High-precision light curves of geostationary objects: The PHANTOM ECHOES 2 RPO campaign

Paul Chote; Robert Airey; James McCormac; Don Pollacco; Richard West; Krzysztof Ulaczyk; Martin J. Dyer; Alexander Agathanggelou; William Feline; Simon George; Calum Meredith; Grant Privett

doi:10.1016/j.asr.2025.05.026

arXiv · 2506.01549

High-precision light curves of geostationary objects: The PHANTOM ECHOES 2 RPO campaign

Paul Chote·Robert Airey·James McCormac·Don Pollacco·Richard West·Krzysztof Ulaczyk·Martin J. Dyer·Alexander Agathanggelou·William Feline·Simon George·Calum Meredith·Grant Privett

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Abstract

We present results from an extensive optical observation campaign that monitored the Geostationary satellites Intelsat 10-02, Mission Extension Vehicle 2, Thor 5, Thor 6, Thor 7, and Meteosat 11 over a 14 week period that covered the proximity operations and docking of Mission Extension Vehicle 2 with Intelsat 10-02. High-cadence single-color photometric observations are supplemented with targeted multi-color observations, high resolution imaging, and passive radio frequency positioning obtained using complementary facilities. The photometric signatures of the six targets are presented in the form of two-dimensional color maps. A selection of interesting features are investigated in further detail, including a rapid glinting behavior in Thor 6; a brightening event from Meteosat 11; using glints to constrain the unresolved positions of Intelsat 10-02 and MEV-2; changes in the photometric signature of Intelsat 10-02 before and after docking; and signatures of attitude changes and maneuvering in the light curves of MEV-2. A detailed description of the photometric data reduction pipeline is also presented, with a focus on details that must be considered when aiming for sub-percent photometric precision.

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Paul Chote, Robert Airey, James McCormac, Don Pollacco, Richard West, Krzysztof Ulaczyk, Martin J. Dyer, Alexander Agathanggelou, William Feline, Simon George, Calum Meredith, Grant Privett. 2025-06-02. High-precision light curves of geostationary objects: The PHANTOM ECHOES 2 RPO campaign. https://doi.org/10.1016/j.asr.2025.05.026

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