Stargazer is a Lockheed L-1011 TriStar built in 1974, that was modified in 1994 for use by Orbital Sciences (now part of Northrop Grumman) as a mother ship for the Pegasus, a small-lift launch vehicle. As of October 2022, 45 rockets (containing nearly 100 satellites) have been launched from Stargazer. Stargazer is the only L-1011 airframe still airworthy.
I was happy to discover the stargazers' forum. I definitely can't claim to be an astronomer of any description. I'm in the physics fan club, more than any kind of actual physicist.