Eric Pearce, University of Arizona Steward Observatory; Harrison Krantz, University of Arizona Steward Observatory; Adam Block, University of Arizona Steward Observatory; Brad Sease, Computational Physics, Inc; Mitchell Kirshner, University of Arizona System and Industrial Engineering
Keywords: multi-color photometry, SSA, UKIRT, WFCAM, UIST, SL-12 rocket bodies, HS-376, Centaur, Molniya
Abstract:
The characterization of deep space debris poses a significant challenge in Space Situational Awareness (SSA). To be most useful, characterization should provide actionable information quickly, even under non-ideal observing conditions. Multi-color photometry and the resultant color indices offer the potential to rapidly discriminate between debris and intact space objects such as rocket bodies and satellites. These multi-color techniques can also identify anomalous members of object groups and cue higher fidelity data collections and studies.
In this paper, we present the results from our 2020-2021 measurements campaign supplemented by further analysis from our previous 2016-2017 campaign. In 2017-2018, our team began developing and demonstrating rapid multi-color photometry techniques using the Russian SL-12 fourth stage rocket bodies (RB). We demonstrated that anomalous members of our rocket body cohort can be readily identified using only near-infrared (IR) color indices. During late 2020 and early 2021, our team expanded our previous characterization by using both the United Kingdom Infrared Telescope (UKIRT) Wide Field Camera (WFCAM) and the 1-5 mm Imager-Spectrometer (UIST). Specifically, we have expanded our data set to include:
more SL-12 fourth stage RBs increasing years-on-orbit range compared to our 2016-2017 campaign,
Centaur RBs of the same type as the returning RB cataloged as Near-Earth Object 2020 SO,
a selection of Molniya communication satellites including the -1K, 1T, -2, and -3 variants,
Russian FREGAT and SL-6 upper stage RBs in Molniya orbits,
intact payloads selected from satellites using the Boeing HS-376 busses.
Our new data set provides us with overlapping broadband IR colors and high-resolution spectra in those same color bands. We carefully chose our targets to include a mix of objects with known compositions to allow the development and evaluation of novel techniques to interpret our broadband near-IR photometry. The addition of Molniya payloads and RBs is a unique addition to existing literature since all previous published studies have focused on objects in geosynchronous orbits. For the first time, we can analyze near-IR photometry with the context of the full resolution near-IR spectra of same-type. We offer insight into refining the spectral bands of interest for characterization and provide an approach to improve rapid discrimination capabilities using substantially more efficient near-IR photometric techniques.
Date of Conference: September 14-17, 2021
Track: Non-Resolved Object Characterization