TEST

On clear or partly sunny days, people might look up at the sky and see straight lines of what appear to be clouds or white smoke. These lines are not smoke or natural clouds; they are contrails produced by aircraft. Contrails form because water vapor from jet engine exhaust passes through a cold and humid part of the air at high altitudes. Sometimes the jet that created the contrails is not visible overhead because winds aloft have blown the vapor trail into the observed area after the jet has passed. Naturally occurring high thin cirrus clouds do not form straight lines, they are more diffuse and irregular in shape than a contrail. Can an app be developed to help a ground observer determine the probability that an aircraft made the thin lines of white 'clouds' overhead?

TEST. 1

TES