Starlink Signals Drown Out Cosmic Whispers

New Study Reveals Satellite Emissions Threaten Radio Astronomy Discoveries

Groundbreaking research from Curtin University has exposed a significant interference issue for radio astronomy, with Starlink satellites emitting unintended signals that could impede the study of the universe.

Unwanted Radio Noise

The world’s most extensive survey of low-frequency satellite radio emissions, conducted by Curtin University researchers, found that Starlink satellites are a major source of interference. These unintended signals, leaked from onboard electronics, risk masking the faint radio waves essential for astronomical observations and discoveries.

Starlink’s Growing Footprint

Researchers at Curtin’s Institute for Radio Astronomy (CIRA) specifically examined SpaceX’s Starlink constellation, the largest in orbit with over 7,000 satellites during the study. Their analysis of 76 million sky images, gathered using a prototype for the Square Kilometre Array (SKA) — the future most sensitive radio telescope — revealed a concerning trend.

Detecting the Interference

PhD candidate and lead researcher, Dylan Grigg, reported the detection of over 112,000 radio emissions originating from 1,806 Starlink satellites. This comprehensive catalog highlights Starlink as the most frequent and immediate potential disruptor for radio astronomy. “In some datasets, we found up to 30 per cent of our images showed interference from a Starlink satellite,” Mr. Grigg stated.

Signals in Protected Bands

The problem extends beyond the sheer number of satellites. Mr. Grigg noted that some Starlink satellites were detected emitting signals in frequency bands specifically protected for radio astronomy, such as 150.8 MHz. “Because they may come from components like onboard electronics and they’re not part of an intentional signal, astronomers can’t easily predict them or filter them out.”

“Current International Telecommunication Union regulations focus on intentional transmissions and do not cover this type of unintended emission. Starlink isn’t the only satellite network, but it is by far the biggest and its emissions are now increasingly prominent in our data.”

—Professor Tingay, University Researcher

Professor Tingay emphasized the need for updated international regulations to manage the impact of such technologies on radio astronomy. “We hope this study adds support for international efforts to update policies that regulate the impact of this technology on radio astronomy research, that are currently underway.” He also clarified that Starlink is not currently in violation of existing rules and that discussions with SpaceX have been productive.

The future of astronomical discovery, including answering fundamental questions about the universe’s origins and dark matter, relies on maintaining radio quiet zones. “We’re standing on the edge of a golden era where the SKA will help answer the biggest questions in science… But it needs radio silence to succeed. We recognise the deep benefits of global connectivity but we need balance and that starts with an understanding of the problem, which is the goal of our work,” Professor Tingay explained.

The findings were published in the journal *Astronomy and Astrophysics* under the title ‘The Growing Impact of Unintended Starlink Broadband Emission on Radio Astronomy in the SKA-Low Frequency Range’.