 126

[Arty]

luxorion the magnitude ain’t affected by the atmosphere? so when u r at 30000ft I believe their brightness is larger… as less atmosphere in the way…

Also 1400 stars for which area? Don’t forget those have to be done per theater… meaning right now if u fly balcans or aegean u see what Korean ppl r seeing…

[Polak]

Don’t forget those have to be done per theater… meaning right now if u fly balcans or aegean u see what Korean ppl r seeing…

@Arty,
You seem to be not quite listening… Not that what has been said above been fully verified, but it maybe makes some sense … or does not?
There is a way to dig to the bottom of that. Make a star.dat with one star only and then you can confirm how it is all made.

[Agave_Blue]

@Arty:

luxorion the magnitude ain’t affected by the atmosphere? so when u r at 30000ft I believe their brightness is larger… as less atmosphere in the way…

Also 1400 stars for which area? Don’t forget those have to be done per theater… meaning right now if u fly balcans or aegean u see what Korean ppl r seeing…

I thought:

Determination of a stars magnitude (in a star map/catalog, for instance) was an absolute measure. I.e., normalized for all stars. If so, atmospheric changes affect all stars the same. So once the magnitude is set, it’s BMS ‘magic’ that changes apparent brightness with atlitude and should do so proportionally for all stars. ??

And, all stars in the Northern Hemisphere (i.e. - the current Falcon world) are the same …. on any given night, Koreans see the same stars as Greeks … ;). ??

[luxorion]

Agree with Polak.
Magnitude is an absolute data but of course its value depends of extinction and external events (time of the day, atmosphere tickness, pollution, etc).
We could also take into account the atmospheric refraction but it of 1 arcmin max. at 45° of elevation.
So in BMS we can ignore these parameters and only take into account the theatre latitude and the time of the day.

I updated the CSV at 15:10 GMT with decimal values and additional names (could be useful as BMS display labels).

[OldGoat5]

I got a 404 error when trying to download the xls.

[luxorion]

You probably tried during an update. It is Ok now. The CSV is enough for BMS
http://www.astrosurf.com/luxorion/Documents/stars-catalog-vizier-forBMS.csv