Tuesday, September 27, 2016

Mars: Part 1 Dust Particles

Dr. Robert Duncan-Enzmann

Image of Earth dust from: http://entropymag.org/on-dust/

Dust enters the atmosphere of Mars from outside the planet as meteorite debris and from the surface of Mars due to atmospheric forces. In the lower 10,000 feet of the atmosphere the suspended dust is almost exclusively of surface origin. Dust is subtracted from the atmosphere of Mars by gravitational forces. The removal of suspended matter from the atmosphere to form surface deposits is accelerated by: 1) surface friction; 2) coagulation of dust particles; 3) vapor condensation on dust; and 4) adhesion of dust to ice (H20?) crystals.

The spread of suspended dust through the atmosphere of Mars is limited to several factors: 1) the balance of forces tending to add and subtract dust described in the above paragraph; 2) vertical extent and size of turbulences in the immediate ground environment; 3) vertical extent and size of turbulences above the immediate ground environment; 4) mean wind velocities; 5) adherence of particles to the surface at contact and as a function of time. Turbulence, which may be measured by the size of eddies or vortices, dominates transport and mixing of dust in an atmosphere. Instead of molecular kinetics, as expressed by molecular viscosity, conductivity, and diffusivity, the spread of particles is described on the basis of eddy viscosity, eddy conductivity, and eddy diffusivity.

To estimate the amount of dust in the atmosphere, it is necessary to know the factors outlined above and also something about the surface. For strong mixing to occur between the immediate ground level and higher levels it is necessary to have major turbulence, as introduced by topographic interference. Source and sink areas should also be considered. In the Earth environment sources are land areas and sinks are oceans. In the Mars environment there seems to be nothing like standing bodies of water. Adherence of particles to the surface may be enhanced by polar cap materials; adherence of particles may be enhanced by dark areas which could represent moisture. Generally conditions seem to be those of a cold, relatively flat desert with little interstitial water at the surface. Such an environment would parallel the worst desert conditions of Earth, with little tendency for particles to adhere to each other over relatively vast areas.

Using the Kaplan atmosphere and estimates made by Vaucouleurs, dust per unit volume of atmosphere in the immediate surface environment and also through the troposphere should be within one order of magnitude of terrestrial conditions.

In conclusion, although total dust content per unit volume of the Mars atmosphere may approximate or even exceed that of the Earth’s atmosphere, it should not cause any difficulties in communications or erosion. The average wind velocity is low, perhaps 20 mph average in the Trade Wind Belt, precluding significant wind erosion in anything but geological times. The low wind velocity also suggests a low frequency for static noise due to dust impacting on uninsulated antenna.


(Stay tuned for Mars Dust Particles, part 2: Effects of Suspended Dust)


Dr. Robert Duncan-Enzmann, designer of the Enzmann Starship

physicist, scientist,  astronomer, geologist, archaeologist, historian, linguist, medical doctor

British Embassy School, Peking, China; Univ. London; WW II USN, AC; RN, AB Harvard; ScB Hon., London; Standard, MSc, Witwatersrand; Nat Sci Scholar; MIT course work; Royal Inst. Uppsala Swed.; PhD/MD Cuidad Juarez, Mex.; Pacific Radar: Greenland Gap-filler, Canada DEW-line; SAGE; Pacific PRESS; California ATLAS, BMEWS;  ICBM; Kwajalein Atoll ICBM intercept; TRADEX; Mars Voyager; Cryptography.

Thursday, September 8, 2016

Mars Part 2 Notes Concerning the Atmosphere of Mars



Notes concerning the atmosphere of Mars by Dr. Robert Duncan-Enzmann:

Wind profiles and velocities
Dust particles
Topographic considerations
Introduction to interactions with lithosphere and hydrosphere



Vertical Wind Profiles 

During the last 3 to 5 km of descent the capsule will be in the stratosphere and troposphere. It is possible that at certain times and locations – as is sometimes the case in terrestrial Polar locations – that the stratosphere of mares will be in direct contact with its surface, resulting in the local absence of a troposphere.
The following layers, which could strongly perturb descent, will be present in the last 3 to 5 km of descent regardless of whether the general zoning is tropospheric, stratospheric, or both:
1. horizontal cross winds with shearing as expressed by Helmholtz interference
2. surface turbulent channel extending from the surface to a minimum of 10 meters to a minimum of 300 meters above the surface
3. the so-called logarithmic layer a few centimeters above the surface
4. the major eddies associated with the topography
5. ground effect when the vehicle is a distance above surface on the order of its horizontal extent.

It is recommended that these features be examined for the amount of perturbance associated with each feather be studied. This can be done on the basis of maximum and minimum values. Sufficient information is available to yield such values, which in turn will indicate the maximum and minimum parameters for which the system will have to be built. 


The geographic distribution of winds, horizontal wind patterns, and the vertical profiles of winds should be considered in designating landing sites, and in designing landing mechanisms. Winds over the surface of Mars and to approximately 10,000 feet above the surface are estimated to move at relatively low velocities. The estimates have been made by observation of moving cloud patterns, observation of yellow dust cloud movements, computation from thermal gradients as a function of latitude, computations treating the planet as a black body, estimate of time necessary to transfer supposed water from the cold trap at one pole to the cold trap at the other pole. (13 Vaucouleurs) Observations and estimate indicate a rather low average wind velocity  perhaps 20 mph. Locally wind velocities may exceed this value.
Conditions indicating winds in excess of 20 mph are to be expected in association with the following features, which are listed in order of importance, the feature with the strongest winds first.

1. Sub-polar Spot: (Capricorn and Cancer) The heat capacity of the atmosphere about Mars is relatively low. Much heat is stored in the rocks of the surface, however, this is released quickly, therefore winds about the sub-polar spot may be expected to be strong. The writer estimates up to 80 mph.
2. Trade Wind Belt: Expected to be a zone of prevailing winds moving from east to west; these winds are positioned somewhat to the south of the geographic equator.
3. Westerly Belts: Zones of northern and southern westerlies seem to show more rapid movements of clouds and fronts than over an average area of the planet
4. Polar Easterlies: Zones in which winds moving from east to west may be expected to exceed average values.
5. Atmospheric Channels: Winds seem to be stronger over the dry hemisphere from long. 270˚ to long. 90˚ and on a lesser scale through the Pandorae-Fretum / Hellespontus structure.
6. Surface Thermal Anomalies: The areas of Noachis seems to show abnormal temperatures. It may be the reason for localization of cyclonic circulation and development of darkening in the Pandorae Fretum. It is located at long 350˚ and 360˚. The writer estimates on the basis of terrestrial differences between ambient winds and winds beneath such cloud structure, that winds could reach velocities of 300% above average in temporary gusts. 

Wind Profile Charts:





Stay tuned for the next section on Dust Particles


Dr. Robert Duncan-Enzmann, designer of the Enzmann Starship

physicist, scientist,  astronomer, geologist, archaeologist, historian, linguist, medical doctor


British Embassy School, Peking, China; Univ. London; WW II USN, AC; RN, AB Harvard; ScB Hon., London; Standard, MSc, Witwatersrand; Nat Sci Scholar; MIT course work; Royal Inst. Uppsala Swed.; PhD/MD Cuidad Juarez, Mex.; Pacific Radar: Greenland Gap-filler, Canada DEW-line; SAGE; Pacific PRESS; California ATLAS, BMEWS;  ICBM; Kwajalein Atoll ICBM intercept; TRADEX; Mars Voyager; Cryptography.