Talk:Long Endurance Rovers

I don't have time to edit this page right now, so I'm going to summarize what I see as some of the problems.

Organization

The various sub-topics seem to be spread around at random

Content

No mention is made of the Russian "Lunokhods" (generally considered teleoperated rovers, although they were provided with manual controls). Lunokhod 1 operated for almost a year, & Lunokhod 2 for about 6 months. Their landing sites were in relatively high latitudes, where the daytime temperature peaks are lower, & they hibernated during the night with a very clever mechanism (heat radiators were located under a "lid" which was opened when the interior got warm & shut when it got cold).

The cooling mechanism described for APOLLO is wrong. There was an "oxygen purge system" in the PLSS (backpack), but it was purely a backup in case of a failure of the primary system, which didn't actually happen. Suit cooling was provided by a flash-evaporator using water. The LEM was cooled primarily by radiation, with an evaporator for use under higher heat loads. (As a side comment, if we are going to waste anything, oxygen is not a bad choice, being the most abundant single element in Luna & one of the easiest to produce.)

Some of the items just don't belong in this article, e.g. the description of sun-shield berms (which work better in middle and high latitudes anyway).

The description of the "parabolic reflectors" is much too specific in terms of defining the shape, & in any case a diagram or sketch would be preferable. Excessive specificity strikes again elsewhere in the description -- it's not clear why the heat-circulating fluid should be "a mixture of water and ethylene glycol" rather than, say, alcohol, sodium-potassium alloy, or any of a number of other suitable liquids, or why it should be a liquid rather than a gas (e.g. helium), or a a phase-change fluid ("heat-pipe" radiators have proven very effective). "Sintered brick shelters" & "pumped storage of high-pressure oxygen", although possible approaches for night shelter & power storage respectively, are certainly not the only possible ones, & need evaluation.

-- publius 04:07, 9 November 2008 (UTC)