Yeah not in a way detectable to radio telescopes though. If an atmosphere is stoichemetrically ‘far’ from equilibrium, this implies a biogeochemcical process that is pushing it out of equilibrium.
Oxygen very quickly gets reduced out of the atmosphere. Thats the whole point of it as a bioindicator molecule. There aren’t many other species of molecule that are such a clear indicator of the presence of redox reactions. Preter oxidative respiration, If nitrogen was the electron receptor, but its species like ammonia might be visible via radio telescope. Google great oxygen holocaust. We know photosynthesis was happening before then, but oxygen wasn’t the terminal electron receptor.
Oxygen would be a smoking gun, because you don’t keep oxygen in an atmosphere if something isn’t replenishing it.
I also got about 1/2 way through typing almost the same response below about gases that naturally degrade quickly, not being able to accumulate to high enough concentrations to be detectable at these distances but @TropicalDingDing did so more eloquently than their name would indicate possible, so I’ll let you read theirs here: lemmy.world/comment/8258449
It’s a good biosignature but a real smoking gun would be if a planet has intelligent life that’s not always so intelligent. Then, we might detect chlorofluorocarbons or some other synthetic pollutant.
“Well, we detected an alien civilization but their atmosphere is in way worse shape than 1950’s London and they’re 100 light years away. I guess we’ll keep checking and see if they get their act together or not.”
The time thing is interesting, but I feel like no one talks much about the appearance of passing objects. That is, I wonder how the image of a passing celestial object might distort due to length contraction and any other effects. I’m still trying to understand that. This article seems pretty digestible, so far.
Are those… Philips screws? Looks like maybe two dots indicating JIS (shallower angle, less cam-out, and #1 cause of stripped screws on Japanese motorcycles) but I’d really like to know why a hex or torx screw wasn’t used
I was curious about that too. They look like Torq-set to me, being that the slots are offset from the center of the screw. If that’s the case they’re shouldn’t be any cam out at all.
In either case the fasteners that were stuck appear to be Hex head, and the phillips looking fasteners just held a protective cover in place (?)
I would imagine NASA would know better than to use Philips for anything lol.
By the way there is a link on the page to more images of the assembly
astronomy
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