Goa'uld spy satellite
From The Stargate Omnipedia
Satellite of Goa'uld design, capable of transmitting sensitive telemetry across many light years to the proper receiving equipment, such as a database with a Goa'uld holographic projector.
KEY EPISODE
Beachhead - Nerus uses his spy satellite near Kallana to update General Landry and SG-1 on the status of an Ori force field as it gradually encompasses the planet.