Starlink is SpaceX’s satellite broadband project that will eventually see tens of thousands of satellites orbiting the Earth to deliver internet to every corner of the globe. So far, Elon Musk and his SpaceX firm have been given approval to launch 12,000 of the satellites, but the South African-born billionaire is hoping to get permission to send an additional 30,000 satellites into Earth’s orbit. This has left many astronomers unhappy, who rely on a clear view of the night to gather more data on the cosmos.
Many experts are concerned the plans could cause major light pollution and obstruct the view of the universe, making astronomy nearly impossible to do.
Jonathan McDowell, an astronomer at the Harvard-Smithsonian Centre for Astrophysics, told The Times: “There is a point at which it makes ground-based astronomy impossible to do.
“I’m not saying Starlink is that point. But if you just don’t worry about it and go another ten years with more and more mega-constellations, eventually you are going to come to a point where you can’t do astronomy anymore. And so let’s talk about it now.”
SpaceX said they will paint the satellites pitch black as to minimise light pollution, but that would not solve the problem of how they might effect radio astronomy.
Scientists use radio astronomy for a plethora of issues, including taking the first ever image of a black hole.
However, radio astronomy is also used to search for signs of life elsewhere in the universe.
Telescopes such as the five-hundred-meter Aperture Spherical radio Telescope (FAST) in China and the Canadian Hydrogen Intensity Mapping Experiment (CHIME), to name just two, search for radio signals from deep space.
These radio signals can be created by black holes forming, stars colliding and even an extraterrestrial race trying to communicate throughout the cosmos.
Earlier this year, the International Astronomical Union (IAU) said in a statement: “The scientific concerns are twofold. Firstly, the surfaces of these satellites are often made of highly reflective metal, and reflections from the Sun in the hours after sunset and before sunrise make them appear as slow-moving dots in the night sky.
“Although most of these reflections may be so faint that they are hard to pick out with the naked eye, they can be detrimental to the sensitive capabilities of large ground-based astronomical telescopes, including the extreme wide-angle survey telescopes currently under construction.
“Secondly, despite notable efforts to avoid interfering with radio astronomy frequencies, aggregate radio signals emitted from the satellite constellations can still threaten astronomical observations at radio wavelengths.
“Recent advances in radio astronomy, such as producing the first image of a black hole or understanding more about the formation of planetary systems, were only possible through concerted efforts in safeguarding the radio sky from interference.”
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