Word: silicones
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Dates: during 1950-1959
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...satellite, a magnesium sphere with a surface of silicon monoxide to keep it at proper temperature in sun or shadow, was put into a spin of about 50 r.p.m. The spin made it act like a gyroscope, keeping its axis always pointing in the same direction in space. At its perigee, the axis is parallel to the earth's surface. But a quarter of a revolution later the axis points vertically at the earth (see diagram). At apogee, the axis is parallel again...
Vanguard I might seem too small (diameter: 6.4 in.; weight: 3.25 Ibs.) to carry much cargo, but an amazing amount of delicate apparatus was packed into it. Most novel items: its six solar batteries made of subtly treated silicon that look out through windows distributed over the sphere in such a way that at least one of them is always facing the sun. Each battery develops about 25 milliwatts of power when in sunlight, and feeds a miniature transmitter that broadcasts continuously on 108.03 megacycles. Another transmitter, powered by a mercury battery, broadcasts on 108 megacycles...
Besides being useful for tracking the tiny sphere by radio, the transmitters report the temperature inside it. The surface of the sphere is made of shiny aluminum covered with a thin coat of silicon monoxide. This material is transparent to visible light from the sun, which it permits the polished aluminum to reflect back into space. But it looks black to the long infra-red (heat) waves. Since black surfaces radiate well, it permits the satellite to get rid of its internal heat by radiation. The system seems to be working well. Both transmitters have reported that the temperature inside...
Brooks, a Gordon McKay Professor here since 1950, has done research in the cohesive energy of alkalis, metal interfaces, lattice imperfections in metals, and the theory of electrical properties of germanium and silicon...
...Freeze. The two outer layers determine the satellite's reaction to solar radiation. Silicon monoxide is transparent to visible light, so the powerful visible part of the sun's radiation penetrates to the shiny aluminum and is mostly reflected back into space. The temperature of the aluminum rises slowly, both because it is a poor absorber and because the silicon monoxide layer in contact with it is a comparatively good radiator of infra-red (heat) rays. By experimenting with different thicknesses of silicon monoxide, the Navy's scientists think they can keep the temperature of the skin...