Radio Astronomers Challenge Satellite Mania to Save the Universe

Radio astronomy’s enchanting journey began in the 1930s when Karl Jansky, a Bell Telephone Laboratories engineer, stumbled upon radio waves from the Milky Way. This discovery unwittingly ushered in an era where humanity could gaze into the universe through clouds and dust—unhindered by the limitations of optical telescopes. Over time, with the help of equipment from post-World War II military surplus, our understanding rapidly evolved, giving birth to breakthroughs like pulsars, quasars, and cosmic microwave background radiation. Today’s titans of radio astronomy, from the 500-meter Aperture Spherical Telescope in China to the vast Square Kilometre Array, continue to unravel the universe’s mysteries.

An Unforeseen Jam

In pursuing cosmic clarity, radio astronomers now face a looming challenge: satellite interference. Recently, the Low Frequency Array Radio Telescope (LOFAR) detected radio signals from satellites previously thought silent. Contrary to planned communications, these signals stem from emissions within restricted frequency bands, leaking from internal electronic systems of satellites. Dr. Emma van der Wateren sounded the alarm, highlighting how these unintended electromagnetic emissions jeopardize the stillness of the radio skies, vital for hearing the universe’s whispers.

The Unsanctioned Symphony

The real concern isn’t a single beacon in the sky; it’s the throbbing cacophony created by thousands of satellites, with plans for many more. As companies like SpaceX and Amazon race to blanket Earth with satellite internet, the resultant ‘radio noise’ threatens to drown the softly spoken secrets of the cosmos. In some cases, this noise rivals, or even overpowers, naturally occurring signals from celestial objects. Light pollution dims the night sky; radio pollution now risks obscuring our cosmic radio frequencies.

The Flaw in the Rules

Currently, no international regulations dictate satellite emissions, despite Earth-based electronics abiding by stringent interference standards. SpaceX’s satellites navigate the legal void unobstructed, leaving radio astronomers like captains without compasses, trying to chart invisible reaches of space amid swelling interference.

Uniting for Change

However, hope glimmers as radio astronomers gain a seat in CISPR, the International Special Committee on Radio Interference. This inclusion marks a milestone, empowering astronomers in shaping policies that could silence the disruptive hum of unintended emissions. As new telescopes like the Square Kilometre Array and others join our cosmic toolkit, timing is paramount. Listening to the universe across all wavelengths is akin to appreciating a symphony in its entirety. Losing radio access risks silencing one of the orchestra’s vital sections.

According to Universe Today, radio astronomers worldwide are rallying the possibility of a chorus without dissonance. As the cosmos remains ever watchful, global unity may ensure its stories continue to echo through radio waves, unmarred by interference.

Meet the Author

Mark Thompson, a science communicator and writer, has devoted his career to making science accessible. Known for his exuberant approach, Mark has been involved with BBC Stargazing LIVE and his acclaimed Spectacular Science theatre show. His 2025 ventures include a new podcast Cosmic Commerce and a book ‘101 Facts You Didn’t Know About Deep Space’. In 2018, the University of East Anglia acknowledged his contributions with an Honorary Doctorate.