The evidence that astronomers use to prove jets travel in opposite direction is Spectral lines from a very fast moving ionized gases.
<h3>Who are the astronomers?</h3>
Astronomer is a person who study astronomy which is a scientific study that has to do with space, space bodies, comets, planets, stars and so on.
Therefore, The evidence that astronomers use to prove jets travel in opposite direction is Spectral lines from a very fast moving ionized gases.
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