  We investigate the possibility that the Moon develops an electric potential
originating from the impinging particles on the Moon from cosmic rays and solar
wind. The investigation includes all experimental data of the flux of charged
particle for energies higher than 865 eV available from Apollo missions,
satellites and balloon experiments in publications or from the Internet in
2008. A fictive electric potential of the Moon was calculated if the Moon
material is an isolator for the Moon solar side and lee side,if the Moon
material is a conductor for the whole Moon surface, and if the Moon is located
in the geomagnetic tail of the Earth. The calculation for these four cases
results in positive electric potentials of the Moon of 1789 V, 261 MV, 1789 V,
and 96 MV. This is originated from the unequal distribution of positive and
negative charges in the plasma of the cosmic rays and solar wind impinging on
the Moon. As the cosmic rays arrive from deep space, these findings would imply
a charge imbalance in the cosmos. This is in distinct conflict with a charge
neutral universe. We suggest searching for a so far not measured low energy
negative flux of charged particles in the cosmos or an interaction between
charged objects in the universe with the vacuum.
