Detection of intended and unintended emissions from Starlink satellites in the SKA-Low frequency range, at the SKA-Low site, with an SKA-Low station analog

Abstract

Intended and unintended radio emissions from satellites can interfere with sensitive radio telescopes in the frequency ranges of key experiments in astrophysics and cosmology. We detect strong intended and unintended electromagnetic radiation from Starlink satellites at the site of the future SKA-Low facility in Western Australia, using an SKA-low prototype station known as the Engineering Development Array version 2 (EDA2). We aim to show that Starlink satellites are easily detectable utilising a configuration of low frequency radio antennas representative of an SKA-Low 'station' and that our results complement similar findings with the LOFAR telescope. Utilising the EDA2 at frequencies of 137.5 MHz and 159.4 MHz, we detect trains of Starlink satellites on 2023-03-17/18 and 2021-11-16/17, respectively, via the formation of all-sky images with a frequency resolution of 0.926 MHz and a time resolution of 2 s. Time differencing techniques are utilised to isolate and characterise the transmissions from Starlink and other satellites. We observe Starlink satellites reaching intensities of $10^6$ Jy/beam, with the detected transmissions exhibiting a range of behaviours, from periodic bursts to steady transmission. The results are notable because they demonstrate that Starlink satellites are detected in the SKA-Low frequency range, transmitting both intentionally and unintentionally. Follow-up work and discussion are needed to identify the cause of this unintentional radiation as it has the potential to interfere with SKA-Low science. Our results indicate that both intended and unintended radiation from Starlink satellites will be detrimental to key SKA science goals without mitigation. Continued conversation with SpaceX could potentially result in future mitigations which the EDA2 instrument could efficiently monitor and characterise at the SKA-Low site.

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Cited by in corpus (10)

• The Growing Impact of Unintended Starlink Broadband Emission on Radio Astronomy in the SKA-Low Frequency Range
• Near-field imaging of local interference in radio interferometric data: Impact on the redshifted 21 cm power spectrum
• Broadband Polarized Radio Emission Detected from Starlink Satellites Below 100 MHz with NenuFAR
• Altitude Estimation of Radio Frequency Interference Sources via Interferometric Near Field Corrections
• TABASCAL: Removing multi-satellite interference from radio interferometry observations
• Satellite Impact on Astronomical Observations Based on Elliptical Orbit Model
• The impact of lunar topography on the 21-cm power spectrum for grid-based arrays : Insights for the Dark-ages EXplorer (DEX)
• A Multi-Site Study of Radio Environment for Cosmology Experiments
• Mitigating incoherent excess variance in high-redshift 21 cm observations with multi-output cross-Gaussian process regression
• SNIFFLES I: Intended Emission, Unwanted Emission, and Unintended Radiation from Low-Earth Orbiting Satellites Impacting Radio Astronomy from 1-26 GHz