The intrinsic magnetic field of the Moon

Abstract

We report here preliminary observations of the magnetic field in the near neighborhood of the moon taken during the first and second lunar orbits of Explorer 35. The spacecraft was launched from Eastern Test Range at 1419 UT on July 19 (digital day 199), and lunar injection took place at 0920 UT on July 22 (day 202). The first two perilune passes were executed while the satellite was immersed within the geomagnetic tail structure. The orbital parameters of interest are semimajor axis 3.43 RM, semiminor axis 2.80 RM) where RM = 1.74 × 103 km, period 11.5 hours, and eccentricity 0.580.