Fig. 1. Topography around Mons Rümker region, which is figured out with a white box. The black box indicates the candidate landing site of CE-5 proposed by reference [10], and this site is centered at (303.34ºE, 40.11ºN)

Fig. 2. Schematic of illumination condition

Fig. 3. Morning map of illumination over Mons Rümker at the lunar local time t_m = 06:30:30: (a) Japan’s SELENE morning map of illumination; (b) our estimated relative intensity of illumination at the same time of Fig. 3(a)

Fig. 4. Surface temperature distribution with time over Mons Rümker plateau: (a) Time at UTC 2020-10-28T 11:30:00; (b) time at UTC 2020-10-29T 06:45:00; (c) time at UTC 2020-10-30T 06:45:00; (d) time at UTC 2020-11-02T 04:45:00; (e) time at UTC 2020-11-12T 02:45:00; (f) time at UTC 2020-11-12T 17:00:00

Fig. 5. Subsurface temperature distribution at the depth of 5 cm over Mons Rümker plateau: (a) Time at UTC 2020-10-28T 11:30:00; (b) time at UTC 2020-10-29T 06:45:00; (c) time at UTC 2020-10-30T 06:45:00; (d) time at UTC 2020-11-02T 04:45:00; (e) time at UTC 2020-11-12T 02:45:00; (f) time at UTC 2020-11-12T 17:00:00

Fig. 6. Temperature variation along the longitude direction shown in Fig.1: (a) Time at UTC 2020-10-28T 11:30:00; (b) time at UTC 2020-10-29T 06:45:00; (c) time at UTC 2020-10-30T 06:45:00; (d) time at UTC 2020-11-02T 04:45:00; (e) time at UTC 2020-11-12T 02:45:00; (f) time at UTC 2020-11-12T 17:00:00. The black carves in Fig. 6(d) represents the surface topography along the same blue line direction displayed in Fig. 1

Fig. 7. Subsurface temperature variations: (a) Variations for the point of CE-5 candidate landing site; (b) variations for the black star in Fig. 1

Fig. 8. Subsurface temperature variations with depth for the point of black star in Fig. 1: (a) Temperature variations at the lunar local time t_m = 06:30:30; (b) temperature variations at the lunar local time t_m = 12:30:30; (c) temperature variations at the lunar local time t_m = 18:30:30

Table 1. Values of parameters used in study

Table 2. Temperature (in K) variations with depth for the point of black star in Fig. 1 at various lunar local time