Many comets have two tails, a gas tail(also call ionic tail or plasma tail) composed by ions by the shock of the solar wind with the comet, and the dust tail, composed by released particles of the nucleus when vaporizing itself the ice. The dust particles are had following the orbit the comet and they move slightly by the pressure of the solar radiation, reason why they tend to curve itself with respect to the ion tail. The plasma tail frequently shows structures associated with variations of the ejection rate of the nucleus in the time. The ionic tail normally is blue, narrows and straight line, whereas the dust tail is more diffuse, wide, often curved and of whiter color. These differences of aspect directly are correlated with the different origins and compositions from both tails.