New Celestia Star Textures

[MrSpace43]

So a few days ago, I started work on new 8k star textures to use for Celestia. So far I have completed 4 star types (one of which is that Sun texture I posted a while ago), and I plan to make more of these textures, and to release them.

These are the textures for the star types I have completed (F-type, G-type, K-type, and D-type)

Added after 44 minutes 40 seconds:
New textures for O-type, B-type, and A-type stars.

[MrSpace43]

After finding some more pics of the sun with large sunspots, I updated my K-type star texture to incorporate them.

[MrSpace43]

New G-type star texture with more starspots.

Comparison between Alpha Centauri A (right) and our Sun (left) using my 8k SDO April 2014 texture:

I think I might update my K-type & F-type textures to have more starspots too (albeit the latter will have less than the G-type).

Added after 4 hours 57 minutes:
The K-type star texture has been updated again, and is now packed to the brim with starspots.

[MrSpace43]

O-type, B-type, and A-type textures have been updated. They now use low wavelength UV data (~304 angstroms):

[MrSpace43]

New Wolf Rayet star texture made using extreme UV data (~193 angstroms):

[bh]

Okay... how are these installed?

[MrSpace43]

If you mean how they are installed to Celestia, you just move them to the "textures" folder (not the "extras" folder). Then you delete the old star textures that you had previously, and then edit the celestia.cfg file to add the new star textures.

I haven't finished making all the textures needed though, so because of that, they are not available to download for now.

[MrSpace43]

New texture for Y-type brown dwarfs (only works in 1.6.2 onwards) using acrylic pour:

This is easily one of the darkest textures I have ever made.

[The Minmus Derp]

These look amazing! I can't wait to use them in my install

[MrSpace43]

New texture for T-type brown dwarfs, again using acrylic pour:

[MrSpace43]

Been a while since I touched this topic due to other hobbies and stuff, but after I had a look at this paper, I have updated my white dwarf texture so that it now has surface granules. I decided to keep some details from my old texture that used UV data, so I used it for some bright spots and a few subtle dark patches, just so that it doesn't look dull and featureless when viewed from a distance.

[MrSpace43]

It's been some time since I've done anything with these textures, but now that enough time has passed, I think there are some textures which I think are in need of being revamped.

Finished:
O, B, A, F, G, K, D

In need of a revamp:
T, Y, WR

Not yet made:
M, C, L, Pulsar


T-type:
I'm thinking of making a new texture based off simulations of brown dwarf atmospheres (though I have absolutely no idea as to how I'd tackle making such a texture that resembles these simulations), and I'd also like to see if I can incorporate some bits of magenta into the texture.

Concept texture made using a still from Fig. 27c:

Y-type:
I just imagine it could be made from various bits of Jupiter and Saturn maps.

WR-types:
I'm gonna stick to using ~193 angstrom data, though I'm going to use different Sun images from SDO with more solar activity.

M-type:
Due to a lack of high resolution images of the sun's surface that have licenses which permit commercial usage, I'm stumped with what data I can use for M-type main sequence stars. And before anyone asks, I can't use SDO data because the resolution isn't good enough for large starspots, so the best resolution I can do for an M-type texture with SDO data, is only 2K instead of 8K.

As for L-type, C-type, and pulsars, I have absolutely no idea how I should tackle the textures for these classes.

[MrSpace43]

So after a bit of discussion on the Celestia Discord server about the appearance of L-type brown dwarfs, I came up with this draft texture that I made using bits from Hubble Jupiter maps, along with the poles from Björn's Cassini Jupiter map:

This texture isn't final, and will be subject to change as we continue to discuss what L-type brown dwarfs would look like, and how that could be applied when making a new L-type texture for Celestia.

[MrSpace43]

So recently me, Chara, cubic, and pedroJ have been discussing in the Discord server about the new star textures, and how we're going to be making them the vanilla textures for 1.7.0 with new colors from Askaniy's True-Color Tools. With this discussion on how certain stars would look like, I have made some changes to the textures that I've already made, and they are as follows:

O-type and B-type:
These textures have been completely redone, now using SDO data with wavelengths of ~1600 angstroms, to simulate the lack of any surface granules.

A-type:
As it turns out, the transition from a granulated surface to a radiative surface, is at around ~9000-10000 K, which overlaps the temperature range of A-type stars (~7300-10000 K). As a result, we ultimately decided to give the A-type star a granulated surface to simulate an A-type with a cooler temperature. It's also mentioned in some papers about A-types with bright spots, so we've also mixed in some ~304 angstrom data to add brightness variations.

F-type, G-type, K-type, and D-type:
Nothing's changed for these, aside from the colors, and that D-type has lost the brightness variations.

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The quest isn't over yet, as we're still having discussions on what to do for the other spectral types that don't have new textures yet.

M-type:
Hopefully we're looking to see if we could go for something that's more-or-less akin to the simulations (shown below) of what red dwarfs might look like. It hasn't been fully settled, but perhaps we could see about using close-up photographs of the sun's granulated surface.

L-type and T-type:
We're hoping to see if we can try to replicate these simulated maps from this paper (and shown below), and while it hasn't been settled yet, perhaps we could see about utilizing photos of Earth's clouds, and maybe even bits from maps of Jupiter and Saturn, to make textures for both L-type and T-type brown dwarfs.

Y-type:
Honestly the texture should just resemble a typical gas giant, akin to Jupiter or Saturn (maybe a mix of the two).

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We have also had some discussions for the other remaining star types, although there hasn't been as much discussion with them as for the other star textures above, but here's some ideas for how to tackle them:

WR-types:
There's been no discussion on these, although I reckon they could just re-use the textures for O-type or B-type.

Red Giants/C-types:
Chara mentioned this while I was making concept textures for main-sequence M-type, when they mentioned that we could just use close-up pics of solar granules, as red giants (as well as red supergiants) are believed to have large convection cells, as demonstrated by the simulation below:

Pulsars:
Not much discussion on this one either, but cubic did mention that perhaps we could make something using photos of rheoscopic fluids.

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I'll update this list whenever we've finalized the designs of textures, or if we decide to take a different approach for others. This is the just where we're at for the moment, and there's bound to be some change of plans on how we're going to make these textures.