re command loss timer re galileo update prb access digex com pat writes galileo s hga is stuck the hga was left closed because galileo had a venus flyby if the hga were pointed att he sun near venus it would cook the foci elements question why couldn t galileo s course manuevers have been designed such that the hga did not ever do a sun point the hga isn t all that reflective in the wavelengths that might cook the focal elements nor is its figure good on those scales the problem is that the antenna itself could not be exposed to venus level sunlight lest like icarus wings it melt i think it was glues and such as well as electronics that they were worried about thus it had to remain furled and the axis always pointed near the sun so that the small sunshade at the tip of the antenna mast would shadow the folded hga a larger sunshade beneath the antenna shielded the spacecraft bus mark looper hot rodders america s first recyclers
