Higher than Advertised Martian Air Pressure: Part 4
By David A. Roffman and Barry S. Roffman (Updated 10/31/2012)
2.5.2. The issue of daily pressure spikes at consistent time-bins.
A large pressure increase rate at the same time every day would be consistent with a limited amount of Martian air trapped behind a clogged dust filter or pressure equalization port. As was shown on Table 2 and Figure 7, there were multiple such hikes found in the audit of the Viking Project Group data.
Data was divided into 25 bins per sol, each about 59 minutes. The 0.26 to 0.30 time-bin should be an appropriate time to make RTG heat available and to turn on equipment. If air were trapped at the transducer, it would be expected that at the transducer pressure would increase rapidly then. Figures 14A to 14F and Annex A show that this happened for VL-1 starting around its Sol 108 Ls 149 (late summer) until the last data posted at its Sol 350 in winter (Ls 297). Likewise for VL-2, there was almost always a pressure increase in the .26 to .3 time-bin after the summer.
For VL-1 in the 333 days examined, pressure only decreased 5 times in this time bin (4 of these in the early summer before Sol 108, with none then more than 0.02 mbar, and the 5th case was just 0.03 mbar on sol 240, Ls 227.084). All of these 5 exceptions were for amounts less than the 0.08 to 0.09 accuracies allowed by digitization of pressure data described above. For VL-2 over 206 sols specified, pressure only decreased twice, each time just .01 mbar. The next time-bin (0.3-0.34) showed a much more varied pattern. Red lines show the first time-bin and blue show the second time-bins on Figures 14A-14K.
2.6. Initial Mars Science Laboratory Pressures.
The MSL Remote Environmental Monitoring Station team initially put out a lot of bad information at http://cab.inta-csic.es/rems/marsweather.html. It went from listing the pressure on August 28, 2012 as 7.4 hPA (mbar) and the month as 3 when it was really month 6; to a pressure of 742 hPa (Earth-like, seen in much of the U.S. West every day) in month 3 to 747 Pa (which equals 7.47hPa/mbar). See Figure 17. The 7.4 hPa range was totally consistent with Figure 18 offered later in this report, but that does not mean we accept it as correct. We do not. As stated earlier under Section 2.4, we expected that the same type sensor, delivered to JPL at the same time as Phoenix, would produce similar results. The reason that we are suspicious is that as was the case with the Vikings, there was an inverse relationship between daily pressure and temperature. This is shown below.
Figures 13A to D Below. Inverse relationship between MSL Sol 10 to 11 temperatures and pressures. Adapted from http://www.spaceflight101.com/msl-rems-science-reports.html.
3. CAVES ON AND SPIRAL CLOUDS ABOVE ARSIA MONS ON MARS.
Cushing and Wynne (2007) proposed that photos from the Mars Odyssey mission reveal football-field size holes (see top of Figure 15) that could be entrances to caves on Arsia Mons. The seven suspect caves ranged from 100 to 251 meters wide and 130 meters deep. The claim that they are caves is based on an analysis of photographs from the Thermal Emission Imaging System aboard NASA's Mars Odyssey orbiter. The dark spots do not look like impact craters since they lack raised rims or blast patterns. In 2012 JPL released a photo of a hole on Pavonis Mons, with the floor of a cavern visible about 20 meters below (see bottom of Figure 15).
The dust devil issue here is whether drafts rising from inside these caves on Arsia Mons could serve as the cause of the dust devils that are seen even at 17 km there. Temperatures in these features are warmer than the outside air at night and cooler during the day. Dust devils are not the only feature spiraling up from Arsia Mons. As seen on Figure 16, the Jet Propulsion Laboratory states that:
Just before southern winter begins (NOTE: This is in error, JPL should have indicated just before southern spring begins), sunlight warms the air on the slopes of the volcano. This air rises, bringing small amounts of dust with it. Eventually, the rising air converges over the volcano's caldera, the large, circular depression at its summit. The fine sediment blown up from the volcano's slopes coalesces into a spiraling cloud of dust that is thick enough to actually observe from orbit. The spiral dust cloud over Arsia Mons repeats each year, but observations and computer calculations indicate it can only form during a short period of time each year. Similar spiral clouds have not been seen over the other large Tharsis volcanoes, but other types of clouds have been seen... The spiral dust cloud over Arsia Mons can tower 15 to 30 kilometers (9 to 19 miles) above the volcano. (NASA/JPL/MSSS, 2005, PIA04294).
Figure 15 Below – Top: Seven black spots like the one above on Arsia Mons may be caves or just pits. Images were taken from the Thermal Emission Imaging System aboard NASA's Mars Odyssey orbiter (reproduced from http://www.areavoices.com/astrobob/images/Mars_possiblecave_entrance_on_Arsia_Mons.jpg)
Bottom: Opening to Pavonis Mons discovered in 2012. The floor of the cavern is ~20 meters deep. Source: http://hirise.lpl.arizona.edu/ESP_023531_1840