Potential Lunar Base on Mons Malapert: Topographic ...tain Mons Malapert (MM) near the South pole of the Moon is a key candidate for the location of such a base. MM is an ~30 × 50

ISSN 0038-0946, Solar System Research, 2019, Vol. 53, No. 5, pp. 383–398. © Pleiades Publishing, Inc., 2019.

Potential Lunar Base on Mons Malapert: Topographic,Geologic and Trafficability Considerations

A. T. Basilevskya, b, *, S. S. Krasilnikova, M. A. Ivanova, M. I. Malenkovc, G. G. Michaelb,T. Liud, J. W. Heade, D. R. Scotte, and L. Larke

aVernadsky Institute of Geochemistry and Analytical Chemistry, RAS, Moscow, 119991 RussiabPlanetary Sciences and Remote Sensing, Institute of Geological Sciences, Freie Universitaet Berlin, Berlin, 12249 Germany

cSpace Research Institute, Moscow, 117997 RussiadInstitute of Geodesy Geoinformation, Technische Universität Berlin, 10623 Germany

eDepartment of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, 02912 USA*e-mail: [email protected]

Received March 26, 2019; revised April 9, 2019; accepted April 29, 2019

Abstract—Polar areas of the Moon are prospective sites for construction of a lunar base due to the near con-stant illumination conditions and the potential presence of water ice in the regolith of cold traps. The moun-tain Mons Malapert (MM) near the South pole of the Moon is a key candidate for the location of such a base.MM is an ~30 × 50 km mountain elongated in a WNW-ESE direction with a NNE extension. Its summitstands ~5 km above the 1838 km datum, has constant visibility from Earth and long periods of sunlight (87 to91% of the year). In this analysis we consider the topographic, geologic and trafficability characteristics ofMons Malapert, which need to be taken into account in the further consideration of MM as a lunar base loca-tion. The topography and its derivatives were studied using LROC WAC images and the LOLA-based DTM.South of MM lie the ~50 km craters Haworth and Shoemaker whose f loors are in permanent shadow andshow a neutron spectrometric signature of high water-ice content that may be a source of water for the base.The geology of the MM region is defined by its position on the rim of the South-Pole-Aitken basin, the larg-est and most ancient impact basin on the Moon. The ancient age of this area is confirmed by crater spatialdensity which shows ages of ~4.2 Ga. The MM slopes are mostly rather steep: from ~20 to 30°, while slopeson its summit and base are more gentle. LROC NAC images of this area show that while the summit and baseof MM are covered by numerous small craters, its steep slopes show a deficit of craters and are complicatedby low ridges appoximately perpendicular to the downslope direction. These characteristics of the steepslopes suggest effective downslope movement of the regolith material that, in turn, suggests that the mechan-ical properties of the surface layer here are relatively weak. The siting, building and operation of a lunar baseimplies activity not only in-base and close proximity, but also traversing to other distant sites of interest forresources and scientific investigations. So planning the Mons Malapert base requires the detailed analysis ofthe trafficability of the region. To consider this issue we return to experience gained by the operations ofSoviet Lunokhod 1, 2 and the US Apollo Lunar Roving Vehicles. On the basis of new and evolving technol-ogy, rovers designed for the MM lunar base may significantly differ from earlier rovers, but consideration oftrafficability of the earlier rovers is important for future planning. Our analysis shows that neither Lunokhods northe Apollo LRV could successfully climb most of the slopes of Mons Malapert. The acceptable trafficabilityappears to be only possible along the WNW crest of the mountain. For emergency cases wheel-walking rovers maybe considered. Mons Malapert seems to be a good locality for the lunar base but more studies are needed.

DOI: 10.1134/S0038094619050022

INTRODUCTIONPolar areas of the Moon are candidates for the con-

struction of a lunar base (e.g., Burke, 1985; Zelenyi,2016). Their obvious advantage is the presence ofwater ice in the regolith of so-called cold traps (e.g.,Feldman et al., 1998, Colaprete et al., 2010; Saninet al., 2017). Water is a valuable resource for basic crewlife support and a source of oxygen for life as well asoxygen and hydrogen as fuel components. Besides,polar areas outside the cold traps are rather climati-

cally comfortable because of the absence of very highmidday temperatures typical for a majority of lunarregions. As shown by measurements by the DivinerLunar Radiometer Experiment, the midday surfacetemperatures in the polar areas outside of shadows aremostly in the range of 150 to 220 K (Paige et al., 2010,their Fig. 1).

The mountain Mons Malapert (unofficial name) isconsidered as one of places to build the base in thepolar area of the Moon, near the lunar South pole

383

384 BASILEVSKY et al.

Fig. 1. (a) Part of LROC WAC mosaic of the South pole of the Moon 60°–90° S, zero meridian is in the image top, projectionpolar stereographic, arrow shows location of Mons Malapert. (b) Part of the WAC mosaic showing Mons Malapert. (c) The sameimage showing positions of the LROC NAC images used in this study.

M172956767LEM172956767LE M172949982LEM172949982LE

M170615049LEM170615049LE

M135795356LEM135795356LE

M137538218LEM137538218LE50 km

(a)

(b) (c)

M172956767LE M172949982LE

M170615049LE

M135795356LE

M137538218LEM1226378282RE

(e.g., Sharpe and Schrunk, 2003; Cooper and Simon,2007, Fig. 1).

This mountain is located at about 86° S, 0° E andits summit stands ~5 km above the 1838 km datum. Itis in constant visibility from Earth a factor that isimportant for direct communication links. Anotherimportant characteristic of MM is that it has long periodsof sunlight (87 to 91% throughout the lunar year), afactor that is critical for solar-electric energy produc-tion. Since the time of the earliest suggestions to buildthe base on Mons Malapert, study has continued (seefor example, “Bedford Astronomy Club” LunarBase, April 16, 2017, https://www.astronomyclub.xyz/lunar-base/mons-malapert.html). The Russian privatecompany Lin Industrial, currently developing theultralight weight Taimyr rocket, also suggests to con-sider Malapert Mons as a place for a lunar base(https://www.newsmax.com/newsfront/lin-industries-moon-base-rare-earth-elements/2014/12/31/id/615873/).

In the present paper we synthesize and discuss thetopographic, geologic and trafficability characteristicsof Mons Malapert, all of which need to be taken intoaccount in further consideration of this locality as alunar base. Our analysis of the characteristics of Mala-pert Mons to some degree overlaps with the analysispresented in Allender et al. (2019). That work exploresan architecture of a Design Reference Mission thatfocuses on the exploration of the south polar region ofthe Moon by sequential visits to five landing sites (oneof which is Mons Malapert) beginning in 2028. Themission will use a reusable lander, two rovers carryingtwo astronauts each in the landing area. They willstudy the area, take samples and then return to theorbital module. Meanwhile, the rovers are tele-robot-ically driven to the next landing site. It is not yet clearwhether that or other missions of that scale will takeplace prior the construction of lunar base(s).

SOLAR SYSTEM RESEARCH Vol. 53 No. 5 2019

POTENTIAL LUNAR BASE ON MONS MALAPERT 385

TOPOGRAPHY AND ITS DERIVATIVES

Mons Malapert topography and its derivatives werestudied using LROC WAC images and the LOLA-based DTM LDEM80S20M_a1 with spatial resolu-tion of 20 m (Fig. 2).

It is seen in Figs. 2a, 2b and 2c that Mons Malapertis an ~30 × 50 km mountain elongated in a WNW-ESE direction and having a NNE extension. Its sum-mit is about 5 km above the datum. Its slopes arelocally rather steep (up to 20°–30°, Fig. 2d) and theconsequences of this are discussed later. South ofMalapert Monsthere is the 51-km crater Haworth andthe 52-km crater Shoemaker (Tye et al., 2015) whosefloors are in permanent shadow (Fig. 2e) and show aneutron spectrometric signature suggesting significantwater ice content (Fig. 2f; Sanin et al., 2017).These cra-ters may be interesting as a source of water for the poten-tial Malapert base. Figure 2e also shows that the narrowsummit region of Mons Malapert is illuminated by theSun for a very long time, an advantage of this place.

GENERAL GEOLOGY OF THE MONS MALAPERT AREA

Mons Malapert represents a large segment of theancient terrain of pre-Nectarian age, unit pNbm(basin massif material), which was interpreted as partsof the South Pole – Aitken (SPA) basin rim (Wilhelmset al., 1979). The multiple occurrences of this unitform elongated chains of elevated and steep-sidedmassif-like blocks along the major topographic stepthat separates the low-lying f loor of the SPA basin andits elevated rim (Garrick-Bethell and Zuber, 2009). Inthe geological map of the southern hemisphere of theMoon (Wilhelms et al., 1979), the approximate posi-tion of the SPA rim was shown as a line connecting theoccurrences of the unit pNbm that appear as a series ofthe high-standing massifs unrelated to the populationof ancient impact craters. The inferred location of theSPA rim was northward of Mons Malapert (Fig. 3).

Later, the location of the SPA rim was reconsidered(Garrick-Bethell and Zuber, 2009) on the basis of thehigher-resolution topographic data from the Clemen-tine mission (Zuber et al., 1994) and the shape of theFeO and Th anomalies inside the SPA basin detectedby the Lunar Prospector mission (Lawrence et al.,2002, 2003). In their work, Garrick-Bethell and Zuber(2009) have approximated the outermost rim of theSPA basin by an ellipse with the ~2400 km long axisoriented along the 170° E meridian. The ellipse runsthrough the high-standing massifs (including MonsMalapert) that occur at the inner edge of the SPA rim(Fig. 3). The rim of an impact structure of the scale ofSPA, however, cannot be approximated exactly by asingle line but rather represents a broad (several hun-dred kilometers wide) zone as it is seen in the northernportion of the SPA basin (Ivanov et al., 2018). Thus,the location of the SPA rim inferred either from mor-


phology (Wilhelms et al., 1979) or from the topo-graphic and compositional characteristics (Garrick-Bethell and Zuber, 2009) likely corresponds to differ-ent portions of the same structure. Mons Malapertcertainly is a part of the rim and represents an expo-sure of the ancient lunar crust and SPA ejecta thatexisted prior to the SPA impact event. Results of ourphoto geologic analysis of the Mons Malapert area arepresented in Fig. 4a.

The geologic map (Fig. 4a) generally follows thelunar stratigraphy of Wilhelms (1987) and illustratesthat the majority of the study area is occupied by thePre-Nectarian unit (pNc), which is intrpreted to be amixture of fragmental and impact-melt breccias. Anddescribed above, Malapert Mons and a few other fea-tures in this area are interpreted to be remnants ofejecta of the South Pole-Aitken basin (SPA in Fig. 4a),considered to be the most ancient detectable impactbasin and thus among the oldest available material onthe Moon text in parentheses should be deleted.Therefore, analyses undertaken during geologic excur-sions in this region are very ikely to return fundamen-tal and unique knowledge about the very beginning ofthe geologic history of the Moon. Several craters withdiameters of several dozen km, and their ejecta, aresuperposed on SPA units and pNc, and form the Nec-tarian unit Nc. Several similarly-sized craters aresuperposed on units pNc and Nc, and form the Imbrianunit Ic. Several craters morphologically more prominentthat those of Nectarian and Imbriam age and their ejectawere mapped as Eratosthenian unit Ec. In addition, a fewcrater clusters considered as relatively young secondarieswere mapped: unit Sc. Finally, a few occurrences ofintercrater plains were mapped (unit Icp) whose nature isnot clear; they are likely to be deposits of crater ejecta. Insummary, the major process forming and modifying theobserved surface morphology is impact cratering. Asdescribed above, the most interesting goal for explora-tion and analysis in human and robotic geologic excur-sions in the region are the SPA unit outcrops, and mostconvenient of these is Mons Malapert.

The Pre-Nectarian age of a significant part of thestudy area is supported by crater counts that we under-took (Fig. 4b), which indicate an age of ~4.2 Ga. Thisis the mean age estimate for the area which containsseveral geologic units, ages of which according to theresults of geologic mapping vary from Pre-Nectarianthrough Nectarian, Imbrian, and Erathosthenianextending to Copernican.

As described above, the units mapped as Pre-Nec-tarian and SPA make up the majority of the region,with those mapped as Nectarian, Imbrian and Eratos-thenian being exclusively comprised of superposedcraters and their ejecta. There being no identified non-impact-produced units prior to the Copernicanperiod, it makes sense not to exclude these in trying todate the region. Some Copernican mapped unitsthemselves are interior to older craters, making them

386


BASILEVSKY et al.

Fig. 2. The 200 × 200 km study area centered o Mons Malapert. (a) LROC WAC image; (b) shaded relief; (c) color-coded topog-raphy; (d) map of slopes; (e) average solar illumination in time percent (from the LOLA-based AVGVISIB_75S_120M_201608);(f) shaded relief map with water equivalent superposed (bluish tone). The top dry layer thickness is assumed to be 40 cm. “H” inpart (a) shows crater Haworth and Sh shows crater Shoemaker.

50 km50 km

(a)(a)

(c)(c) (d)(d)

(e)(e) (f)(f)

(b)(b)

H

ShSh

50 km

(a)

(c) (d)

(e) (f)

(b)

H

Sh

ElevationHigh: Slope, deg

0 0.5

H2O, wt %

Low:

+6799 m

−5037 m

0−5

100

80

60

40

20

0

5−88−1010−15

15−2020−2222−2626−3030−79


Fig. 3. Location of the SPA rim inferred from regional morphology (Wilhelms et al., 1979) and topography (Garrick-Bethell andZuber, 2009). The massif of Mons Malapert is at the inner edge of the major topographic step that separates the rim and f loordomains of the SPA basin. The image is a mosaic of the WAC images (100 m/px resolution) overlain by LOLA gridded topography(1/64 px/deg.resolution); contour interval is 2 km. Polar stereographic projection.

100 km100 km100 km

Mons Malapert

SPA rim, Wilhelms et al., 1979

SPA rim, Garrick-Bethell and Zuber, 2009

0 km4 km

2 km

�2 km

�4 km

irrelevant to crater counts at lesser scales (Kneisslet al., 2016); the remainder are low-relief deposits inlow-lying areas, which would not be expected toobscure and bury the topography of the larger cratersthat are most significant to an age determination of theregion. On this basis, we find an age of ~4.2 Ga in theNeukum (1983) chronology system.

Four distinct units which could be encounteredduring explorations in the direct vicinity of MalapertMons were dated by crater counting methods using theNeukum (1983) chronology system (Fig. 5). The firstarea is a region near the peak of the mountain (marked b)which shows a significant crater population. Stronglyinclined slopes tend to retain few impact cratersbecause of the loss through mass wasting (e.g., Basile-vsky, 1976, Fig. 5) which may, in particular, beinduced by impacts themselves. Thus the populationhere is unlikely to be representative of anything morethan the crater retention time in the region. We makeno attempt to identify the timing of any particularevent from the data, but note that the larger craters ofthe population (>800 m diameter) approach andexceed the isochron at 3.85 Ga, suggesting that thissurface, at least, has not been subject to significantmass wasting since then.

Secondly, we dated the ejecta of two nearby largecraters of 8 and 20 km diameter (marked c, d). Thesmaller one, directly at the foot of the region of theshallowest descent from the mountain, was estimatedto be Ga old, and the larger one to the north to

be Ga. Using the Neukum (1983) chronology

+−

0.30.3~1.7

+−

0.30.3~2.3


system, we estimate that craters exceeding 8 km diam-eter are expected to form, on average, once every43 Ma on the Moon, and those of 20 km—every440 Ma at the current impact rate. The age for the20 km crater would place it among the half-dozenyoungest of its size class: while possible, this is unlikely(the mapped region makes up


Fig. 4. (a) Geologic map of the study area; (b) crater count estimate of the mean age of the study area; the non-sparseness cor-rection is applied (Kneissl et al., 2016, Riedel et al., 2018).

10–7

10–6

10–5

10–4

10–3

10–2

10–1

100

100 m 1 km 10 km 100 km 1000 kmDiameter

Diff

eren

tial c

rate

r fre

quen

cy, k

m–

3

PF: Moon, Neukum (1983)CF: Moon, Neukum (1983)

0 5 Ga

Age of region, area 2.9 × 104 km2

48 craters, N(1) = 2.78 × 10–1 km–2

Ga�4.22+0.020–0.024

ShShSh

HH

50 km50 km50 kmScScSc IcIcIc

pNcpNcpNc

pNcpNcpNc

pNcpNcpNcSPASPASPA

SPASPASPA(a)(a)(a)

(b)(b)(b)

SPASPASPA

IcpIcpIcp

IcpIcpIcp

NcNcNc

NcNcNc

NcNcNc

ScScSc

ScScSc

EcEcEc

EcEcEc

Ec

Ic

Nc

pNc

SPA

Sc

Icp

Late

Early

AgeCopernican(1.1–0 Ga)

Eratosthenian(3.2–1.1 Ga)

Imbrian(3.85–3.2 Ga)

Nectarian(3.92–3.85 Ga)

Pre-Nectarian(4.6–3.85 Ga)

1.69 m/px. Figure 6 shows LROC NAC imageM137538218LC and local enlargements, showing thecharacter of the surface morphology at (1) the north-ern foot of Mons Malapert, (2) in the middle part of itsnorthern slope and (3) at its summit. The Sun eleva-tion angle was close to 4.5° when the image wasacquired, so the generally sub horizontal surfaces ofthe mountain base and summit show many shadows,while the surface of the northern slope, which isinclined by 20°–30° towards the Sun, has shadowsonly in rare fresh craters.

It is seen in Fig. 6b that the surface of the northernfoot of Malapert is covered with numerous cratersfrom a few meters to several hundred meters in diam-

eter. The area shown in this figure is close to 1 km2.The number of craters larger than 10 m in diameterhere is close to 1000 and craters larger than 100 m,about 8–10; these numbers are typical for the equilib-rium part of crater populations (Shoemaker et al.,1969; Gault, 1970) and suggest a rather ancient age forthis surface. The presence of terraced and moundedsmall craters has been interpreted to suggest the pres-ence of bedrock at depths shallower than the depth ofsampling of the crater (Quaide and Oberbeck, 1968),and thus used as a measure of regolith thickness. Allcraters, however, appear to be bowl-shaped, suggest-ing that regolith thickness here is greater than severalmeters; because of the low Sun illumination, the



Fig. 5. (a1) Vicinity of Malapert Mons enlarged central area (a2) showing locations of crater dating regions: (b) region of upperslopes of Malapert Mons, (c) ejecta of 8 km diameter impact crater, (d) ejecta of 20 km diameter impact crater, (e) inter-cratersmooth plains.

a1

e

c b

a2

d e

cb

a

20 km

1 km

10 km

5 km

5 km

(b) (c)

(d) (e)

105

104

103

102

101

100

10−1

10−2

10−3

10−4

10−51 10 100 1 10 m 100

Diameter

1 Ga

3.85 Ga

103

102

101

100

10−1

10−2

10−3

10−4

10−510 m 1 km 10 km 100 km100 m

Diameter

103104105

102

101

100

10−1

10−2

10−3

10−4

10−510 m1 m 1 km 10 km 100 km100 m

Diameter

105

104

103

102

101

100

10−1

10−2

10−3

10−4

10−51 m 10 m 100 m 1 km 10 km 100 km

Diameter

Diff

eren

tial c

rate

r fre

quen

cy, k

m3

Diff

eren

tial c

rate

r fre

quen

cy, k

m3

Diff

eren

tial c

rate

r fre

quen

cy, k

m3

Diff

eren

tial c

rate

r fre

quen

cy, k

m3





57 crators, N(1)−1.84 × 10−3 km−221 crators, N(1)−4.78 × 10−2 km−2



0

0 5 Ga

2 4 Ga0 2 4 Ga

0 2 4 Ga

μ2.2+0.3 Ga−0.3 μ2.7+0.3 Ga

−0.5

μ3.8+0.09 Ga−0.1

μ1.6+0.3 Ga−0.3

μ3.8+0.06 Ga−0.06

μ4.0+0.03 Ga−0.04

d

f loors of most prominent craters are in shadow, andthis estimate of regolith thickness awaits confirmationby additional images and analysis. Meter-sized rockboulders in association with craters in this area areonly rarely seen and thus the regolith here should bemature (Basilevsky et al., 2015).

The morphology of the summit area (Fig. 6d) israther similar to that of the mountain foot and base:we observe numerous craters from meters to hundredsmeters in diameter and a paucity of rock boulders. Theregolith thickness and maturity are likely to be similarto those at the north massif base.

The morphology of the northern slope of MalapertMons (Fig. 6c) is very different from that of the north-ern base and summit. The inclined surface (in this spe-cific case toward the NW) is characterized by numer-ous sinuous gently-sloping ridges, tens of meters longand a few meters to 10–15 wide. The ridges are gener-ally subparallel and their long axes are oriented in a


NE-SW direction, perpendicular to the localdownslope direction. Superposed on this wavy surfaceare prominent appearing small craters, meters to 10–20 m in diameter. The numbers of these craters in thisarea having diameters larger than 10 mis ~50, morethan an order of magnitude lower than the equilibriumspatial density of craters of this size on sub horizontalsurfaces (e.g., Basilevsky, 1976).

Within the part of the northern slope of Malapertcovered by the LROC NAC image M137538218LC areobserved several craters 100 to 150 m in diameter hav-ing an unusual morphology (Fig. 7).

The surface surrounding the craters shown in Fig. 7is wavy, with sinuous gentle-sloping ridges (as in otherparts of the northern slope)and from the upslope sidethis wavy surface embays inside the craters. We inter-pret this to be due to the downslope movement ofregolith material. Such crater downslope infilling andthe general wavy surface of the slope could be a result


Fig. 6. (a) Low-resolution version of LROC NAC imageM137538218LC showing positions of the enlargements(b), (c) and (d), which are full-resolution (1.05 m/px)images of the Malapert northern base, northern slope andthe summit. These enlargements cover areas 900 × 1200 meach. Lettered small squares in part (a)correspond to posi-tions of craters shown in Figs. 7 and 8.

(d)(d)(d)

(c)(c)(c)

(b)(b)(b)(a)(a)(a)aa

aa

aa

bb

bb

bb

cc

cc

cc

of the same process: downslope movement of regolithmaterial. This is certainly possible on relatively steeper(20°–30°?) slopes and could be enhanced by nearbymoonquakes (e.g., Houston et al., 1973; Asphaug andMelosh, 1993; Thomas and Robinson, 2005;Kreslavsky and and Head, 2012) whose occurrence inthe South pole region and other areas of the Moon wasrecently considered by Watters et al. (2010, 2015, 2017)and Kumar et al. (2016). After consideration of thesemodified craters on the northern slope we revisitedcraters on the Mons Malapert northern foot and sum-mit and found that some of them with rather steepinner slopes are characterized by wavy surface whilethe adjacent sub horizontal surfaces are not wavy (Fig. 8).

The suggested downslope material movementwhich could be triggered by moonquakes should beconsidered as a potential danger for elements of afuture lunar base. The moonquakes are dangerous forthe lunar base infrastructure (see e.g., Basilevsky,2017; Basilevsky et al., 2017) and any downslope mate-rial movement triggered by moon quakes increases thedanger.

TRAFFICABILITY OF THE MONSMALAPERT AREA

The normal functioning of a lunar base requiresthat various nearby and distant places are capable ofbeing visited for scientific, operational, or life-supportpurposes. As seen in Fig. 2 (and in more detail in Fig. 9),the slopes of Mons Malapert are rather steep, so theissue of traffic ability in this region deserves consider-ation.

It can be seen from Figs. 2 and 9 that the slopes ofMons Malapert are mostly rather steep: from ~20° to25° and 30°, while its summit and bases are topo-graphically more gentle. In reality the values shownshould locally be even steeper due to presence of smallcraters. To consider the issue of trafficability, wereturn to review and analyze the experience gained bythe deployment and operation on lunar the surface ofthe robotic Soviet Lunokhods 1 and 2, and the USAstronaut-operated Apollo Lunar Roving Vehicles(LRV).

Lunokhod 1 and 2Lunokhods 1 and 2 (Fig. 10) were robotic rovers

used for scientific studies in Mare Imbrium and LeM-onnier Bay of Mare Serenitatis, correspondingly. Therovers were 135 cm high and had a mass of 756 kg(Lunokhod 1) and 840 kg (Lunokhod 2). The increaseof the Lunokhod 2 mass was due to the addition of athird navigation TV camera and an increase in thenumber of scientific instruments. Lunokhods hadabout a 1.7 m wheel base and 1.6 m wheel tracks, andhad eight wheels 51 cm in diameter, each with an inde-pendent suspension, electric motor, gearbox andbrake. The width of Lunokhods is 1.96 m, and the lengthdepends on the position of the solar battery panelmounted on the lid covering the main body of the rover.With the battery lid closed, the length is approximately2.4 m, and at full deployment it reaches 2.93 m.

The rovers had two speeds, about 0.85 and 2 km/h.Lunokhod 1 was equipped with two and Lunokhod 2—with three, forward-looking navigation TV cameras,which transmitted to Earth images of the terrain alongthe route of motion and allowed the crew on Earth tocontrol the route of the mobile spacecraft. BothLunokhod 1 and 2 had four panoramic cameras, twowith horizontal scanning axes, and two with axesinclined by 15° from vertical. Figure 11 shows part ofpanoramic TV camera image taken by Lunokhod 2.




Fig. 7. Craters on the northern slope of Malapert having an unusual morphology; (a), (b), (c) parts of LROC imageM137538218LC covering areas 300 × 300 m. (d), (e), (f) The same images with the suggested interpretations.

100 m100 m100 m

(a)(a)(a) (b)(b)(b) (c)(c)(c)

(d)(d)(d) (e)(e)(e) (f)(f)(f)

Fig. 8. Selected craters with wavy surface slopes on the northern foot (a, b, c) and summit (d, e, f) of Mons Malapert. Parts ofLROC image M137538218LC covering areas 300 × 300 m.

100 m100 m100 m

(a)(a)(a) (b)(b)(b) (c)(c)(c)

(d)(d)(d) (e)(e)(e) (f)(f)(f)


Fig. 9. Topographic map of Mons Malapert based on the LOLA-based DTM LDEM80S20M_a1 with calculated values of slopesteepness shown.

150 000

140 000

130 000

120 000

110 000

100 000

–30 000 –20 000 –10 000

–1000–500

–1500–2000–2500

5000

100015002000250030003500400045005000

Altitutes, m

0 10 000 20 000 30 000 m

The width of the metal wire mesh wheel is about20 cm. The narrow lines in the lower-center part ofFig. 11 are tracks made by the free rolling 9th wheel,which was passive and was used to measure the actualdistance traversed by the rover, unaffected by wheelslippage (Fig. 12).

Apollo Lunar Roving Vehicle

The Apollo Lunar Roving Vehicle (LRV, Fig. 13),used in expeditions of Apollo 15, 16, and 17, is a four-wheeled manually-controlled, electrically-poweredrover that carried the crew and their equipment overthe lunar surface. The LRV was designed to carry thetwo astronauts and a science payload at a maximumvelocity of about 13 km/h on a smooth, level surface,and at reduced velocities on slopes up to 25 degrees. Itcan be operated from either crewman’s position, as thecontrol and display console is located on the vehiclecenterline. The deployed vehicle is 2.25 m wheel base,1.8 m wheel tracks, approximately 3.1 m long, 2.15 mwide and 1.14 m high. The four wheels of the vehicleare 81 cm in diameter and the wheel width dependedon the radial deformation of an elastic tire made in theform of a wire mesh. In the absence of a radial load onthe wheel, the width is equal to 23 cm. On lunar rego-

lith surfaces close to horizontal, the LRV tracks arevery shallow (Fig. 14). The gross operational mass isapproximately 700 kg of which 210 kg is the weight ofthe vehicle itself. The remainder is the weight of thecrew, their equipment, communications equipment,and the science payload.

The trafficability of Lunokhods and the ApolloLunar roving vehicles was studied in numerous pre-flight experiments on Earth and in driving on the lunarsurface. Figure 15 shows the results of measurementsusing engineering mockups of Lunokhod 1 and in realdriving of this rover on the lunar surface, as well as theApollo Lunar Rover Vehicle tests on terrestrial ana-logs: illustrated are the dependences of the slippage asa function of steepness of the slope of which the roverwas climbing.

It is seen in Fig. 15 that when steepness of the slopeapproached to 20°–25° the slip ratio reached 60–80%that actually meant end of normal driving. One ofauthors of this paper, the Apollo 15 astronaut DaveScott, recollects: “The LRV pulled 18 deg with no dif-ficulty. Cross-slope travel was difficult and drivinguphill easier than downhill. As I recall the angle ofrepose was about 25 deg, thus, depending on the mate-rial, about the steepest. ”Craters with climbing anglesup to 25–27 degrees also were met on the routes of the




Fig. 10. Schematic image of Lunokhod 2 (source: https//www.roscosmos.ru/24543).

Magnetometer

Omnidirectionalantena

Highly directionalantena

Solar battery

PanoramicTV cameras

NavigationTV cameras

NavigationTV camera

RIFMAXRF spectrometer

Lasercorner

detector

Fig. 11. Part of Lunokhod 2 TV panoramic image L2_D02_S02_P02_F02g.jpg showing the lunar surface inside lunar crater LeMonier with tracks made by the rover wheels in back-and-forth motions.


Fig. 12. Lunokhod mockup driving test on fresh volcanic ash near Tolbachik volcano in Kamchatka, Russia. Arrow shows the 9thwheel which was used to measure the actual path traversed.

Fig. 13. Lunar Rover Vehicle at the Apollo 15Hadley-Apennine landing site. NASA photo AS15-85-11471.

Lunokhods, but the strong slip led to real stop of thedriving.

Comparison of Figs. 9 and 15 shows that most ofthe slopes on Mons Malapert are too steep to normally

ascend them by rovers having trafficability capabilitiessimilar to that of Lunokhod 1 and 2, and would also bedifficult for the Apollo Lunar Roving Vehicle. Theoptimal possible location to drive up and down Mons



Fig. 14. Tracks of the wheels of the Lunar Roving Vehicle on the mare basalt regolith plains at the Apollo 15 landing site. Part ofphoto AS15-85-11403.

Fig. 15. Dependence of slip ratio (β) on steepness (α) ofthe slope on which the rover is climbing. (1, 2) Lunokhod1 measurements on the Moon and on Earth analogs, cor-respondingly (Malenkov, 2008). (3) The Apollo LunarRover Vehicle measurements on terrestrial analogs(Asnani et al., 2009).

2

3

80

60

40

20

3224168

1

β, %

α, deg0–8

Malapert is on its WNW rim, where slope steepness iswithin the 5°–7° range (expected slipping 5-10%) andlocally in the 10°–12° range (slipping 15–20%). Weconclude that for emergency cases and for the study ofobjects on steeper slopes or in rocky-boulder areas, itis recommended to have as standard equipment at thebase, the hybrid wheel-walking (wheel-legged) type ofrovers (Kemurjian, 1990, Leppanen, 2007; Heverly etal., 2010; Malenkov et al., 2015). A possible example ofa rover of this kind is shown in Fig. 16.

DISCUSSION AND CONCLUSIONSMalapert Mons is an attractive candidate for a

lunar base due to (1) its direct visibility from Earth,(2) its almost constant solar illumination, (3) its ‘com-fortable’ surface thermal environment, and (4) itscloseness to potential lunar water sources. Direct visi-bility from Earth is important for a reliable high-gaincommunication link between the base and missioncontrol on Earth. Almost constant solar illuminationis important to retain a powerful energy supply for thebase, and to minimize both high thermal intensitysolar illumination and to survive the extremely lowtemperatures of lunar night. ‘Comfortable’ surfacethermal environment is important for both the traverseactivity of astronauts and the design and constructionof base infrastructure. And closeness to the cratersHaworth and Shoemaker, whose f loors are in perma-nent shadow, is important as potential local sources ofwater. Recent estimations of the bearing capacity of


regolith in permanently shadowed regions of theMoon using boulder tracks, showed that it is ratherhigh; thus rovers and astronauts will be able to driveand walk in the shadowed regions(Sargeant et al.,2019; Bickel et al., 2019).


Fig. 16. Mockup of a wheel-walking rover during tests on fresh volcanic ash near Tolbachik volcano in Kamchatka, Russia.

Being part of the rim of the South-Pole-Aitkenbasin, Mons Malapert is a good place for detailedstudy and sampling of the most ancient available rocksof lunar crust, while the detailed “in-situ” study ofpermanently shadowed areas in craters Haworth andShoemaker may provide information on the natureand history of accumulation of lunar polar volatiles.

However, the ‘positive’ characteristics of this local-ity are seriously challenged by the steepness of most ofthe slopes of this mountain. As described above, the20°–30° slope steepness is very likely to seriouslyincrease the slip ratio of the rovers and the only rea-sonably good route to ascend to and descend from thesummit of Malapert is the NW crest of the mountain.Also uncertain is whether numerous up-and-downdrives along this crest will improve or worsen the traf-ficability of this route.

So the general conclusion of our work is: MonsMalapert is a potentially attractive locality for thelunar base, but difficulties in trafficability of most ofits slopes is a serious challenge for this choice. Addi-tional studies of both advantages and disadvantages ofthis locality are necessary. In particular, it is necessaryto take into account that the base infrastructure mustinclude a f leet of robotic and human all-terrain vehi-cles. Not only the effectiveness of scientific researchon difficult terrain, but also the safety of people inemergency situations depends on their driving charac-teristics and their reliability.

FUNDING

This work was partly supported by Russian ScienceFoundation, project no. 17-17-01149, and Institute furGeologische Wissenschaften, Freie Universitaet Berlin. Wegratefully acknowledge financial support from the NASASolar System Exploration Research Virtual Institute(SSERVI) grant for Evolution and Environment of Explo-ration Destinations under cooperative agreement numberNNA14AB01A at Brown University.

REFERENCESAllender, E.J., Orgel, C., Almeida, N.V., Cook, J., Ende, J.J.,

Kamps, O., Mazrouei, S., Slezak, T.J., Soini, A.-J.,and Kring, D.A., Traverses for the ISECG-GER designreference mission for humans on the lunar surface, Adv.Space Res., 2019, vol. 63, pp. 692–727. https://doi.org/10.1016/j.asr.2018.08.032

Asnani, V., Delap, D. and Creager, C. The Development ofWheels for the Lunar Roving Vehicle: NASA/TM–2009-215798, Hanover, MD: NASA Center Aerospace Inf.,2009.

Asphaug, E. and Melosh, H.J., The Stickney impact ofPhobos: a dynamical model, Icarus, 1993, vol. 101,pp. 144–164. https://doi.org/10.1006/icar.1993.1012

Basilevsky, A.T., On the evolution rate of small lunar cra-ters, Proc. 7th Lunar and Planetary Science Conf.,Houston, TXL Lunar Planet. Inst., 1976, pp. 1005–1020.

Basilevsky, A.T., Lunar base, polar water and danger of themoonquakes, Priroda (Moscow), 2017, no. 11, pp. 67–72.



Basilevsky, A.T., Head, J.W., Horz, F., and Ramsley, K.,Survival times of meter-sized rock boulders on the sur-face of airless bodies, Planet. Space Sci., 2015, vol. 117,pp. 312–328. https://doi.org/10.1016/j.pss.2015.07.003

Basilevsky, A.T., Ivanov, M.A., Krasilnikov, S.S., Zakharo-va, M.A., Head, J.W., and Deutsch, A. Recent tectonicdeformation in the South Pole area of the Moon, Proc.8th Moscow Solar System Symp., Moscow, 2017, no.8MS3-PG-02.

Bickel, V.T., Honniball, C.I., Martinez, S.N., Rogaski, A.,Sargeant, H.M., Bell, S.K., et al., Analysis of LunarBoulder Tracks: implications for trafficability of pyro-clastic deposits, J. Geophys. Res.: Planets, 2019, vol. 124. https://doi.org/10.1029/2018JE005876

Burke, J.D., Merits of lunar polar base location, in LunarBases and Space Activities of the 21st Century, Mendel, W.W.,Ed., Houston, TX: Lunar Planet. Inst., 1985, pp. 77–84.

Colaprete, A., Schultz, P., Heldmann, J. et al., Detection ofwater in the LCROSS ejecta plume, Science, 2010,vol. 330, pp. 463–468.

Cooper, B.L. and Simon, T., SAE Technical Report 2007-01-3106ISRU: Production of Life Support Consumablesfor a Lunar Base, Warrendale, PA: SAE Int., 2007. https://doi.org/10.4271/2007-01-3106

Feldman, W.C., Maurice, S., Binder, A.B., Barraclough, B.L.,Elphic, R.C., and Lawrence, D.J., Fluxes of fast andepithermal neutrons from Lunar Prospector: evidencefor water ice at the lunar poles, Science, 1998, vol. 281,no. 5382, pp. 1496–1500.

Garrick-Bethell, I. and Zuber, M.T., Elliptical structure ofthe lunar South Pole-Aitken basin, Icarus, 2009,vol. 204, pp. 399–408.

Gault, D.E., Saturation and equilibrium conditions for im-pact cratering on the lunar surface: criteria and implica-tions, Radio Sci., 1970, vol. 5, pp. 273–291.

Heverly, M., Matthews, J., Frost, M. and McQuin, C., De-velopment of the Tri-ATHLETE Lunar vehicle proto-type, Proc. 40th Aerospace Mechanisms Symp., NASAKennedy Space Center, May 12–14, 2010, Washington,DC: Natl. Aeronaut. Space Admin., 2010, no. NA-SA/CP-2010-216272, pp. 317–326.

Hiesinger, H., Head, J.W., Wolf, U., Jaumann, R., andNeukum, G., Lunar mare basalt f low units: Thickness-es determined from crater size-frequency distributions,Geophys. Res. Lett., 2002, vol. 29, no. 8. https://doi.org/10.1029/2002GL014847

Houston, W.N., Moriwaki, Y., and Chang, C.-S.,Downslope movement of lunar soil and rock caused bymeteoroid impact, Geochim. Cosmochim. Acta, 1973,vol. 3, suppl. 4, pp. 2425–2435.

Ivanov, M.A., Hiesinger, H., van der Bogert, C.H., Orgel, C.,Pasckert, J.H., and Head, J.W., Geologic history of thenorthern portion of the South Pole–Aitken basin onthe Moon, J. Geophys. Res.: Planets, 2018, vol. 123, https://doi.org/10.1029/2018JE005590

Kemurjian, A., From the Moon rover to the Mars rover,Planet. Rep., 1990, vol. 10, no. 4, pp. 4–11.

Kneissl, T., Michael, G.G., and Schmedemann, N., Treat-ment of non-sparse cratering in planetary surface dat-ing, Icarus, 2016, vol. 277, pp. 187–195.


Kreslavsky, M.A. and Head, J.W., New observational evi-dence of global seismic effects of basin-forming im-pacts on the Moon from Lunar Reconnaissance OrbiterLunar Orbiter Laser Altimeter data, J. Geophys. Res.:Planets, 2012, vol. 117, p. E00H24. https://doi.org/10.1029/2011JE003975

Kumar, P.S., Sruthi, U., Krishna, N., Lakshmi, K.J., Me-non, P., Amitabh, R., Krishna, B.G., Kring, D.A.,Head, J.W., Goswami, J.N., and Kumar, A.S.K., Re-cent shallow moonquake and impact-triggered boulderfalls on the Moon: new insights from Schrödinger basin, J.Geophys. Res.: Planets, 2016, vol. 121, pp. 147–179. https://doi.org/10.1002/2015JE004850

Lawrence, D.J., Feldman, W.C., Elphic, R.C., Little, R.C.,Prettyman, T.H., Maurice, S., Lucey, P.G., and Bind-er, A.B., Iron abundances on the lunar surface as mea-sured by the Lunar Prospector gamma-ray and neutronspectrometers, J. Geophys. Res.: Planets, 2002, vol. 107,p. 5130, https://doi.org/10.1029/2001JE001530

Lawrence, D.J., Elphic, R.C., Feldman, W.C., Pretty-man, T.H., Gasnault, O., and Maurice, S., Small-areathorium features on the lunar surface, J. Geophys. Res.:Planets, 2003, vol. 108, p. 5102. https://doi.org/10.1029/2003JE002050

Leppanen, I., Automatic Locomotion Mode Control ofWheel-Legged Robots, Research Reports no. 30, Hel-sinki: Helsinki Univ. Technol., 2007.

Malenkov, M.I., Ekstremal’naya robototekhnika. Proektiro-vanie sistem peredvizheniya planetokhodov (Extreme Ro-botics: Design of Driving Systems of Planetary Rovers),St. Petersburg: S.-Peterb. Gos. Politekh. Univ., 2008.

Malenkov, M.I., Volov, V.A., Guseva, N.K., and Lazarev, E.A.,Increasing the mobility of Mars rovers by improving thelocomotion systems and their control algorithms, Russ.Eng. Res., 2015, vol. 35, no. 11, pp. 824–831.

Neukum, G., Meteorite bombardment and dating of plan-etary surfaces, 1983. http://ntrs.nasa.gov/search.jsp?R=19840027189.

Paige, D.A., Siegler, M.A., Zhang, J.A., et al., Diviner Lu-nar radiometer observations of cold traps in the Moon’ssouth polar region, Science, 2010, vol. 330, pp. 479–482.

Quide, W.L. and Oberbeck, W.R. Thickness determinationof the lunar surface layer from lunar impact craters, J.Geophys. Res., 1968, vol. 73, pp. 5247–5270.

Riedel, C., Michael, G., Kneissl, T., Orgel, C., Hiesinger, H.,and Bogert van der, C.H., A new tool to account forcrater obliteration effects in crater size-frequency dis-tribution measurements, Earth Space Sci., 2018, vol. 5,pp. 258–267.

Sanin, A.B., Mitrofanov, I.G., Litvak, M.L., et al., Hydro-gen distribution in the lunar polar regions, Icarus, 2017,vol. 283, pp. 20–30.

Sargeant, H.M., Bickel, V.T., Honniball, C.I., Martinez, S.N.,Rogaski, A., Bell, S.K., Czaplinski, E.C., Farrant, B.E.,Harrington, E.M., Tolometti, G.D., and Kring, D.A.,Determining the bearing capacity of permanently shad-owed regions of the Moon using boulder tracks, Proc.50th Lunar and Planetary Science Conf., Houston, TX:Lunar Planet. Inst., 2019, no. 1792.


Sharpe, B.L. and Schrunk, D.G., Malapert Mountain:gateway to the Moon, Adv. Space Res., 2003, vol. 31,no. 11, pp. 2467–2472. https://doi.org/10.1016/SO273-1177(03)00535-O

Shoemaker, E.M., Batson, R.M., Holt, H.E., Morris, E.C.,Rennilson, J.J., and Whitaker, E.A., Observations oflunar regolith and the Earth from the television cameraon Surveyor 7, J. Geophys. Res., 1969, vol. 74,pp. 6081–6119.

Thomas, P.C. and Robinson, M.S., Seismic resurfacing bya single impact on the asteroid 433 Eros, Nature, 2005,vol. 436, pp. 366–369. https://doi.org/10.1038/nature03855

Tye, A.R., Fassett, C.I., Head, III, J.W., Mazarico, E., Ba-silevsky, A.T., Neumann, G.A., Smith, D.E., and Zu-ber, M.T., The age of lunar south circumpolar cratersHaworth, Shoemaker, Faustini, and Shackleton: impli-cations for regional geology, surface processes, and vol-atile sequestration, Icarus, 2015, vol. 255, pp. 70–77. https://doi.org/10.1016/j.icarus.2015.03.016

Watters, T.R., Robinson, M.S., Beyer, R.A., et al., Evi-dence of recent thrust faulting on the Moon revealed bythe Lunar Reconnaissance Orbiter Camera, Science,2010, vol. 329, pp. 936–940.

Watters, T.R., Robinson, M.S., Collins, G.C., et al., Globalthrust faulting on the Moon and the influence of tidalstresses, Geology, 2015, vol. 43, no. 10, pp. 851–854.

Watters, T.R., Weber, R.C., Collins, G.C., and Johnson, C.L.,Shallow lunar seismic activity and the current stressstate of the Moon, Proc. XLVIII Lunar and PlanetaryScience Conf., Houston, TX: Lunar Planet. Inst., 2017,no. 2569.

Wilhelms, D., Geologic History of the Moon: USGS SpecialPaper 1348, Washington, DC: US Gov. Publ. Off.,1987.

Wilhelms, D.E., Howard, K.A., and Wilshire, H.G., Geo-logic Map of the South Side of the Moon, US GeologicalSurvey Map I-1192, Washington, DC: US Gov. Publ.Off., 1979.

Zelenyi, L., Milestones of the Russian space science pro-gram for the decade 2016–2025, Proc. Seventh MoscowSolar System Symposium 7M-S3, Moscow, Russia, Octo-ber 10–14, 2016, Moscow: Space Res. Inst., 2016, no.7MS3_OS_01.

Zuber, M.T., Smith, D.E., Lemoine, F.G., and Neu-mann, G.A., The shape and internal structure of theMoon from the Clementine mission, Science, 1994,vol. 266, pp. 1839–1843.


INTRODUCTIONTOPOGRAPHY AND ITS DERIVATIVESGENERAL GEOLOGY OF THE MONS MALAPERT AREASURFACE MORPHOLOGYTRAFFICABILITY OF THE MONS MALAPERT AREALunokhod 1 and 2Apollo Lunar Roving Vehicle

DISCUSSION AND CONCLUSIONSREFERENCES

Documents

Potential Lunar Base on Mons Malapert: Topographic ...tain Mons Malapert (MM) near the South pole of the Moon is a key candidate for the location of such a base. MM is an ~30 × 50