We don't have synonyms for blue jet yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are blue jay, blue tit and blue jean.
(n) :
(astronomy, meteorology) An upper atmospheric optical phenomenon associated with thunderstorms, a rapidly expanding disk-shaped region of luminosity, lasting less than a thousandth of a second, which occurs high above energetic cloud-to-ground lightning of positive or negative polarity.
(n) :
(astronomy, meteorology) An upper atmospheric optical phenomenon associated with thunderstorms, a rapidly expanding disk-shaped region of luminosity, lasting less than a thousandth of a second, which occurs high above energetic cloud-to-ground lightning of positive or negative polarity.