Prof. Yunzhao Wu
Purple Mountain Observatory, Chinese Academy of Sciences, China
Title: Compositions of asteroids and satellite calibration using the Moon
Abstract:
Understanding the components of asteroids plays an important role in guiding research on the origin and evolution of asteroids, utilization of space resources, and asteroid defense. The mineral composition and the taxonomy of asteroids was studied using reflectance spectra, and their relationships with meteorites were established. Our results indicate that asteroids have mineral diversity, and their meteorite analogues are complex and diverse, the existing asteroid spectral classification system needs to be improved.
Satellite on-orbit radiometric calibration is the key to ensuring remote sensing applications. The Moon, with no atmosphere, a smooth spectral curve, and stable reflectivity and emissivity, serves as an excellent radiation source for satellite on-orbit radiometric calibration — this is particularly necessary for atmospheric absorption bands. A large number of satellites are equipped with lunar observation capabilities, making lunar calibration an established trend. We have used the Moon as a radiation source to perform radiometric calibration for satellites such as Gaofen-4 and Jilin-1 across the visible to thermal infrared bands, significantly improving the quality of remote sensing data. Our results demonstrate that lunar calibration is of great value for enhancing the quantitative application of satellites and is indispensable for hyperspectral remote sensing.
Biography:
Prof. Dr. Wu Yunzhao is leading the Planetary spectroscopy and remote sensing group at Purple Mountain Observatory (PMO), Chinese Academy of Sciences (CAS). His background is geochemistry and remote sensing. His research interests are solar system exploration using remote sensing and spectroscopy, mainly including: 1) remote sensing of asteroids and Moon; 2) photometric model; 3) calibration and preprocess of remote sensing data; 4) planetary geology; 5) space weathering.