MSL SOL 200 ANOMALY AND OTHER MSL ANOMALIES
Updated on 8/20/2015.
On September 1, 2012 I noticed that the Rover Environmental Monitoring Station (REMS) team (who worked for JPL/NASA) published a Martian surface pressure that was similar to what might be expected for Vail, Colorado (742 hPa). I immediately called Guy Webster, JPL publicity man, to advise him that if true, he needs to have President Obama make an announcement that MSL has discovered Mars has air pressure like that on Earth. Webster told me that he would pass the problem on to Ashwin Vasavada, the Project Scientist for MSL. The higher pressures continued for 5 days. On September 5, 2012 the pressure reported was 747 hPa. But the next day, September 6, 2012, the pressure reported was 747 Pa (not hPa). The new pressure was like swapping 747 dollars for 747 cents. See Figures 1 and 2. It was one hundredth of the previous day’s pressure and close to a vacuum again. By this time it was apparent that there were many serious problems with MSL and the credibility of those (in Spain) who were responsible for reporting on Martian weather. NASA was very slow to admit that it had real problems with all its weather data. But in Chapter 8 of the book Mars Up Close we are given a close up of “The Anomaly” that almost shutdown MSL on its 200th day. The computer that was supposed to turn off some of the equipment at about 2 pm local time on Mars was not doing its job.
Figure 1 above - Summary of reported weather for MSL Sols 8 to 33. Figure 2 below - Original and revised MSL weather reports for September 5 and 6, 2012.
On page 156 of the book Magdy Bareh, electrical and computer engineer for MSL troubleshooting, discusses the problem:
Why didn’t it shut down? Bareh asked himself more than once. Yet the inability to shut down wasn’t the big problem, it was not knowing why it was happening that was worrisome.
How can we trust this computer?
Well, we can’t.
Sol 200 was on my radar screen two years before I read the above remarks by Bareh. As is shown on Figure 3, the pressure first report for that day was 937 hPa. That was higher than the highest pressure ever claimed by the REMS Team and JPL after it revised its data. The revised data showed a maximum pressure of 925 hPa that occurred on MSL Sols 170 and 171 (Ls 252 to 253 in MSL Year 1) and again on MSL 846 at Ls 257 in MSL Year 2. What Bareh seems to have addressed is a problem that came to his attention on February 27, 2013 via data downloaded at 10 am with a strange warning that involved several bits, the smallest measure of computer information. The errors were associated with a failure of Curiosity to send higher-level data to JPL correctly, although low-level telemetry. While Chapter 8 of Mars up Close does an adequate job of describing how they analyzed the problem and supposedly overcame it by putting the main computer into isolation and activating a backup computer, an unaddressed issue is why did the weather data for Sol 200 look so much like that on Sol 192? The pressure first given for Sol 192 was 940 Pa - 3 Pa higher than Sol 200. JPL changed both pressures to N/A. While high air temperatures for that time (summer began in Sol 197) were running between freezing and about -5°C, for Sol 192 it was -16°C, and for Sol 200 it was -21°C. A check of the REMS weather data site now indicates that JPL lists all weather data for these two sols as "Value not available," although they do indicate that both sols were sunny. However, through at least the first 1,077 sols (August 17, 2015), they never listed the sky condition as anything but sunny (despite UV values varying from very high to low). The original data posted offered minimum air temperatures of -68°C for both sols 192 and 200. There is reason to question whether all the weather instruments were malfunctioning on Sol 192 for the same reason that they did on Sol 200. Of course, JPL published 100% false wind data from August 6, 2012 until April 2013 when I nagged JPL's PR man Guy Webster to change all the wind data to N/A. Webster had admitted to me that the wind instrumentation broke of landing (this was well known). Two days after we spoke the wind data was pulled down and replaced with N/A.
Figure 3 - Summary of reported weather for MSL Sols 169 to 200.
Figure 4 shows a graph of maximum and minimum air and ground temperatures up through Sol 200. JPL states that, “A change in the pattern just after Sol 120 corresponds to Curiosity driving onto a type of ground with higher thermal inertia -- thus cooling off more slowly in the evening and warming up more slowly in the morning. The higher thermal inertia of this area was predicted from orbitistortal infrared measurements and is likely due to greater abundance of exposed bedrock relative to soil or sand.” However, in looking at the (revised) REMS weather reports available on August 19, 2015, I see that the entire weather report for Sol 200 now is NOT AVAILABLE. In fact, original pressure values between sols 192 and 200 were originally as high as 940 and 937 Pa and as low as 886 Pa, but all three pressures were changed to N/A. In fact, the revised weather shows all data as N/A from Sol 200 through 222. There was a weather report originally issued for Sol 215 after JPL noticed that the minimum air temperature was a relatively very warm -28º C (-18.4º F) they again pulled the weather data for the day and listed it all as N/A. This is the very real pattern that is seen again and again. Anytime the numbers do not fit JPL expectations they alter or distort the data or pull it all and list it as N/A.
Figure 4 - Maximum and minimum air and ground temperature up to Sol MSL 200. Image credit: NASA/JPL-Caltech/CAB(CSIC-INTA)/FMI/Ashima Research.