Fig. 1

Temperature dependence of the permittivity. a Anorthosite, b Basalt, c Dunite, and d Ilmenite. The circular points are the average of 10 points below and above each frequency (e.g., the average of the permittivity from 1.984–2.018  GHz in the case of 2 GHz). In the case of 6 GHz, it is averaged with the 10 points only below the frequency (i.e., the average of the permittivity from 5.966 to 6.000 GHz). The error bar shows the standard error. The colour shows the frequency (dark purple: 2 GHz, light blue: 3 GHz, green: 4 GHz, orange: 5 GHz, and dark red: 6 GHz), while the horizontal line shows the calculation result based on Eq. 1. in magenta, where appropriate. The calculation result is only shown in the case of the anorthosite and basalt, because Eq. 1 was derived from the Apollo sample and the dunite and ilmenite are minor components in the Apollo sample