Post by PhantomWolf on Dec 11, 2006 20:42:45 GMT -4
Interesting little story I just stumbled across.
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John Saxon, who served as Operations Supervisor at NASA Honeysuckle Creek Tracking Station, Australia, during Apollo writes, "I should share one of my best ALSEP tracking stories. One of the nice things about the Manned Spaceflight Network ground equipment was that we could decommutate the Telemetry, and display spacecraft - and astronaut - parameters on strip chart recorders and other devices. After the excitement of the manned sections of the Apollo missions, supporting the ALSEP packages could seem rather routine - so we often checked temperatures, seismic activity, etc. One quiet evening we noticed that one of the usually fairly dull seismometers was outputting apparently random, short, sine-wave activity superimposed on the background activity. These were obviously artificial artifacts, but no one on site could work out what might be causing them. So I checked with the on-duty ALSEP controller at Houston, who came up with the answer immediately. 'Oh - what you are seeing is the Mylar heat insulation which is spread around the seismometer. The sun is just rising in the lunar dawn at the site and the insulation is warming up and pinging as it changes shape'. A bit like a biscuit tin lid when you flex it. So that was an unintended temperature change sensor."
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John Saxon, who served as Operations Supervisor at NASA Honeysuckle Creek Tracking Station, Australia, during Apollo writes, "I should share one of my best ALSEP tracking stories. One of the nice things about the Manned Spaceflight Network ground equipment was that we could decommutate the Telemetry, and display spacecraft - and astronaut - parameters on strip chart recorders and other devices. After the excitement of the manned sections of the Apollo missions, supporting the ALSEP packages could seem rather routine - so we often checked temperatures, seismic activity, etc. One quiet evening we noticed that one of the usually fairly dull seismometers was outputting apparently random, short, sine-wave activity superimposed on the background activity. These were obviously artificial artifacts, but no one on site could work out what might be causing them. So I checked with the on-duty ALSEP controller at Houston, who came up with the answer immediately. 'Oh - what you are seeing is the Mylar heat insulation which is spread around the seismometer. The sun is just rising in the lunar dawn at the site and the insulation is warming up and pinging as it changes shape'. A bit like a biscuit tin lid when you flex it. So that was an unintended temperature change sensor."