WAC Hapke Photometric Parameter Maps
Spatially resolved near-global Hapke photometric parameter maps of the Moon from about 66,000 LROC Wide Angle Camera (WAC) multispectral observations acquired from February 2010 to October 2011. Maps consist of 9 Hapke parameters (w, b, c, Bc0, hc, Bs0, hs, θ, φ) [1] for each of the 7 bands of the WAC in Equirectangular projection (centered at 0°N, 0°E; 1° by 1° pixel scale). The parameters Bc0, hc, θ, and φ (band 4, 5, 8, and 9) are constant values as described in [1]. Maps extend 0°E-360°E, 70°N-70°S. These maps were used to normalize the observed reflectance at standard angles incidence=phase=60°, emission=0° in 1° latitude by 1° longitude tiles. For more information on the derivation of the Hapke parameters, please refer to Sato, et al. (2014).
Free Parameters of the Hapke Model [1]:
Symbols |
Name |
w |
Single scattering albedo |
b |
Henyey-Greenstein double-lobed single particle phase function parameter |
c |
Henyey-Greenstein double-lobed single particle phase function parameter |
Bc0 |
Amplitude of Coherent Backscatter Opposition Effect (CBOE) - fixed at 0.0 |
hc |
Angular width of CBOE - fixed at 1.0 |
Bs0 |
Amplitude of Shadow Hiding Opposition Effect (SHOE) |
hs |
Angular width of SHOE |
θ |
Effective value of the photometric roughness - fixed at 23.657 |
φ |
Filling factor - fixed at 1.0 |
PDS Product Naming Convention: The Hapke photometric parameter maps are archived as 9-band products for each of the 7 WAC bands as well as one 63-band product containing all 9 parameters for all 7 bands of the WAC. The 9 Hapke parameters are archived in the order presented in the table above to create each 9-band product (i.e. Band 1 is for the w parameter and Band 9 has the φ parameter). For the 63-band product, the WAC bands are in order of increasing wavelength (i.e. Band 1 contains the w parameter for 321 nm WAC band and Band 63 contains the phi parameter for the 689 nm WAC band). All the product files are named in the following manner: WAC_HAPKEPARAMMAP_[wavelength, e.g., 321NM or 7BAND]
Product Name |
WAC Band |
# of Bands |
WAC_HAPKEPARAMMAP_321NM |
321 nm (WAC band 1) |
9 |
WAC_HAPKEPARAMMAP_360NM |
360 nm (WAC band 2) |
9 |
WAC_HAPKEPARAMMAP_415NM |
415 nm (WAC band 3) |
9 |
WAC_HAPKEPARAMMAP_566NM |
566 nm (WAC band 4) |
9 |
WAC_HAPKEPARAMMAP_604NM |
604 nm (WAC band 5) |
9 |
WAC_HAPKEPARAMMAP_643NM |
643 nm (WAC band 6) |
9 |
WAC_HAPKEPARAMMAP_689NM |
689 nm (WAC band 7) |
9 |
WAC_HAPKEPARAMMAP_7BAND |
All 7 wavelengths |
63 |
Product Citation:
Sato, H., Robinson, M.S., Hapke, B., Denevi, B.W., Boyd, A.K. (2014) Resolved Hapke parameter maps of the Moon. Journal of Geophysical Research Planets, 119, 1775–1805. doi:10.1002/2013JE004580.
RDR SIS:
http://lroc.sese.asu.edu/data/LRO-L-LROC-5-RDR-V1.0/LROLRC_2001/DOCUMENT/RDRSIS.PDF
References:
[1] Hapke, B. (2012) Theory of reflectance and emittance spectroscopy. Cambridge University Press, New York.