A couple of points not mentioned:
The Moon did have an atmosphere back when it had a lava ocean. It lasted probably 70 million years or so, and I believe was about 100-1000 Pascals, or slightly less than to slightly more than the atmospheric pressure on Mars. There are a number of different estimates for the density and age of the lunar atmosphere.
I think this is a contrail effect just like those caused by aircrafts.
Both aircraft jet fuel and rocket fuels like RP-1 and liquid hydrogen produce a lot of water vapor when burned within the respective engine.
Depending on the temperature and humidity at the altitude the
contrails form, they may be visible for only a few seconds or minutes,
or may ...