  (21) Lutetia has been visited by Rosetta mission on July 2010 and observed
with a phase angle ranging from 0.15 to 156.8 degrees. The Baetica region,
located at the north pole has been extensively observed by OSIRIS cameras
system. Baetica encompass a region called North Pole Crater Cluster (NPCC),
shows a cluster of superposed craters which presents signs of variegation at
the small phase angle images. For studying the location, we used 187 images
distributed throughout 14 filter recorded by the NAC (Narrow Angle Camera) and
WAC (Wide Angle Camera) taken during the fly-by. We photometrically modeled the
region using Minnaert disk-function and Akimov phase function to finally
reconstruct a resolved spectral slope map at 5 and 20 degrees of phase angle.
We observed a dichotomy between Gallicum and Danuvius-Sarnus Labes in the NPCC,
but no significant phase reddening. In the next step, we applied the Hapke
(2008, 2012) model for the NAC F82+F22 (649.2 nm), WAC F13 (375 nm) and WAC F17
(631.6 nm), enabling us to compose the normal albedo and Hapke parameter maps
for NAC F82+F22. On Baetica, the 649 nm global properties are: geometric albedo
of 0.205+-0.005, the average single-scattering albedo of 0.181+-0.005, the
average asymmetric factor of -0.342+-0.003, the average shadow-hiding
opposition effect amplitude and width respectivelly of 0.824+-0.002 and
0.040+-0.0007, the average roughness slope of 11.45+-3 deg. and the average
porosity is 85+-0.2%. In the NPCC, the normal albedo variegation among the
craters walls reach 8% brighter for Gallicum Labes and 2% fainter for Danuvius
Labes. The Hapke parameter maps also show a dichotomy at the opposition effect
coefficients, single-scattering albedo and asymmetric factor, that may be
attributed to the maturation degree of the regolith or to compositonal
variation.
