Show HN: Galaxium, an experimental WebGPU space explorer
galaxium.app100 points by guillaumec 5 days ago
100 points by guillaumec 5 days ago
Hello, I am the creator and maintainer of Stellarium Mobile. I have been working in my free time for about a year on this new project Galaxium, that is more about traveling in the universe rather than looking at the sky from Earth. It is still experimental, and at the moment I am not sure what it will become. Feedback is welcome.
It feels like an improved version of Celestia on the web, which I've wanted for a long time. The rendering is awesome!
I like the motion blur on the stars, but it increases the brightness of each star. It would look more consistent if the brightness of a star was constant regardless of motion. I guess the brightness increase makes things look cooler when you're warping through space but it's distracting when orbiting the camera around objects.
I think clicking to select things could be improved. Clicking on names is reliable but clicking on rendered objects seems unreliable. Sometimes clicking on a planet or star does nothing. Also my mousewheel seems quite slow to zoom, I know this is hard to tune across platforms on the web, I'm on Ubuntu 26 currently.
I can think of about a billion features to add. Real time clouds for Earth, a bunch more satellites and spacecraft, eclipses (Google Maps web 3D view renders these, crazily enough, if you set your system clock to the appropriate time), more terrain and high res imagery, multispectral imagery/rendering, relativistic effects, realistic close-up rendering of planetary rings, solar flares and fancier star rendering, binary stars orbiting each other, procedural generation of plausible stars and solar systems with exoplanets in other galaxies or unobserved parts of our own galaxy. Really depends on where you want to take it!
Once a user travels to an object, would be cool to let the camera auto revolve the object slowly (in plane). Especially for kids that could be a cool feature especially you are chrome casting it your largest tv at home. So can leave it on for a while as screensaver
Super cool project! These kinds of viewers seem to pop up every few days, but this one is the best one so far. For feedback, I found it a bit odd that when selecting Sombrero Galaxy for example it zooms to the black hole M104 at the center of it, and actually viewing the entire galaxy then requires several mouse wheel spins :) Otherwise, great stuff.
Amazing work! I've been actually working on a solar system / gravity sim for my son who has been getting a lot of enjoyment out of the PhET gravity/orbit sims, that has some overlap with your project. It's up at https://newtonsorchard.app
I haven't put nearly as much time into my project as you've put into yours - Galaxium is really polished and impressive. Well done!
I had to login just to upvote
I thought it was limited to the solar system until I accidentally kept zooming out, and got my mind blown a couple of times. And again when I saw the black hole.
This is ridiculously well made
9.336 WGPU Error: Not enough memory left.
This is on a 4GB 1650 Super, latest Firefox, Win10. It's an old card, sure, but it can still play most commercial games; I'm not sure why this thing is so hungry. Lots of big volumetric textures, maybe?
This is a lovely way to explore the sights!
My feedback:
1. I wish the time scaling was persistent; I wanted to jump between solar system objects while keeping the accelerated time. A way to persist the scale would be lovely (maybe a slider in the header).
2. Pinning the object selector would be nice, too. It took me a minute to realize I could focus the text input to show the object selector again.
Hi, This is awesome to show to kids too as well. I was showing this to my 5 year old that this is earth, sun and moon this is where we are now.
The earth rotation is probably not correct, I am in UK and sun has not set yet, but in Galaxium it is showing night in UK.
Very awesome. FYI Voyager(1,2) should be oriented with the big antenna dish pointed towards Earth.
It's cool! Recently I built a space explorer-like WebGPU project inspired by Space Engine the game, and your implementation runs smooth with rich visuals, that's far superior to mine.
I do find it sometimes hard to navigate and has some visual glitches, but man it is good. I hope one day it becomes my go-to for space exploring, since Space Engine is Windows only and it does not run on my Mac. And building the space must be a huge amount of work, there's so much that has to go into it.
Galaxium can't run in this browser Galaxium uses WebGPU, a recent browser technology that isn't available or enabled here. It works in up-to-date versions of Chrome, Edge, Safari (macOS 26+) and Firefox, on a computer with hardware graphics.
In the meantime, you can explore the night sky at stellarium-web.org — it runs in any browser.
You borked it.
I think your comment could be more helpful--"You borked it" doesn't describe the problem or what you're expecting to be different.
Why do you block mobile devices? When I selected "desktop site" to bypass that it works fine, although the UI is a bit small.
Yes for now I thought it would be better to not show anything than a poor UI, and also the performance is not great on mobile right now. This is something I would like to improve for sure. Maybe a simplified version with limited UI?
I'd say just show it. Maybe with a dismissable notice saying it's not optimized for mobile. I'd saw I was getting 15-20fps, a bit janky but usable.
Very impressive. Love the motion blur on stars as you move around and fascinating to toggle on asteroids to see how busy our solar system really is.
Gee... That's fucking insane! I like it!
Btw, how many hours do you have in a day to build a non-commercial beta like this in just a year?! :D
I found several issues: 1. Selecting Voyagers and swam back in time: • The Sun was leaving a strange trace of light while moving backward through space; • When voyagers reached the Earth in 1977, they ricocheted from it and flew back into space; • When I changed the selected target during the time simulation, it stopped and lost its simulation speed 2. I can't move my cursor with arrows or Cmd | Option + <> combinations in the "Ask AI" input field
And a few thoughts from me: • You missed the favicon =) • Behavior, when you first should click on the object and then click "center" to fly to it, is a bit counterintuitive and confusing. I personally expected scroll target changes automatically when I clicked to a different object • What do you think about adding the same scale across the whole Universe (esp. in the local stars group) that the Local Group has with vertical lines from the plane of the ecliptic? • Should you add a few more DSO objects like TON 618 in the "Featured" catalog?
It’d be interesting to hear how you see this evolving and what the original idea was. Are you trying to compete with other universe exploration apps, or build it more like a browser-based atlas of the Universe?
Thanks a lot for the feedbacks! I spent quite a lot of time on this yes, though I was already quite familiar with 3d rendering and astronomical computation so it wasn't that hard. In fact the most difficult part was probably to learn WebGPU that I never used before.
For the issues:
1. Yes there are some bugs currently with the temporal anti aliasing. I was a bit aggressive on the effect because without it the Milky Way doesn't look good. I'll try to fix that (ideally it should adjust to the the velocity field).
2. All the time controls is still pretty much untested, I'll see if I can fix that.
3. I'd like to add more scale hints, but it's hard without cluttering the view. I'll see what I can do.
4. Yes at the moment there is only one black hole (sgr A*), I'll add more as soon as I can.
As for how this will evolve, I am not sure yet. I have a basic mobile version prototype working on iOS, so I thought this could turn into a mobile app at some point. No plan for an actual heavy PC app at the moment.
This looks great, amazing job! Love the motion blur effect.
Galaxium can't run in this browser
This is very cool! Is this tracking real time locations?
How much data is loaded here?
is it based on WASM？
Wow! I'm utterly speechless.
I love space "browsers" - I lose myself in them, just clicking through all the entities.
Also TIL that there are satellite galaxies, and I've never noticed those on other toys/tools like this. I always though Andromeda was the closest galaxy, but it is FAR away compared to `Sgr dSph` which is within 50kly from the center of the Milky Way.
Same here! I can't believe I never knew of the existence of satellite galaxies until now.
Amaze! Amaze! Amaze!
So cool and impressive. Very well made.
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Fuck your stupid project.