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Availability: Archived at NSSDC, accessible from elsewhere


This description was generated automatically using input from the Planetary Data System.

Data Set Overview ================= This data set contains processed LP-GRS time-series data that are used as the fundamental data for deriving composition measurements of the lunar surface using either energy window techniques or the full modeling of the neutron and gamma ray transport processes. These data have been processed to eliminate bad data as well as to make corrections due to time variations in the cosmic ray flux, LP-GRS gain, LP-GRS orientation, and altitude above the lunar surface. For details of the processing applied to this data set, the reader is referred to the paper 'Gamma-ray Measurements from Lunar Prospector: Time-Series Data Reduction for the Gamma-Ray Spectrometer', Lawrence et al. (2004), J. Geophys. Res., 109, E07S05, doi:10.1029/2003JE002206 [LAWRENCEETAL2004].

Data Set Overview ================= From January 1998 to July 1999, Lunar Prospector continuously measured the leakage flux of neutrons from the Moon in four distinct energy ranges from 0 eV to 8 MeV, using two 3He tubes within the Neutron Spectrometer (NS) and the anti-coincidence shield of the Gamma-Ray Spectrometer (GRS). The neutron data have been reduced to four maps, which can be interpreted in terms of elemental composition of the lunar regolith. The main characteristics of each map are, for thermal neutrons: energy range 0 - 0.3 eV, dynamic range 95%, precision 2.7%, resolution 46 km, in units of counts/8-sec; for epithermal neutrons: energy range >0.3 eV, dynamic range 15%, precision 1%, resolution 43 km, in units of counts/8-sec; for moderated neutrons: energy range 0 - 0.8 MeV, dynamic range 15%, precision 1.8%, resolution < 90 km, in units of counts/32-sec; for fast neutrons: energy range 0.8 - 8 MeV, dynamic range 30%, precision 1.6%, resolution 46 km, in units of counts/32-sec. All maps are normalized to 30 km altitude, to the equator; and to the flux of comic rays in January 1998. They are presented as 720x360 arrays equally-spaced in latitude and longitude. Results are reproducible from raw data that are available at the Planetary Data System (PDS), together with guidance and numerical values in the paper Reduction of Neutron Data from Lunar Prospector, Maurice et al., J. Geophys. Res. 109, E07S04, doi:10.1029/2003JE002208, 2004 [MAURICEETAL2004]. The reader is referred to this publication for complete details of the processing applied to this data set.

These data are available on-line from the Planetary Data System (PDS) at:

Alternate Names

  • LP-L-GRS-3-RDR-V1.0
  • LP-L-NS-3-RDR-V1.0


  • Planetary Science: Geology and Geophysics

Additional Information



Questions and comments about this data collection can be directed to: Dr. David R. Williams



NameRoleOriginal AffiliationE-mail
Dr. William C. FeldmanData ProviderLos Alamos National
Mr. David M. LawrenceGeneral ContactUniversity of
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