Starlink leaked radio signals up to 10,000 times stronger than cosmic dawn target, Curtin study finds

A Curtin University study published in Astronomy & Astrophysics found that SpaceX’s Starlink satellites are leaking unintended radio emissions up to 10,000 times stronger than the faint hydrogen signals the €2.1 billion Square Kilometre Array Low (SKA-Low) telescope is built to detect. With up to 30% of observation images contaminated, the world’s most sensitive radio telescope may struggle to study the universe’s first stars.

Bottom line — The SKA-Low’s most sensitive science may be impossible unless SpaceX redesigns its satellites or regulations catch up.

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• The Curtin-led team analyzed 76 million images from an SKA-Low prototype station over 29 days, cataloguing 112,534 radio emissions from 1,806 unique Starlink satellites across 73–235 MHz — the exact range SKA-Low needs for its epoch-of-reionisation science, per the paper.
• Leaked emissions were detected inside two frequency bands protected by the International Telecommunication Union (ITU) — 73–74.6 MHz (13 satellites) and 150.05–153 MHz (703 satellites) — where no signals should exist, reported Astronomy Magazine.
• The source of the unintended electromagnetic radiation (UEMR) is unknown, but Grigg said it likely comes from onboard electronics like propulsion or avionics, making it unpredictable and impossible to subtract via modelling.
• ITU regulations cover only intentional transmissions, leaving UEMR in a regulatory grey zone; study co-author Steven Tingay said “Starlink is not violating current regulations, so is doing nothing wrong,” per ICRAR.
• SpaceX has previously mitigated optical brightness with visors and signed a coordination agreement with the U.S. National Science Foundation in 2019, but those measures do not address low-frequency hardware leakage, the study notes.
• A separate LOFAR study found second-generation Starlink satellites emit UEMR 32 times stronger than their predecessors, per Astronomy Magazine, suggesting the problem is worsening as the constellation grows (over 7,000 satellites during the study, with 477 launched in four months).
• Researchers said discussions with SpaceX have been “constructive” and the company is open to dialogue on future hardware changes, but algorithmic mitigation remains “embryonic” and could demand computing power rivaling the science itself, according to Gadget Review.

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