Comets

There is another possibility that remains unexamined. It takes account of the obvious electrical nature of comets, which is the only model to successfully predict what would be found by the Deep Impact experiment.

The flaw in the conventional approach is that only gas-phase chemical reactions and reactions induced by solar radiation (photolysis) are considered. The far more energetic molecular and atomic reactions due to plasma discharge sputtering of an electrically charged comet nucleus are not even contemplated [see below]. Yet this model solves many comet mysteries that are seldom mentioned.

The hydroxyl radical, OH, is the most abundant cometary radical. It is detected in the coma at some distance from the comet nucleus, where it is assumed that water (H₂O) is broken down by solar UV radiation to form OH, H and O. It is chiefly the presence of this radical that leads to estimates of the amount of water ice sublimating from the comet nucleus. The comas of O and OH are far less extensive than the H coma but have comparable density.

The negatively charged oxygen atom, or negative oxygen ion, has been detected close to cometary nuclei. And the spectrum of neutral oxygen (O) shows a "forbidden line" indicative of the presence of an "intense" electric field. The discovery at comet Halley of negative ions puzzled investigators because they are easily destroyed by solar radiation. They wrote, "an efficient production mechanism, so far unidentified, is required to account for the observed densities." And the intense electric field near the comet nucleus is inexplicable if it is merely an inert body ploughing through the solar wind.

Let's see how the electrical model of comets explains these mysteries. The electric field near the comet nucleus is expected if a comet is a highly negatively charged body, relative to the solar wind. Cathode sputtering of the comet nucleus will strip atoms and molecules directly from solid rock and charge them negatively. So the presence of negative oxygen and other ions close to the comet nucleus is to be expected. Negative oxygen ions will be accelerated away from the comet in the cathode jets and combine with protons from the solar wind to form the observed OH radical at some distance from the nucleus.

The important point is that the OH does not need to come from water ice on, or in, the comet. Of course, some water is likely to be present on a comet or asteroid. It depends upon their parent body. And since there are many moons in the outer solar system and the rings of Saturn with copious water ice, we may expect some smaller bodies like comets and asteroids to have some too. But what is obvious from the closeup images of comet nuclei is that they look like dark, burnt rocks. They do not look icy. Their appearance fits the electrical model and not the poorly consolidated dirty ice model.