ntrs.nasa.gov: I. Effects of Dust on Surface Operations From experience on Earth it might appear that dust on a planetary surface, be it the Moon, Mars, or any of various asteroids, would be a nuisance but not a serious problem. During the NASA campaign of the 1960’s the principal dust concern was that spacecraft might sink into fine particles on the surface, and perhaps even be lost. But Ranger 7 photographs in 1964 showed “a big rock sitting calmly on the surface and not sinking out of sight. So thus anybody in his right mind would conclude that the bearing strength of the lunar surface was not an issue.” 1 When the major fear was shown to not be an issue, attention turned to other challenges of landing and working on the lunar surface. The dust mitigation equipment carried to the Moon by the first Apollo astronauts consisted of a 4” brush for dusting off equipment and spacesuits, and a finer brush for the camera lenses. But lunar dust was found to cause both more problems and more severe problems for the Apollo astronauts then anyone anticipated. 2 The first dust-related problems experienced by the Apollo astronauts occurred when they landed the Lunar Module (LM). The Apollo 11 crew reported that “Surface obscuration caused by blowing dust was apparent at 100 feet and became increasingly severe as the altitude decreased.” This was even more of a problem for Apollo 12 where there was total obscuration in the last seconds before touchdown to the extent that there was concern that one of the landing feet could have landed on a boulder or in a small crater. In addition during the Apollo 12 landing the velocity trackers gave false readings when they locked onto moving dust and debris during descent. Dust set into motion by the landing rockets continued to a greater or lesser extent for all of the Apollo landings. But even more severe issues faced the astronauts once they left the LM and started to move about the surface. Dust was found to quickly and effectively coat all surfaces it contacted, including boots, gloves, suit legs, and hand tools. Consequences included the Apollo 11 astronauts repeatedly tripping over the dust covered TV cable, and a contrast chart on Apollo 12 becoming unusable after being dropped in the dust. This was particularly troublesome on Apollo 16 and 17 when rear fender extensions were knocked off of the Lunar Roving Vehicle (LRV) and dust “rooster tailed” and showered down on top of the astronauts. Dust coating was the precursor to other problems such as clogging of mechanisms, seal failures, abrasion, and the compromising of thermal control surfaces. In addition, valuable astronaut time was spent in ordinary housekeeping chores like brushing off and wiping down equipment – which often proved ineffective. For example, Pete Conrad noted that the suits were more worn after 8 hours of surface activity that their training suits were after 100 hours and further reported that their spacesuits were worn through the outer layer and into the Mylar multi-layer insulation above the boot. Gauge dials were so scratched up during the Apollo 16 mission as to be unreadable. And after falling onto the surface, Harrison Schmitt reported that the sun shade on his face plate was so scratched that, because of the glare, he could not see out in certain directions. Further, an insulating layer of dust on radiator surfaces could not be removed and caused serious thermal control problems. On Apollo 12, temperatures measured at five different locations

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