Physical characterization of Earth's quasi-satellite 2025 PN7
Abstract
A hypothetical origin as lunar ejecta for Earth's quasi-satellites (QS) has gained initial support in recent years, but there is scarce photometric and/or spectroscopic data to support the premise due to the rare observational windows to obtain such data for these small objects. One of the key pieces of evidence supporting the lunar-origin hypothesis, the lunar-like, very red reflectance spectrum of QS (469219) Kamo'oalewa, was recently found to be flawed. We present reflectance spectroscopy of Earth's QS 2025~PN7 obtained with FORS2 at UT1-Antu of the ESO Very Large Telescope. This is only the second QS that has ever been characterized, the first being (469219) Kamo'oalewa, the sample-return target of the Tianwen-2 mission. Our results indicate that 2025~PN7 exhibits a near-solar, flat visual spectrum, most consistent with the B-type in the Bus-DeMeo taxonomy. Our results therefore still support an asteroid-belt origin for most of Earth's QSs. The lunar-ejecta hypothesis can only be formally rejected with a larger sample of spectroscopically characterized QSs.
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BibTeX
@misc{fedorets2026physical,
title = {{Physical characterization of Earth's quasi-satellite 2025 PN7}},
author = {Grigori Fedorets and Zuri Gray and Mikael Granvik and Eric MacLennan},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.17981},
eprint = {2610.17981},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.17981},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Physical characterization of Earth's quasi-satellite 2025 PN7
AU - Grigori Fedorets
AU - Zuri Gray
AU - Mikael Granvik
AU - Eric MacLennan
PY - 2026
DA - 2026/10/13
PB - arXiv
DO - 10.48550/arxiv.2610.17981
UR - https://arxiv.org/abs/2610.17981
AB - A hypothetical origin as lunar ejecta for Earth's quasi-satellites (QS) has gained initial support in recent years, but there is scarce photometric and/or spectroscopic data to support the premise due to the rare observational windows to obtain such data for these small objects. One of the key pieces of evidence supporting the lunar-origin hypothesis, the lunar-like, very red reflectance spectrum of QS (469219) Kamo'oalewa, was recently found to be flawed. We present reflectance spectroscopy of Earth's QS 2025~PN_7 obtained with FORS2 at UT1-Antu of the ESO Very Large Telescope. This is only the second QS that has ever been characterized, the first being (469219) Kamo'oalewa, the sample-return target of the Tianwen-2 mission. Our results indicate that 2025~PN_7 exhibits a near-solar, flat visual spectrum, most consistent with the B-type in the Bus-DeMeo taxonomy. Our results therefore still support an asteroid-belt origin for most of Earth's QSs. The lunar-ejecta hypothesis can only be formally rejected with a larger sample of spectroscopically characterized QSs.
ER -