Using blender to make a real life celestial globe.

I’m using blender in a pretty creative way, but I need a bit of help. I’m also kind of using the application “backwards” from it’s typical use.

I decided to try and make a real-life celestial globe, like the ones in the 1600s with the really artistic figures painted over the constellations. One of the problems with the old globes is that there has been some advancement in astronomy since then. When overlaying the gores on a sphere nowadays the stars are not in the most accurate of places. This has to do with manual eye-sighting, orbital precession, and working with 30 degree orange slices on flat paper using compasses and squares.

I decided to download a star catalog from Yale and with some clever polar translations, was able to create a mapping of all the stars magnitude 5.3 and below. I projected these onto a sphere shape in Blender using a python script, which I will get into a bit.

The idea is I want to be able to render out just the wireframe in 15º by 15º squares. This will allow me to lie down the art for each constellation flat and then put together the globe. I’m not using gores, but each constellation will be a “puzzle piece” of the globe and be put together that way.

I understand that as I approach the poles, there will be overlap, that’s fine. The idea is to get a mosaic I can then shape in Photoshop and print out my final “puzzle piece” for the globe.

Here are two Issues I have:

  1. When I import stars from my CSV file, it’s creating a new object for every star. Things start to chug when it gets to 4000 stars or so. I usually stop the import and join all the icospheres created as a single object and it’s fine. I wonder if there is a way to create everything as one object… It’s not a big thing as I don’t have to do the whole sky at a time. I can split the CSV up by magnitude.

  2. I’m not too sure how to render just the wireframe. When I try and do a UV unwrap -> project from view I get a mess. Doing a “proper render” renders out everything, including my reference sphere as solid… in this case black as I have no lights.

I attached a picture of what I kind of have so far, (along with a picture of Orion). The script is there too. It’s messy and has things included I don’t use. (Oh and BTW how to I delete old pictures I have posted here. I’d much rather not have some on the server I posed on accident)

As an aside. I’m also looking for the camera zoom so I can narrow my view a bit, it’s a bit too wide

thanks for the help.

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I think I can help you with #2. I made a video because writing step by step instructions would just be confusing and tedious.

Hope that helps!