Mars Correct Basic Report Sections 15.6.1 to 15.6.3
Temperature sensor failures, personnel, and questions about pressure sensor range & sensitivity. Updated 9/20/2018.
15.6.1 Failure of the Temperature Sensor.
The right question is likely not about why the ground temperature sensor began to fail in March, 2017. Rather, it’s why NASA, or the REMS Team working for them, are allowing us now to see that there is something radically wrong with the sensor. The answer is likely very simple. Few people in the world care enough about Martian weather to inspire NASA to care. However, those that do are in many cases middle-level NASA workers who know something’s wrong, but are afraid to say something because it would cost them their job. I live in Cape Canaveral, Florida. Most of my neighbors who are not yet retired largely meet this description.
As I wrote earlier, Boom 1 that carried the ground temperature sensor was damaged on landing in 2012. It took about 9 months before the REMS Team began to publish any ground temperatures at all in their daily weather reports. Then 9 months’ worth of ground temperature data suddenly appeared, along with a statement by Guy Webster that only the wind sensor on the boom was destroyed (we got him to remove all wind data). In July, 2013 NASA decided to revise a lot of air temperatures way down, dropping many from above freezing to well below it - see Table 20 in Section 15 of this report.
Perhaps the most important thing for our readers to understand is that not all NASA data published by NASA is from NASA alone. In an astonishing twist of fate, much of it in part actually originated here. How is that possible? Look at our records for MSL Sol 1605 (Ls 314, February 10, 2017). See Figure 83 and Annex V of this report. The REMS Team originally published a pressure of 815 Pa, but the preceding day the pressure was 850 Pa. A drop of 35 Pa was not reasonable from one sol to the next. Typically the change in pressure is under 10 Pa. So we predicted that NASA would alter it, and they did indeed back up to 847 Pa. When this happens we don’t just put it on our weather spreadsheets. We document the prediction and NASA changes by publishing before and after print-screen showing what NASA did.
For Sol 1605 (February 10, 2017) we also successfully predicted that NASA would alter its temperature data. At first they published a low air temperature of -54° C. We noted that the previous sol (1604) had an air temperature low of -77 ° C. Such large changes from one sol to another have not survived in the past (that is, before about March 18, 2017. Sure enough, NASA altered the air temperature low for Sol 1605 to -73 ° C. Likewise, the initial ground temperatures for Sol 1605 were +10 ° C for a high and -61° C for a low. For Sol 1604 they were +15° C and -77° C. That was too much of a change, so NASA made the predicted change and claimed Sol 1605 ground temperatures were really +14 and -78° C. This cat and mouse game has gone on for five years now, and we have documented it all. NASA seems to have had one agenda only – keep the data on a believable curve, and hope that nobody with access to the purse strings figures out what they have been doing. However, for some reason, this pattern was altered around Sol 1640 (March 18, 2017). The question is, why?
15.6.2 Personnel Issues.
The inventor of the pressure sensor, Henrik Kahanpää of the Finnish Meteorological Institute and of the REMS Team is a frequent visitor of our three websites. So are other REMS Team members. Given the loss of the ExoMars 2016, likely due to bad weather data from NASA, we suspect that major (European) Mars weather personnel have had enough of pressure to conform.
Figure 83 - After we posted the three images on the left someone at the REMS Team or at JPL altered the Sol 1605 report to what is shown on the right. It is quite apparent that before March, 2017 reports that vary too much from the preceding day or previous Martian year at the same Ls do not survive long at the REMS site at http://cab.inta-csic.es/rems/en.
15.6.3 Mixed messages about the range and sensitivity of pressure sensors sent to Mars.
It has on been our position that NASA has understated Martian pressure by two orders of magnitude. On Figure 57 we made a case for a pressure at areoid of about 511 mbar (vs. the accepted pressure of 6.1mbar), at Mars Pathfinder of ~719 mbar, at MSL ~768 mbar, at the Valles Marineris 835 mbar and in the Hellas Basis about 1,054 mbar (more than average pressure of 1,013.25 mbar at sea level on Earth). While mbar are the pressure units that we most prefer, others in the scientific community use pascals (Pa) or hectopascals (hPa). We have often noted mistakes in publication where hPa are confused with Pa and vice versa. The difference between these units is two orders of magnitude (i.e., two decimal places).
The problem first came to our attention when we found that the REMS Team originally published pressures ranging from 737 to 747 hPa between August 30, 2012 and September 5, 2017. On September 2, 2012 we called Guy Webster, the PR man at JPL, and told him that if these pressures were correct, he needed to parade out the President of the United States to announce the greatest discovery in astronomy – that Mars has air pressure like than on Earth. On September 5, 2012 REMS said the pressure was 747 hPa (i.e., 747 mbar). The next day they published a pressure of 747 Pa (i.e. 7.47 mbar). This was captured by print-screen on Figure 17A. Soon after that they changed all the high pressures, rolling them back from hPa to Pa. Was this a simple accident?
We have worked for nine years with Viking 1 and 2 data taken from "Mars Meteorology Data; Viking Lander." Mars Meteorology Data; Viking Lander. N.p., n.d. Web. 10 Feb. 2015. This is found at http://www-k12.atmos.washington.edu/k12/resources/mars_data-information/data.html. On July 12, 2017 we received an e-mail from an engineer by the name of Nathan Mariels, CEO at Global Electric Technology. In it he wrote:
Pa is not equal to hPa. From Viking logs: "Pressure mb = millibars, 1 mb = 100 hPa, where hPa = hecta Pascals" This is incorrect. 1 mb = 1 hPa = 100 Pa.
The above error was repeated on every data set for Viking 1 and 2. A sample is captured by print-screen on Figure 84.
Nathan found similar errors on MSL data that he examined. He also found different pressure ranges for landers than what we found, although we noted on Figures 10A and 10B that three of four sensor ordered by NASA from Tavis were rated for maximum pressures under 25 mbar, one of them – Tavis Dash Number 1 was rated at 15 PSIA which converts to 1,034 mbar. Pathfinder pressure problems were discussed earlier in Section 12 of this report. The Vikings and Pathfinder all used Tavis pressure transducers which are discussed in great detail in Annex G of this report (http://marscorrect.com/ANNEX%20G%2010%20September%202013.pdf). While it seems hard to believe that a mere copying over of wrong units from one page to another caused serious problems, that’s what might have happened with all of the Viking 1 and 2 data at http://www-k12.atmos.washington.edu/k12/resources/mars_data-information/data.html.
The problem with accepting the accident explanation for the Vikings is that it still leaves us with an order in 1976 by Dr. James Fletcher to manually alter the color of the Martian sky on all JPL monitors, and it leaves us with 36 years of altered sky color until we were finally permitted to see blue sky at Gale Crater, Mars in 2012.
Figure 84 Viking 1 and Viking 2 error in unit conversion.
Now, let’s look at another problem brought to my attention by Nathan – an inconsistency with respect to the pressure range and sensitivity on MSL. In particular, let’s look at the Abstract put out by the Finnish Meteorological Institute, which created the pressure sensors on Phoenix and MSL.
First let's examine a statement that backs the 1150 Pa figure: In Section 11 of the REMS Calibration Plan (Document No, CAB-REMS-PLN-002, Issue 002, it states:
REMS shall measure the Ambient Pressure in the range of 1 to 1150Pa with a resolution of 0.5 Pa and accuracy of 10 Pa BOL and 20 Pa EOL. Requirement 012 (PLD-20), REMS shall measure the Ambient Pressure at a minimum sampling rate of 1 Hz for at least 5 minutes each hour continuously over the mission.
The pressure device measurement range is 0 - 1025 hPa in temperature range of -45°C - 55°C, but its calibration is optimized for the Martian pressure range of 4 - 12 hPa.
Note: 1025 hPa = 1,025 mbar. So, while it was supposedly optimized for 4 to 12 (not 11.5 mbar – meaning that the problem is not one of a sliding decimal place), it was still capable of measuring up to 1,025 mbar. Again, average pressure on Earth at sea level is 1,013.25 mbar. This is, to borrow a phrase from the Wizard of Oz, a horse of a different color. For the record, we have preserved the FMI abstract showing the 1,025 mbar capacity with the print-screen on Figure 86. As for the temperature range, at MSL there were no reports of low temperatures as warm as -45°C that were not changed to much colder temperatures. For example, there was an air temperature low of -46°C reported by the REMS Team for Sol 880 on January 27, 2014, but they altered it after we highlighted it on our REMS data spreadsheets at http://marscorrect.com/photo4_11.html and in particular the print-screen record seen below as Figure 85. Note: As was shown on Table 15b earlier, during the Global Dust Storm of 2018 the warmest low for air temperature was -58°C on Sol 2103, and the warmest low for ground temperature was -56°C on Sol 2085.
Figure 85 The REMS Team would not permit low temperatures warmer than -50°C.
Figure 86 Print-screen (recorded on July 23, 2017) of the FMI Abstract entitled Pressure and Humidity Measurements at the MSL Landing Site Supported by Modeling of the Atmospheric Conditions.
Figure 87 - The Vaisala Pressure sensor and its range as depicted by Spaceflight101.com.
On July 24, 2017 we found that the REMS Team again altered the maximum pressure to 1400 Pa (14 mbar). See Figure 88. After they raised the maximum pressure from 1150 to 1400 Pa, they published a maximum pressure of 1,294 Pa for Sol 1784 on August 13, 2017. On the previous sol (1783) the pressure published was only 879 Pa. Yet even with the newer (likely false) upper pressure range of 1,400 Pa, when we challenged it with our colored spreadsheet and print-screen (http://davidaroffman.com/photo5_15.html), the REMS Team dropped the 1,294 Pa for that sol to 883 Pa.
Figure 88 REMS puts out a new maximum pressure for MSL. This time its 1400 Pa (14 mbar). Here they also claim a relative accuracy (repeatability in the time scale of hours) of less than 2 PA and a resolution of 0.2 Pa. On Figure 71 the resolution was 0.5 Pa.