TY - JOUR
T1 - Preliminary Characterization of Secondary Illumination at Shackleton Crater Permanently Shadowed Region from ShadowCam Observations and Modeling
AU - Mahanti, Prasun
AU - Robinson, Mark Southwick
AU - Humm, David Carl
AU - Wagner, Robert Vernon
AU - Estes, Nicholas Michael
AU - Williams, Jean Pierre
N1 - Publisher Copyright:
© This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (https://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
PY - 2023
Y1 - 2023
N2 - 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.
AB - 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.
KW - Danuri
KW - Korea Pathfinder Lunar Orbiter (KPLO)
KW - Shackleton crater
KW - ShadowCam
KW - permanently shadowed region
KW - secondary illumination
UR - http://www.scopus.com/inward/record.url?scp=85189461186&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85189461186&partnerID=8YFLogxK
U2 - 10.5140/JASS.2023.40.4.131
DO - 10.5140/JASS.2023.40.4.131
M3 - Article
AN - SCOPUS:85189461186
SN - 2093-5587
VL - 40
SP - 131
EP - 148
JO - Journal of Astronomy and Space Sciences
JF - Journal of Astronomy and Space Sciences
IS - 4
ER -