Gaseous anomaly
A gaseous anomaly was a type of interstellar phenomenon.

In 2290, the  began a three year mission to catalog gaseous anomalies in the Beta Quadrant. The  had been equipped with technology to do the same by 2293. ()

In 2370, Romulan Commander Sirol claimed the Terix was conducting a survey on gaseous anomalies in the Devolin system, although they were actually searching for the . ()

In 2373, the  encountered a gaseous anomaly, a class 17 nebula, containing sirillium, a highly versatile energy source that the ship's crew was eager to acquire. Upon seeing the anomaly, Lieutenant Tuvok experienced a medical episode, followed by a flashback to the time when he served aboard the USS Excelsior in 2293. In the flashback, Commander Janice Rand commented that the vessel's crew was protecting the Federation from gaseous anomalies, a sarcastic reference to them have being tasked with this tedious work. ()

nl:Gasachtige anomalie
Celestial objects