So the site looks a little overloaded, but it's amazing when you get the data downloaded. If you have a very fast gfx card do try the FIRE galaxies viz.
The Gaia data viz is also impressive. I've been waiting to work with this data for awhile.. this will make it much easier. Thanks to the authors!
A small nity-picky: From academic point of view if I was a reviewer I would point out that the Potree project is prior art in rendering points in browser, considering Octree based spatial distribution of points for rendering of arbitrarily large data sets.
Potree is designed mainly for pointclouds of terran objects while this is obvioulsy intended for astronomic datasets so the domain is a bit different.
https://www.alexbgurvi.ch/Firefly/website/_site/index.html