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MGM2011 3 arcmin-resolution Mars 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 2015-03-26

1. SUMMARY
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MGM2011 is a Mars gravity field model that resolves features down to 
spatial scales of 3 km. The model is constructed as a composite of 
Newtonian forward-modelling and a recent MRO110B2 gravity field model 
MGM2011 surface gravity accelerations and free-air anomalies, 
areoid undulations and vertical deflections are provided at 0.05 degree 
resolution (3600 x 7200 = 25.92 million points) over the entire Martian 
surface. MGM2012 was released in 2012.

Citation:
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Hirt, C., S.J. Claessens, M. Kuhn and W.E. Featherstone (2012),
Kilometer-resolution gravity field of Mars: MGM2011, Planetary and Space
Science 67(2012), 147-154, doi: 10.1016/j.pss.2012.02.006

Permanent link to the MGM2011 data sets 
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http://ddfe.curtin.edu.au/models/MGM2011/            


2. INPUT DATA AND PROCESSING
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is described at geodesy.curtin.edu.au/research/models/MGM2011/
and at http://ddfe.curtin.edu.au/models/MGM2011/MGM2011_website.pdf
and at http://ddfe.curtin.edu.au/models/MGM2011/hirt2012_MGM2011.pdf


3. MGM2011 ARCHIVED PRODUCTS
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are organized in following directories

/data      .. contains 13 3-km resolution grids of MGM2011 \
              functionals and input data sets  
                               
/images    .. contains high-resolution images from the MGM2011 websites

/software  .. contains a Matlab script to read the MGM2011 binary grids

/pdf_journal_papers .. contains MGM2011-related papers


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 et al. (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 intended or unintended 
purpose.