Mostly in Star Trek, but in other Hollywood-style sci-fi as well, there is a very common, very persistent, extremely ignorant error that crops up.
Out in deep space, away from any star, our intrepid heroes encounter a “rogue comet” and that comet, out in deep space away from any star, has a tail on it. A comet’s tail.
A comet’s tail is formed when it gets close enough to a star for the volatiles (frozen oxygen, water, co2, etc) heat up enough to “melt” (200 below zero Fahrenheit is enough for some of it) and solar wind pressure (again, from the star) causes these now-vapors to stream behind the comet, because the comet is hurling toward that same star, either locked in to a long-period recurring orbit or a one-time intruder into that solar system just saying “hi” for a moment, and depositing some of it’s material into that solar system in the process (which is one way particles move around in the galaxy.
In deep space — away from a star — there can be no comet tail. No vapor cloud (unless it’s large enough to classify as a planet or planetoid rather than a “comet” — in which case the vapors would be an atmosphere… or not. Out in deep space, away from any star and a star’s warmth, that “atmosphere” will more likely lie frozen all over that object’s surface, if it’s that large).
Though you maybe could have life forms there… very slow, perhaps anaerobic (happy without oxygen, that is), perhaps not. Main stream science — including NASA — has very little imagination when it comes to other forms of life.
Short version: Hollywood: Cut it out!!!!
(Suggestion: You could hire an 8th grader to correct some of these science errors you persistently do. JJ Abrams’ sci-fi and such works from other director / producers could all benefit from such science advisors. Can’t even begin to imagine what would happen if y’all hired real scientists for advisors and then actually listened to them… wow)
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