Harlan is the last survivor of the planet Altair, a jovial soul in a synthetic body many thousands of years old. He had lived alone on Altair for more than 11,000 years, and he created synthetic versions of SG-1 as companions to help him maintain the aging underground power facility that was his home. When the synthetic duplicates continued to go on missions, and were in jeopardy on Juna, Harlan came to the SGC pleading for help to rescue them. He did not participate in the rescue mission, and presumably returned to Altair alone when the duplicates were destroyed in the battle for Juna.
Portrayed by: Jay Brazeau