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LGM2011 3 arcmin-resolution Lunar Gravity Model  - readme-file V1.0
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Contact: Christian Hirt 
Western Australian Centre for Geodesy
Curtin University Perth
c.hirt(use the at here)curtin.edu.au &
c.hirt(use the at here)tum.de

Last edited 2015-03-24

1. SUMMARY
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LGM2011 is a lunar gravity field model that resolves features down to 
spatial scales of 1.5 km. The model is constructed as a composite of 
Newtonian forward-modelling and a recent SELENE gravity field model 
(SGM100i). LGM2011 surface gravity accelerations and free-air anomalies, 
selenoid undulations and vertical deflections are provided at 0.05 degree 
resolution (3600 x 7200 = 25.92 million points) over the entire lunar 
surface. LGM2012 was released in 2012.

Citation:
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Hirt, C. and W.E. Featherstone (2012), A 1.5 km resolution gravity field 
model for the Moon, Earth and Planetary Science Letters (EPSL) 329-330, 
22-30, doi: 10.1016/j.epsl.2012.02.012.


Permanent link to the LGM2011 data sets 
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http://ddfe.curtin.edu.au/models/LGM2011/            


2. INPUT DATA AND PROCESSING
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is described at geodesy.curtin.edu.au/research/models/LGM2011/
and at http://ddfe.curtin.edu.au/models/LGM2011/LGM2011_website.pdf
and at http://ddfe.curtin.edu.au/models/LGM2011/hirt_featherstone2012_LGM2011.pdf


3. LGM2011 ARCHIVED PRODUCTS
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are organized in following directories

/data      .. contains 13 1.5 km resolution grids of LGM2011 \
              functionals and input data sets  
                               
/images    .. contains high-resolution images from the LGM2011 websites

/software  .. contains a Matlab script to read the LGM2011 binary grids

4. FORMAT DESCRIPTION
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Each file (50,625 KB) contains 7,200 x 3,600 =25,920,000 values stored 
in 2-byte integer big-endian format (int16, ieee-be). The grid resolution 
is 0.05 deg (3 arc min). Records proceed along meridians from South to 
North and columns proceed from West to East. The first record is the 
South-West corner (-89.975 deg latitude, -179.975 deg longitude), the second 
record is (-89.92 5deg latitude, -179.975 deg longitude) and the last record 
is the North-East corner (89.975 deg latitude, 179.975 deg longitude). 
  
REFERENCES
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are given in Hirt, C. and W.E. Featherstone (2012).

DISCLAIMER
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Neither Curtin University nor any of its staff accept any liability in 
connection with the use of data and models provided here. Neither Curtin 
University nor any of its staff make any warranty of fitness, completeness, 
usefulness and accuracy of the data and models for any intented or unintended 
purpose.