▁that ▁so ot ▁is ▁not ▁formed ▁and ▁complete ▁comb ust ion ▁occurs . ▁Exper iments ▁by ▁NASA ▁reve al ▁that ▁diffusion ▁fl ames ▁in ▁micro ▁gravity ▁allow ▁more ▁so ot ▁to ▁be ▁completely ▁ox id ized ▁after ▁they ▁are ▁produced ▁than ▁diffusion ▁fl ames ▁on ▁Earth , ▁because ▁of ▁a ▁series ▁of ▁mechan isms ▁that ▁behave ▁differently ▁in ▁micro ▁gravity ▁when ▁compared ▁to ▁normal ▁gravity ▁conditions . ▁These ▁discover ies ▁have ▁potential ▁applications ▁in ▁applied ▁science ▁and ▁industry , ▁especially ▁concerning ▁fuel ▁efficiency . ▁ ▁In ▁comb ust ion ▁engines , ▁various ▁steps ▁are ▁taken ▁to ▁eliminate ▁a ▁fl ame . ▁The ▁method ▁depends ▁mainly ▁on ▁whether ▁the ▁fuel ▁is ▁oil , ▁wood , ▁or ▁a ▁high - energy ▁fuel ▁such ▁as ▁jet ▁fuel . ▁ ▁Fl ame ▁temper atures ▁ ▁Tem per atures ▁of ▁fl ames ▁by ▁appearance ▁It ▁is ▁true ▁that ▁objects ▁at ▁specific ▁temper atures ▁do ▁radi ate ▁visible ▁light . ▁Object s ▁whose ▁surface ▁is ▁at ▁a ▁temperature ▁above ▁approximately ▁ ▁will ▁g low , ▁em itting ▁light ▁at ▁a ▁color ▁that ▁indicates ▁the ▁temperature ▁of ▁that ▁surface . ▁See ▁the ▁section ▁on ▁red ▁heat ▁for ▁more ▁about ▁this ▁effect . ▁It ▁is ▁a ▁mis con ception ▁that ▁one ▁can ▁judge ▁the ▁temperature ▁of ▁a ▁fire ▁by ▁the ▁color ▁of ▁its ▁fl ames ▁or ▁the ▁spark s ▁in ▁the ▁fl ames . ▁For ▁many ▁reasons , ▁chem ically ▁and ▁opt ically , ▁these ▁colors ▁may ▁not ▁match ▁the ▁red / or ange / yellow / white ▁heat ▁temper atures