Introduction
Lunar Season Calculator
As lunar seasons do not correspond to consistent calendar dates, this Excel workbook tool was developed to allow users to efficiently explore expected future seasonal cycles using one of two methods. The first is a direct lookup of subsolar latitude and hemispheric seasonal state for a user-defined date. The second allows the user to specify a subsolar latitude range and temporal search window and will return all date ranges for which the subsolar latitude criterion is met. Both options provide plots that place the results in context.
Subsolar latitude values were calculated for 00:00:00 UTC on each day between 1 Jan 2020 and 31 Dec 2029 using the SpiceyPy subslr module and the following kernels: naif0012.tls (LSK), de438.bsp (SPK), moon_080317.tf (FK), pck00010.tpc (PCK), and moon_pa_de421_1900-2050.bpc (PCK) [3, 4]. Reported values have about ±0.04° uncertainty due to the maximum progression of the true value over the course of 24 hours; this is assumed to be higher than the degree of precision achieved with SPICE kernels over the decade the calculations cover.
The Lunar Season Calculator was developed by Sam Cartwright and Jordan Bretzfelder. We thank Dr. David Kring and LPI for their interest in hosting the tool. We are also greatly indebted to Andrew Annex and the other contributors to the SpiceyPy project. For questions or comments, please contact scartwright@nevada.unr.edu.
Lunar Surface Innovation Consortium
The purpose of the Lunar Surface Innovation Consortium (LSIC) is to harness the creativity, energy, and resources of the nation to help NASA keep the United States at the forefront of lunar exploration.
LSIC operates in collaboration with the NASA Space Technology Mission Directorate under the Lunar Surface Innovation Initiative (LSII). LSIC fosters communications and collaborations among academia, industry, and Government. Members have expertise in LSII key capability areas.
