Waste-heat rejection from the satellites will also make them the brightest objects in the night sky next to the moon in the far infrared region (peak radiation ~9p) Douglas et al. estimated that the intensity of the radiation from a satellite will be about equivalent to that of the moon throughout the infrared region, but they note that the moon occupies a much larger solid angle. However, they suggest that "even many hundred satellites should not be expected to cause a detectable sky illumination at far infrared wavelengths.” This statement is based on the fact that as Douglas et al. point out, "the main component of sky radiation in this region of the spectrum is thermal emission from the lower atmosphere." The satellites, due to construction operations, weathering by cosmic and solar ray bombardment, gas leaks, etc., will serve as relatively diffuse sources of assorted gases and particulate matter as well as of larger debris. Vondrak (Refs.3.14 and 3.15) has taken a preliminary look at the potential for forming relatively long-lived clouds of gas and dust in cislunar space (between Earth and Moon). Vondrak claims that (1) the dominant loss mechanism for gas clouds, if they are indeed formed, would be interactions with the solar wind; (2) the presence of such a gas cloud would become important when its mean density is large enough to divert the solar wind flow (this would require a gas leak rate of about 600 kg/sec); (3) significant absorption of the solar ultraviolet light would occur at comparable leakage rates; (4) interactions of solar wind with clouds of gas or dust may influence the Earth’s weather and climate by altering the amount of solar radiation received by the Earth. In view of the large emission rates required to produce a significant effect, it is not at all clear whether or not the SPS will present a hazard along the lines Vondrak has suggested. Before such questions can be addressed it will be necessary to make some reasonable estimates of the strength of the source terms. If indeed clouds of gas or dust of significant mass density can form and remain in orbit for extended periods, then a possible consequence aside from the effect on the terrestrial environment may be the effects on the satellite environment that may impair its operation. Douglas et al. (Ref. 3.13) have examined the problem from this point of view. They mention four areas that they feel deserve quantitative investigation: 1. Sources, types and quantities of particulates emitted; 2. The concentrations that will build up and possible dispersal effects;
RkJQdWJsaXNoZXIy MTU5NjU0Mg==