If you are looking for a portables apps version of Celestia, I do not know of one.
If all you want is a version that runs under win10, I have one.
It is the only version of my fork that I have tested under W10.
I have one copy of W10 only, which resides in a VM with no network access.
I do this because the one time I allowed it access, it broke my lan.
So my testing was limited to 'does it launch and navigate?', which it does.
If you want to try it, is it in my downloads.
http://celestia.simulatorlabbs.com/Downloads/Capbat/look for Celestia-x86-x64.zip in that directory.
I redownloaded that exact archive, then extracted it into my W10 VM, and tested it.
It ran and navigated.
I hope that helps you.
Janus.