Atmosphere test capsule
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The atmosphere test capsule is a tubular device used to rapidly determine the viability of a planetoid's atmosphere. Depending on the chemical reaction after exposure, a visibly colored strip within the tube will either indicate green for viable or red for the opposite.
In one such instance, upon parachuting upon a red moon following a skirmish, Kara "Starbuck" Thrace breaks the seal of a test capsule to find that the moon did not have a suitable atmosphere (TRS: "You Can't Go Home Again").