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The ratio of CH4/CO in comets is an important indicator of the region of their formation. However, it is difficult to measure the quantity of CH4. The Giotto Ion Mass Spectrometer experiment observed a quantity of CH+which seemed inconsistent with the amount of CH4observed. Thus, it was proposed that a source of the CH+was a distributed source in the dust. We tested this hypothesis by observing the CH emission strength in comet Hale–Bopp as a function of dustiness. We see no strong correlation between the dust and the gas. Thus, for Hale–Bopp, dust is unlikely to be a dominant source of CH.