Modeling of different initial spatial profile and velocity distribution shows how physical processes affect exospheric distribution. We have detailed that the inventory from infalling micrometeoroids is not the prime contributor to H2 in the lunar exosphere. The solar wind is a sufficient source of hydrogen that can supply the observed H2 exosphere by chemical sputtering of implant solar wind H. To produce H2 density of 1200 cm−3, 10% of the solar wind would need to be converted to H2.