The Advanced Spaceborne Thermal Emission and Reflection and Radiometer (ASTER), Multi-angle Imaging Spectroradiometer (MISR) and Moderate Resolution Imaging Spectroradiometer (MODIS) are all onboard the Terra platform. An important aspect of the use of MODIS, and other Earth Science Enterprise sensors, has been the characterization and calibration of the sensors and validation of their data products. The Remote Sensing Group at the University of Arizona has been active in this area through the use of ground-based test sites. This paper presents the results from the reflectance-base approach using the Railroad Valley Playa test site in Nevada for ASTER, MISR, and MODIS and thus effectively a cross-calibration between all three sensors. The key to the approach is the measurement of surface reflectance over a 1-km2 area of the playa and results from this method shows agreement with MODIS to better than 5%. The paper examines biases between ASTER and the other two sensors in the VNIR due to uncertainties in the onboard calibrator for ASTER and in the SWIR due to an optical crosstalk effect.