Multispectral imaging and hyperspectral scanning of the first dissection of Apollo core 73002: Preliminary results

Abstract:

The Apollo Next Generation Sample Analysis (ANGSA) initiative was designed to examine a set of Apollo samples that were reserved for future analysis, many of which were preserved in unique containers or collected in special environments (Shearer et al., 2020). Among these is the core samples 73002, which was collected on a landslide deposit at sampling station 3 in the Taurus-Littrow Valley during the Apollo 17 mission.

The core is being disassembled (“dissected”) by members of the JSC curatorial staff. Among the many measurements being made during this preliminary examination of the core is the near infrared multispectral imaging and hyperspectral profiling.

We obtained a multispectral image of the whole core and a hyperspectral profile along the center of the core during the first dissection pass of core 73002. We find that both the multispectral image and hyperspectral profile show a systematic darkening and reddening effect from bottom to top of the core due to space weathering on lunar surface. FeO and TiO₂ contents derived from the multispectral image both show homogeneous distributions along the core, indicating no compositional stratigraphy was sampled. An optical maturity (OMAT) profile was also calculated to investigate the regolith maturity variation along the core. A high maturity zone was observed within the top 14 cm of the core, suggesting a regolith gardening depth of 14 cm, and the corresponding regolith gardening time is about 61 million years based on the equation derived by Morris (1978).

As the dissection of the core proceeds, we will collect additional spectral records. Our spectral measurements of the core can contribute to the documentation of Apollo core samples and provide significant ground truth for remote sensing datasets.

References:

Morris 1978, 9^th LPSC, Vol. 9, pp. 1801-1811

Shearer et al. 2020, 51^st LPSC, Abstract 1181