Review of extras-standard

[ajtribick]

Splitting out from #138

Looking through extras-standard:

• apollo - model created by Shrox, license situation unclear. Can't find anything on their website - the models page there only has a "coming soon" message.
• cassini - model from http://homepage.eircom.net/~jackcelestia/spacecraft_helio.htm - no license information given at that website or in the zip archives. I think this one needs to be replaced, probably with https://nasa3d.arc.nasa.gov/detail/jpl-vtad-cassini as a starting point. Unfortunately it looks like the NASA 3D archive does not have a Huygens model.
• galileo - model "based on" the one from https://nasa3d.arc.nasa.gov/detail/jpl-vtad-galileo. Should probably re-derive the cmod files/textures and replace to be on the safe side.
• hubble - according to a7424545ab9d54d7fc98cb4bc0574e82505950f4 this model is from Cham. Haven't been able to find the original. Looking at the NASA website, the only textured model has origin "DigitalSpace corporation" which has unclear licensing.
• interstellar-objects - from @SevenSpheres - could you clarify what the licensing is on this one?
• iss - this appears to be ultimately derived from an orbiter add-on from a now-offline website. From the archived copy of the website the description is as follows: "Project Alpha is a freeware addon which I created that comes default in Orbiter. Therefore I see no reason for Orbiter developers to contact me regarding the use of models and textures from Project Alpha. If you do use them please remember to mention the author of Project Alpha in the credits." - without anything more specific than that it is unclear what we can actually do here - we are NOT the Orbiter developers.
• mir - no idea where this came from, the relevant commit is 6905ce2cb481985f6c77fd182a270e9af2b99048 but has no information there.
• shroxclassic - same situation as apollo
• shroxmars - ~~same situation as apollo~~ specifically discussed at CelestiaProject/Celestia#831 as being under CC-BY-4.0.
• skylab - also a Shrox model, so same situation as apollo

Erring on the side of caution, I think we need to remove all of these add-ons, with the possible exceptions of galileo and interstellar-objects.

[SevenSpheres]

I think many of the old spacecraft models were contributed by their authors, which would imply them being released under the GPL.

The interstellar object trajectories are taken from Celestia Origin (as are most of the updated spacecraft trajectories).

[ajtribick]

Ok the models in shroxmars have been discussed and are apparently ok to distribute as CC-BY-4.0 (https://github.com/CelestiaProject/Celestia/pull/831)

The other Shrox add-ons are not discussed there and are still suspect.

[ajtribick]

Have contacted Douglas Schrock regarding their 3ds models

[DaveBowman2001]

I think this one needs to be replaced, probably with https://nasa3d.arc.nasa.gov/detail/jpl-vtad-cassini as a starting point. Unfortunately it looks like the NASA 3D archive does not have a Huygens model.

Wdym? Huygens is available on the same source link as Cassini, only attached to it

[DaveBowman2001]

iss - this appears to be ultimately derived from an orbiter add-on from a now-offline website. From the archived copy of the website the description is as follows: "Project Alpha is a freeware addon which I created that comes default in Orbiter. Therefore I see no reason for Orbiter developers to contact me regarding the use of models and textures from Project Alpha. If you do use them please remember to mention the author of Project Alpha in the credits." - without anything more specific than that it is

If I understood this correctly, we can still keep Project Alpha's ISS to the default installation of Celestia, as he did indicate to credit him as an author if someone used them (i.e. his last sentence above highlighted)

Here's a screenshot of the current ISS.ssc file as of November 2022

[DaveBowman2001]

mir - no idea where this came from, the relevant commit is 6905ce2 but has no information there.

Initially I thought this was also Bob Hundley's work due to the overall body's similarity with this image, but the commit above could possibly hint that it was made by Chris Laurel himself?