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arXiv · 2607.21812

Determination of Earth's Orbital Parameters Using Doppler Measurements

Gary Atkins·Marcus Leech·Daniel Marlow·Doug Yuill
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Abstract

Precision determinations of the parameters of Earth's orbit around the Sun using methods based on the Doppler shift of 21-cm emissions from the galaxy and the repetition rate of pulsar J0332+5434 are reported. The observed values and statistical errors for the orbital parameters for the 21-cm observations are semi-major axis $a = 1.00020 \pm 0.00015~{\rm au}$ and eccentricity $e= 0.017077 \pm 0.000077$. For the pulsar observations, the observed values are $a = 1.000034 \pm 0.000034~{\rm au}$ and $e=0.016667 \pm 0.000017$. The observations are based on a year-long campaign of daily drift-scan observations using a 12.8-m parabolic antenna and a receiver chain tuned to the 21-cm frequency band. The data used in the analysis are available for use in educational exercises in the supplementary material

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Gary Atkins, Marcus Leech, Daniel Marlow, Doug Yuill. 2026-07-23. Determination of Earth's Orbital Parameters Using Doppler Measurements. https://arxiv.org/abs/2607.21812

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