The Growing Number of Satellites in Orbit Could Soon Make Telescopes Obsolete
Featured image: Satellite streaks crossing a deep-field astronomical image; credit: NOIRLab/NSF/AURA
The number of satellites in Earth orbit could soon reach a threshold where ground-based astronomy becomes impossible, according to a peer-reviewed study from the European Southern Observatory published in Astronomy & Astrophysics. If the total satellite population exceeds 100,000, every astronomical image taken from the planet’s surface would be corrupted by artificial streaks and light pollution.
Currently, approximately 14,000 satellites orbit Earth. But several pending applications could drive that number far higher. Reflect Orbital has proposed a constellation of 50,000 bright orbital mirrors, each 18 by 18 metres (59 by 59 feet), designed to reflect sunlight for commercial illumination. The company’s satellites would appear brighter in telescope beams than the full moon and brighter than Venus to the naked eye. Separately, SpaceX has filed plans for orbital data centres with solar panels up to 70 metres (230 feet) across, potentially involving up to 1 million satellite structures.
“We can reach conditions where basically, there is no point in operating the telescopes anymore because all the data will be corrupted. All. 100 percent,” said Olivier Hainaut, ESO astronomer and lead author of the study.
ESO and hundreds of scientific organisations have filed formal objections to both proposals. The study simulated varying numbers and brightness levels of satellites on observations from ESO’s Very Large Telescope in Chile’s Atacama Desert, one of the darkest and most remote observing sites on Earth. Even at that location, a sky brightening of just 10 percent increases exposure times by 10 percent. At the levels proposed by Reflect Orbital, sky brightness above the telescope could increase by up to 300 percent.
Robert Massey of the Royal Astronomical Society called the situation “catastrophic” for astronomy and warned of broader societal consequences. “The public has not signed up for having an entirely transformed sky,” he said. “If it’s agreed by the FCC, this will be deeply regrettable. This will say that we are in a world where large corporations can determine the view of the sky above our heads.”
The regulatory landscape offers little recourse. The 1967 Outer Space Treaty requires space to be used “for the common good of humankind,” but was written before the era of private commercial megaconstellations. The U.S. Federal Communications Commission does not currently require environmental impact statements for satellite licensing applications. A recent reduction in regulatory burden under the Trump administration has further streamlined approvals for large constellation operators.
To preserve ground-based astronomy, Hainaut’s modelling finds that satellites must be fainter than magnitude 7, significantly dimmer than most current and proposed designs. Without such constraints, astronomers warn that the coming decade could mark the end of humanity’s ability to study the universe from Earth’s surface.
Source: 1ban.news – Space Desk