diff --git a/Utilities/otbossimplugins/ossim/otb/PlatformPosition.cpp b/Utilities/otbossimplugins/ossim/otb/PlatformPosition.cpp
index 9117dbd4df166820d9d7377083a055c83a23aa77..ced5eac3861d286551cba119b6632d09224e4363 100644
--- a/Utilities/otbossimplugins/ossim/otb/PlatformPosition.cpp
+++ b/Utilities/otbossimplugins/ossim/otb/PlatformPosition.cpp
@@ -82,7 +82,7 @@ PlatformPosition::PlatformPosition(Ephemeris** data, int nbrData):
    }
 }
 
-Ephemeris* PlatformPosition::Interpolate(JSDDateTime date)
+Ephemeris* PlatformPosition::Interpolate(JSDDateTime date) const
 {
    const double JOURCIVIL_LENGTH = 86400.0 ;
    Ephemeris* ephem = NULL;
diff --git a/Utilities/otbossimplugins/ossim/otb/PlatformPosition.h b/Utilities/otbossimplugins/ossim/otb/PlatformPosition.h
index d907e79841669552f031d3e152c67c4bdd4053f0..86555ebabf7049eb106592bd193d04655ace65b9 100644
--- a/Utilities/otbossimplugins/ossim/otb/PlatformPosition.h
+++ b/Utilities/otbossimplugins/ossim/otb/PlatformPosition.h
@@ -64,9 +64,9 @@ public:
     * @param date Date and time at wich the interpolation have to be done
     * @return The ephemeris at the given date, or NULL if an error occurs
     */
-   Ephemeris* Interpolate(JSDDateTime date);
+   Ephemeris* Interpolate(JSDDateTime date) const;
 
-   PlatformPosition* Clone()
+   PlatformPosition* Clone() const
    {
       return new PlatformPosition(*this);
    };