<P> Elements known to be present on the lunar surface include, among others, oxygen (O), silicon (Si), iron (Fe), magnesium (Mg), calcium (Ca), aluminium (Al), manganese (Mn) and titanium (Ti). Among the more abundant are oxygen, iron and silicon . The oxygen content is estimated at 45% (by weight). Carbon (C) and nitrogen (N) appear to be present only in trace quantities from deposition by solar wind . </P> <P> Neutron spectrometry data from Lunar Prospector indicate the presence of hydrogen (H) concentrated at the poles . </P> <P> For a long period of time, the fundamental question regarding the history of the Moon was of its origin . Early hypotheses included fission from Earth, capture, and co-accretion . Today, the giant impact hypothesis is widely accepted by the scientific community . </P> <P> The geological history of the Moon has been defined into six major epochs, called the lunar geologic timescale . Starting about 4.5 billion years ago, the newly formed Moon was in a molten state and was orbiting much closer to Earth resulting in tidal forces . These tidal forces deformed the molten body into an ellipsoid, with the major axis pointed towards Earth . </P>

What is the surface are of the moon