Potter A E, Morgan T H
Science. 1988 Aug 5;241(4866):675-80. doi: 10.1126/science.241.4866.675.
Spectra of the region just above the bright limb of the Moon show weak emission features that are attributed to resonant scattering of sunlight from sodium and potassium vapor in the lunar atmosphere. The maximum omnidirectional emission flux above the bright limb is 3.8 +/- 0.4 kilorayleighs for sodium and 1.8 +/- 0.4 kiloray-leighs for potassium. The zenith column densities above the subsolar point are estimated to be 8 +/- 3 x 10(8) atoms cm(-2) for sodium 1.4 +/- 0.3 x 10(8) atoms cm(-2) for potassium. Corresponding surface densities are 67 +/- 12 atoms cm(-3) and 15 +/- 3 atoms cm(-3), respectively. The scale height for the sodium atmosphere is 120 +/- 42 kilometers, and for potassium 90 +/- 20 kilometers, which implies that the effective temperature of the sodium and potassium is close to the lunar surface temperature. The sodium density at the south polar region was found to be similar to that at the subsolar point, indicating wide-spread distribution of sodium vapor over the lunar surface. The ratio of the density of sodium to the density of potassium is (6 +/- 3) to 1, which is close to the sodium to potassium ratio in the lunar surface, suggesting that the atmosphere originates from the vaporization of surface minerals.
月球亮边缘上方区域的光谱显示出微弱的发射特征，这些特征归因于太阳光被月球大气中的钠和钾蒸汽共振散射。亮边缘上方的最大全向发射通量，钠为3.8±0.4千勒，钾为1.8±0.4千勒。日下点上方的天顶柱密度估计，钠为8±3×10⁸原子/厘米²，钾为1.4±0.3×10⁸原子/厘米²。相应的表面密度分别为67±12原子/厘米³和15±3原子/厘米³。钠大气的标高为120±42千米，钾大气的标高为90±20千米，这意味着钠和钾的有效温度接近月球表面温度。发现南极地区的钠密度与日下点处的相似，表明钠蒸汽在月球表面广泛分布。钠与钾的密度比为（6±3）比1，这与月球表面的钠钾比接近，表明大气起源于表面矿物的汽化。
