Unknown (Possibly Ra or himself)
|Relationship with SG-1||
"Fallout" (Mentioned only)
Thanos was a Goa'uld who occupied Langara 3,000 years ago and performed tests on naquadria. One of those tests went wrong and resulted in an explosion, which catalyzed two veins of naquadah into naquadria and killed him. (SG1: "Fallout")
The name appears to link to the Ancient Greek "Thanatos", "Death".