Neutral sodium atoms release from the surfaces of the Moon and Mercury induced by meteoroid impacts

In this work, we calculate the neutral Na production rates on the Moon and Mercury, as due to the impacts of meteoroids having an impact probability on the surface that can influence the daily observations of the exosphere: the meteoroids radius range considered for the Moon and Mercury are 10(-8)-0.15 and 10(-8)-0.10 m, respectively. We also estimate the mass of meteoroids that has impacted the surfaces of the Moon and Mercury in the last 3.8 Gy (after the end of the Late Heavy Bombardment). The results of our model are that (i) the Na production rates are similar to(3-4.9) x 10(4) and similar to(1.8-2.3) x 10(6) atoms cm(-2) s(-1), for Moon and Mercury, respectively, and (ii) in the last 3.8 Gy, the mass of meteoroids that has impacted the whole surface of the Moon and Mercury has been 8.86 x 10(18) and 2.66 x 10(19) g, respectively. (C) 2007 Elsevier Ltd. All rights reserved.