Аннотация:Metal ions of refractory elements like Fe, Si, etc. at large heliocentric distances, as in comet Halley 1986 III at 0.8-0.9 AU detected with Vega-2 and Giotto in-situ measurements in March 1986, may be produced by d(IPD)- d(CometComa) high-velocity, 70-80 km/s, collisions.