I have the idea of a few Tenno being unable to move on when faced with the truth from recent events, banding together, lost in despair, sailing off into the unknown to become a kind of "ghost ship". The captain would sing each verse, with the rest of the crew replying with the chorus, in time to the words in bold, in a kind of dirge. Perhaps someone finds this scratched into a wall, with a group of inert warframes scattered throughout the ship...
The Serpent with a Siren's song,
Fled to where the soulless belong.
Great deceiver, lied all along,
When faced with truth her light is gone.
"Sailing through the ether,
No safe harbour in mind.
Homeless but determined,
We'll remember what we find.
Drifting through the ether,
No happiness inside.
Hopeless and dejected,
No matter what we find.
Lost unto the ether,
No life in heart nor mind.
Nothing more to say here,
For here's the only home you'll find.