MALAPERT MOUNTAIN REVISITED

Burton L. Sharpe[1] and David G. Schrunk[2]

                ABSTRACT This paper describes a place - "Malapert Mountain" - in the South Polar region of the Moon whose physical features and location make it highly promising as a strategic site for the next stage of lunar exploration.  The paper is an update of the authors' previous paper on the same subject, and significantly refines, corrects, and expands pertinent prior data. 

                INTRODUCTION A prominent mountain ("Malapert Mountain") in the south polar region of the Moon has features that are very attractive for the next stage of lunar exploration and lunar base development. The present paper reports the results of reinterpreted radar-based topographical data.  It is concluded that the mountain has high strategic value as a site from which to begin and to coordinate the exploration of the south polar region of the Moon. 

                MALAPERT MOUNTAIN Malapert Mountain is located at 0° Longitude, 86° South Latitude in the south polar region of the Moon (Figures 1 and 2). It was previously reported (9) that the summit of the mountain has an altitude of 8000 meters (3).  Although the distance from portions of the base of the mountain to the summit are approximately 8000 meters, interpretations of Earth-based radar imaging data indicate that the summit of the mountain projects approximately 5000 meters above the reference surface ellipsoid of the Moon (4). The difference in these elevations is explained by the fact that imaged portions of the base of the mountain are below the reference surface ellipsoid of the Moon. The location of the mountain and elevation of the summit are attractive for the next stage of lunar exploration for four reasons: 1) Abundance of sunlight, 2) Earth visibility, 3) Access to scientific points of interest, and 4) Logistical and operational advantages for lunar science and engineering projects. 

Figure 1. Combined Clementine mosaic and Earth-based radar image of the south polar region of the Moon.  The subject mountain is located at 0° Longitude and 86° South Latitude is highlighted (NASA). 

Figure 2.  Blow-up image of the subject mountain in Figure 1 (NASA).  

Abundant Sunlight  Access to sunlight is critical for lunar activities because sunlight is needed for the generation of electric power (with solar panels) and for other energy management systems.  By virtue of its location near the South Pole and its 5000-meter elevation, the summit of the mountain receives less than full sunlight for only 11% of the time, which is far greater than non-polar regions that receive less than full sunlight 50 % of the time. The long duration of sunlight at Malapert Mountain thus makes it a very attractive site for lunar base activities.  Table 1 lists the projected sunset / sunrise events over the course of the lunar year at the summit of Malapert Mountain. 

Table 1.  Schedule of sunset / sunrise events at Malapert Mountain The table projects the number of hours that the sun passes below the horizon during the year 2005 at lunar 0⁰ Longitude, 86⁰ South Latitude, and 5000 meter elevation.  Every year is different, but most years have about 6 sunsets of similar duration, followed by 5-6 months of full sun.  For 2005, the summit of Malapert Mountain is projected to receive full or partial sunlight for 93% of the time.

Earth Visibility The second advantage is that the summit of Malapert Mountain is always in direct line of sight with the Earth for uninterrupted real-time control of robotic devices (a virtual presence for Earth-based operators) on the lunar surface. Figure 3 illustrates the locus of Earth's libration motions as seen from the summit over a one-year period (5); the entire disk of the Earth is always above the horizon, allowing for direct Earth-Moon communications 24 hours per day every day.

Figure 3.  Locus of Earth's libration motion for the year 2005.  For any given location on the Moon, the Earth's libration pattern with respect to the Moon is fixed.  From a location at the mountain's summit, the bottom of the libration box is approx. ½ degree above lunar horizon.  The field of view for this figure is about 60^o by 40^o and for the libration box is about 12^o by 14^o. The always-visible Earth above the lunar horizon means that continuous real-time communications between the Earth and the Moon are possible.

Other high elevations in the south polar region also have the Earth in view continuously and receive long periods of sunlight, and they may be considered as sites for lunar bases.  For example, two potential base sites at 84.5⁰ South Latitude, 39⁰ East Longitude and 83.5⁰ South Latitude, 38⁰ West Longitude have the Earth in view continuously and receive less than full sunlight for 15% and 24% of the year, respectively, as shown in Table 2. However, the combination of Earth visibility and long duration of sunlight strongly favors Malapert Mountain over other candidate locations as the first site for the next stage of lunar exploration.

                Table 2.  Sunset events of other potential lunar base sites located at 84.5⁰ South Latitude, 39⁰ East Longitude and 83.5⁰ South Latitude, 38⁰ West Longitude.

Science Opportunities Malapert Mountain may be considered as a prime candidate for the establishment of the first scientific base on the Moon.  Long periods of sunlight and a continuous communication link with the Earth, as exist at Malapert Mountain, are highly advantageous for conducting scientific and exploratory missions (2, 8). (A mission to Malapert Mountain would also provide information about the precise altitude of the mountain and the profile of the horizon as seen from the summit). Interpretations of data indicate that the rim of Shackleton Crater, which is located at the geographic South Pole, is visible from the summit at a distance of 122-Km (76-Mi.).  Thus, the mountain could become the center of communications and power generation (and power beaming / energy management) for exploratory missions to the South Pole and surrounding regions.

Malapert Mountain is located near areas that may contain water ice, as suggested by the Clementine and Lunar Prospector Satellite Missions (1). If the presence of water ice is confirmed, lunar base development will be greatly facilitated because water and its hydrogen and oxygen components will be needed for a host of lunar industrial / scientific processes and for biological systems. The areas at the base of the mountain are well suited for the operation of telescopes, particularly radio telescopes that can be shielded from the radio noise of the Earth and infrared telescopes that are placed on the low-temperature floors of permanently shadowed craters. The difference between the sunlit and shadowed areas of the mountain will permit experiments with circumferential utilities (just below the summit) (6), and long periods of sunlight can be applied to in-situ resource utilization experiments (7).

Logistics Advantages The fourth advantage is that the topography of the mountain renders it suitable for initial and follow-on missions. Existing navigation technology will enable automated supply missions to target, maneuver, and land at the mountain's summit, where, by inspection, there appears to be roughly ten square kilometers of area that is suitable for logistical operations. Also, the slope of the mountain to the northwest is less than 10⁰, which would allow wheeled vehicles to egress the mountain on treks to other areas in the south polar region, and return (see Figure 4). The summit is also the logical point (the high ground) from which to coordinate and support the growth of bases throughout the south polar region. 

Figure 4.  Downslopes away from the summit.  The slope to the West-North-West from the summit is less than 10⁰, which can be easily traversed with existing robotic systems. 

                SUMMARY Malapert mountain has unique and operationally optimum features that are advantageous for the next stage of lunar exploration. A direct, high bandwidth communication link with the Earth for continuous, real-time control of devices is possible from its summit, and long periods of sunlight are available for the operation of energy systems.  The mountain is suitable as a strategic base from which to conduct scientific and exploratory missions throughout the entire south polar region. From the standpoint of mission planning, the Malapert Mountain offers unique opportunities for the future exploration and development of the Moon. 

REFERENCES

1.        Binder, A.B., "Lunar Prospector: Overview".  Science Magazine, VOL 281, 4, pp 1475-76, September, 1998.

2.        Bussey, D., Spudis, P., and Robinson, M., 4"Illumination conditions at the lunar south pole."  Geophysical Research Leters, Vol. 26, No. 9, pp. 1187-1190, May 1, 1999. 

3.        Margot, J., Campbell, D., Jurgens, R., and Slade, M., "Lunar Topography: Preliminary Results".  Web site:   http://astrosun.tn.cornell.edu/students/margot/topography.html, 1999.

4.        Margot, J., personal email communication, 1-17-00.

5.        Maris Multimedia Ltd., Commercial Software, Redshift 2, San Rafael, CA, copyright, 1995.  (The Maris User's Guide states the software utilizes JPL ephemerides DE200 and DE102.) 

6.        Schrunk, D., Cooper, B., and Sharpe, B., "Concept for a permanent lunar utilities system".  Proceedings of the Fifth International Conference on Space '96, pp. 935-941, American Society of Civil Engineers, Reston, VA, 1996.

7.        Schrunk, D., Sharpe, B., Cooper, B., and Thangavelu, M., "The Moon:  Resources, Future Development, and Colonization".  Wiley-Praxis, New York and Chichester, England, 1999.

8.        Spudis, P., Stockstill, K., Ockels, W., and Kruijff, M., "Physical environment of the lunar south pole from CLEMENTINE data: Implications for future exploration of the Moon."  Lunar Planet. Sci XXVI, 1339-1340, 1995.

9.        Sharpe, B. L. and Schrunk, D. G., "An operationally ideal location for the first permanent base on the Moon". Proceedings of the Seventh International Conference on Space 2000, pp. 935-941, American Society of Civil Engineers, Reston, VA, 2000.