I was reading the wiki entry for sentients and the notes mentioned tau possibly being the tau ceti system, with the ceti lascetera's name being the only backup. Tau cant be the Ceti system because its only got one star, so that got me thinking.
TL;DR: Its the Tau Boötis system, fight me about it. Expanded reasoning below, its very long.
My Theory is that the Tau we went to it Tau Boötis (which i will be typing as bootis for the remainder of this post because i cant type the ö).
Tau bootis is a binary star system 51 light years from earth that has a red dwarf and a F-type main-sequence star orbiting each other, and at least one planet.
Planet first. We dont know very much about the planet orbiting the binary stars. Its called Tau bootis B, i'll just type is as B because im lazy. B is a gas giant. I dont really know this for a fact, but i believe its an actual thing that Gas giants tend to have moons for several reasons. Our entire time on tau is spent on a moon (perita) so its completely possible that we are on a moon orbiting the IRl exoplanet B.
Picture of the in game skybox from the Trauma manifestation scene. its not super clear due to the shadow and filter over the entirety of tau, but this planet appears to have a gas covered surface. The smaller planet in front is just a scaled down version, but that was likely a time saving measure.
Now for the stars, which are my main point.
The Stars of Tau bootis are, as mentioned, a F-type main sequence star and a red dwarf. The larger star is about 42% larger than our sun, and the red dwarf is about half the size of the sun, and quite dim in accordance with most dwarves.
I didnt see what colour the large star in the Tau bootis system is, but this photo of it is pretty distinctly blueish. A picture isnt concrete proof of a star's colour, so I looked up a Conventional colour classification chart as well, and it looks like the large star of the tau bootis system would be a blueish hue. F type stars tend to appear whiter in space due to their temperature, but i think a combonation of tau's blueish filter and the fact that this is a videogame means that eyeballing colours isnt completely reliable all the time.
Im having a hard time finding the name of the red dwarf in the Tau bootis system which is making it difficult to search up info about it. It will probably strike you immediately that the star we see on tau in game isnt very red, but it seems like red dwarves are actually a yellowish orange hue irl, and combining that with the filter mentioned above means that once again, you cant just eyeball the colours beyond an estimate.
This screenshot was taken with bloom turned off so you can more clearly see the stars, which seemed to take away that reddish hue that was there earlier. I dont think the reddish colour of the bloom should be discounted, but i thought i should note that down
The sizes of the stars are also notable. Since the sizes of the two stars IRL are known, i compared the sizes of the in game stars. Luckily, the skybox in most of the Perita scenes doesnt have a boat load of VFX obscuring it, so i got this
I then brought it into my art program and did some basic stuff. I apologize for the thin lines, i wanted to be precise.
My measurements of the stars in game definitely arent exact, and theres no way in hell that DE precisely measured the stars in the skybox to be real world accurate. The fact that the stars might not be the same distance from Perita would also effect the visual size. The stars have a very weird orbit IRL and get as close as 28 AU apart, so theyre probably very close here. the orbit takes about 2400 years to complete. given all that, i would say the sizes of the in game stars are comparably close to the sizes of the IRL stars.
Its past midnight and ive been yammering about this theory in the warframe discord for a while, so im cutting myself off here. i dont know why you would read all this, but i hope someone does. Im very open to suggestions and additions to this theory so please add to it. If any astronomers read this i am deeply sorry.
I spent way too much time on this piece lol but I wanted all of the Sentient stuff I had in one shot haha. I wish I had shot them all on a green screen but nooo I had to shoot them all in the scene. Anyway, below is my first attempt.
I think I'm going to try more of these with different faction skins and themed Warframes. Should make for fun compositions.