For discussion of everything rum and uncanny, from cryptozoology (mysterious or out-of-place animals), UFOs, high strangeness, etc. Following in the footsteps of Charles Fort and all those inspired by him, like the field of anomalistics.
As this community is on Feddit.uk it takes a British approach to things but it needn't be restricted to the UK - if it's weird and unusual it probably has a home here.
Elsewhere in the Fediverse:
Exobiology is always tricky as we are relying on extrapolating from terrestrial chemical processes and things could get weird out there. Or they could be very familiar.
That said, the sulphide is a promising sign.
Not really forteana, but forteana adjacent.
My rule-of-thumb is "would it fit in the Fortean Times and adjacent publications?" and I am pretty sure this would.