Fridger,
I'm at work right now, but I'll respond in full to your message later.
Some sort of addition to the star browser would be very useful indeed and
not too difficult to implement. I have some concerns about tracking which
data is missing and which is valid--it could add a lot of complexity to
Celestia and take me quite a while to get right. I need to spend some
more time considering the implications.
--Chris
> Chris,
>
> below I attach some unanswered mail to you from almost a month ago: It
> concerned the relatively urgent assignment of default values for
> binary orbit parameters in case that the respective data were
> missing in the original catalogs. I want people to be able to notice
> that the data were missing by employing '?' in the orbit file.
>
> Also in a second mail I addressed the urgent need of a binary browser
> extension of Celestia's star browser such that people will be able to
> /locate/ those orbiting marvels into which you and others have spent
> a lot of work already ;-)
>
> Since there was no response whatsoever, my binary star efforts
> stagnated throughout the holiday season and I turned to fiddleing with
> my computers instead...
>
> Bye Fridger
>
>> Chris,
>>
>> it would be great and relatively urgent (weekend ahead!), if Celestia
>> was (trivially) adapted to assign sensible default values for /all/
>> (non-orbit related) entries in the binary orbit stc, in case a ? is
>> encountered by the parser.
>>
>> For spectral classes, it is already incorporated. In case of a ? in
>> the apparent magnitude slot, the respective star is NOT rendered at
>> all. So that's bad. Similarly in case of missing mass values, a
>> sensible default would be great. (e.g. m_A=m_B = 1 (solar mass units))
>>
>> The actual values for the defaults are not so crucial for now. It's
>> just so that I can mark clearly with a ? /all/ entries in my stc files
>> that are actually missing. At present, I have to put /concrete
>> numbers/ there and no-one can see that the respective parameter is in
>> fact /unknown/!
>>
>> A somewhat less random procedure for assigning default values would be
>> to compute and use the respective /averages/ over the catalog values...
>> Since binary catalogues are typically for certain classes of multiple
>> systems: e.g. visual, spectroscopic..., using averages over a given
>> catalog might give "guesstimate" values that are not entirely
>> nonsensical.
>>
>> Bye Fridger
>
>
>> Chris,
>>
>> ...and just in case you could find an empty coding slot ;-): it would
>> be most useful in general and especially now for /testing/ binary
>> orbits, if you could adapt the GOTO command (G key) for binaries
>> slightly as follows:
>>
>> 1) the final distance to the binary system is /computed/ from the
>> orbit size such that the components /always/ fit onto the screen!
>> (using the semi-major half axis or better of course, a more accurate
>> estimate)
>>
>> 2) the orientation matches the /viewing direction from earth/ with
>> /standardized/ orientation of north like in all (professional) orbit
>> plots for binaries, like illustrated here for dra_26:
>>
>> http://www.shatters.net/~t00fri/images/dra_26.gif
>>
>> Then (amateur) astronomers would be most happy and developers could
>> directly check the positions in Celestia against such standard
>> plots...After a glance at Celestia one then could proceed to the
>> backyard and look for that binary in the telescope ;-) ...It would
>> also be most useful to display the distance of the components in
>> arc-secs in such an earth-oriented view.
>>
>> Bye Fridger
>>
>
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