Lunar and Planetary Science XXXII (2001) 1510.pdf CRATER CHAINS ON MERCURY. V. V. Shevchenko and T. P. Skobeleva, Sternberg State Astronomical In- stitute, Moscow University, Universitetsky 13, Moscow 119899, Russia,
[email protected] Introduction: After discovery of disruption comet It was examined many images from the Mariner 10 Shoemaker-Levy 9 into fragment train before it’s colli- set and there were identified a total 15 crater chains sion with Jupiter there was proposed that linear crater and were unable to link any of these directly chains on the large satellites of Jupiter and on the to any specific large crater associated with ejecta de- Moon are impact scars of past tidally disrupted comets posits. Chain craters are remarkably aligned. All dis- [1 - 4]. tinguished crater chains are superposed on preexisting It’s known that radar images have revealed the pos- formations. sible presence of water ice deposits in polar regions of Chain Morphology: A total 127 craters were Mercury. Impacts by a few large comets seem to pro- identified in the 15 recognized crater chains. The vide the best explanation for both the amount and number of craters per chain ranges from 4 to 11. cleanliness of the ice deposits on Mercury because they Fig. 2 shows that crater diameters range from 3 to have a larger volatile content that others external 13 km, with an average of 7 km. Crater statistics dem- sources, for example, asteroid [5]. onstrates remarkable uniformity of the crater popula- A number of crater chains on the surface of Mer- tion of the chains.