Analysis of spikes in occultation curves: A critique of Brinkmann's method

Brinkmann's method of deriving the composition of a planetary atmosphere from the timing of occultation curve spikes is discussed in detail. Contrary to the statement made in Brinkmann's paper, it is shown that not only must the spikes be timed, but the intensity of the background occultation curve must be determined at the points at which the spikes occur. The fact that the method does depend on intensity measurements introduces significant uncertainties in practice, so that the method is not as powerful as previously supposed.