The Aschen are a highly advanced race from P4C-970. Their technology includes medical advances that extend the lifespan and eliminate disease, transporter beams, floating harvesters, the ability to create a secondary star by igniting a gas giant, and bio-weapons designed to destroy only the specific DNA of the enemy. Although capable of space travel, they have not mastered stargate technology. They willingly offered to share their technology and protection from the Goa'uld in exchange for stargate coordinates, and Earth joined the Aschen Confederation despite O'Neill's concern that "These folks sound too good to be true."
Ten years later, SG-1 discovered that the Aschen anti-aging vaccine caused sterility in humans and the worldwide birth rate had dropped 91% in two years, leaving humanity on the brink of extinction. SG-1 devised a plan to travel back in time to change their fate, and died sending a message to the SGC ten years in the past. The note said, "Under no circumstances go to P4C-970. (signed) Colonel Jack O'Neill."
P4C-970 was locked out of the dialing computer, however SG-1 later encountered the Aschen on a mission to P3A-194 in the Volian system. Unaware of the threat the Aschen presented, SG-1 and Ambassador Joseph Faxon negotiated with Mollem and his colleague Borren for trade agreements and membership in the Aschen Confederation. Evidence of a buried city and newspaper archive on the Volian world, however, revealed the Aschen deception. A very patient people, they seek new planets to colonize, and share their technology while offering a life-extending drug that causes sterility in humans. Within a few generations the population is wiped out and the world falls under Aschen control. When SG-1 discovered the truth and broke off negotiations, the Aschen attempted to send a bio-weapon through the stargate to Earth, however it struck the iris harmlessly. Among the coordinates shared with the Aschen during the negotiations was the address to P3W-451, the planet being torn apart by a black hole. The fate of the Aschen is unknown.