We have a nice private group of amateur astronomers who own and actively using 3D printers for the hobby.
Welcome to the: https://www.facebook.com/groups/345004195931930
I don't think we gonna move to the Thingiverse Groups engine though, as it seems immature technically, but considering publishing the work of our members on Thingiverse under this Group title. Hope it's not affiliated with any Astronomy Devices vendor, right?
Considering the licenses available for publishing on Thingiverse, which are very open, I don't think there's any affiliation with any vendor (though potentially, some things published here might also be available under commercial terms from other sites, if the license allows commercial use or if the original creator decides to try if can earn some money elsewhere in addition to publishing his thing here ... not everyone's a maker, after all).
So welcome, and feel free to publish here! :-) Thingiverse is quite useful as a repository for designs, even if its discussion engine is in fact a bit rudimentary ... but you can always link here from your Facebook group, for example.