P. Mahanti, M. S. Robinson, D. Humm, R. Wagner, Nick Estes, Jean-Pierre Williams
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引用次数: 0
Abstract
Lunar permanently shadowed regions (PSRs) never see direct sunlight and are illuminated only by secondary illumination - light reflected from nearby topography. The ShadowCam imaging experiment onboard the Korea Pathfinder Lunar Orbiter is acquiring images of these PSRs. We characterize and discuss the nature of secondary illumination for the Shackleton PSR from ShadowCam radiance-calibrated images. We also use modeling to understand the magnitude and direction of the secondary illumination. Results from our analysis highlight the non-homogeneous, dynamic, and complex nature of PSR secondary lighting. Knowledge of the direction of the secondary illumination is crucial for reli-able interpretation of contrasts observed in ShadowCam images. This preliminary analysis of the floor of Shackleton crater from images acquired over multiple secondary illumination conditions does not reveal indications of exposed surface ice, even though temperatures are constantly below 110K.
期刊介绍:
JASS aims for the promotion of global awareness and understanding of space science and related applications. Unlike other journals that focus either on space science or on space technologies, it intends to bridge the two communities of space science and technologies, by providing opportunities to exchange ideas and viewpoints in a single journal. Topics suitable for publication in JASS include researches in the following fields: space astronomy, solar physics, magnetospheric and ionospheric physics, cosmic ray, space weather, and planetary sciences; space instrumentation, satellite dynamics, geodesy, spacecraft control, and spacecraft navigation. However, the topics covered by JASS are not restricted to those mentioned above as the journal also encourages submission of research results in all other branches related to space science and technologies. Even though JASS was established on the heritage and achievements of the Korean space science community, it is now open to the worldwide community, while maintaining a high standard as a leading international journal. Hence, it solicits papers from the international community with a vision of global collaboration in the fields of space science and technologies.