Five more are due to join the unusually reflective prototype satellites later this week, which shine brighter than nearly any star in the sky. Astronomers warn that an increasing number of bright objects in the night sky could seriously hinder their research and even limit their ability to spot asteroids heading toward Earth.
Texas-based AST SpaceMobile launched the first Blue Walker 3 satellite in 2022, but it drew immediate criticism from astronomers who discovered that the satellite was brighter than all but seven stars in the night sky.
AST SpaceMobile plans to launch a total constellation of around 100 satellites to provide mobile phone connectivity around the world. The satellites’ unusual reflectivity — much higher than most communications satellites — comes from the fact that they are equipped with a 64-square-meter reflector antenna that inadvertently acts like a mirror for visible light.
The company press release The company was scheduled to launch its first five commercial satellites, called Bluebirds, from Cape Canaveral, Florida, on September 12. The company said last year that it was exploring options to reduce its impact on astronomy, but did not respond to a request for an interview. New Scientist About the latest release.
Grant Tremblay The growing constellation of satellites in low Earth orbit “is really an existential issue for astronomy,” said the researcher at Harvard University and the Smithsonian Center for Astrophysics in Massachusetts, who is also vice president of the American Astronomical Society. AST SpaceMobile is a concern for astronomers because of its incredibly reflective design, but it’s by no means the only one, he said. Internet company Starlink is another company whose satellites are causing concern.
“In astronomy, things are clearly getting worse,” Tremblay said. “I worry that we’re in danger of losing the sky.”
Tremblay said projects such as the Vera C. Rubin Observatory, under construction in Chile and set to begin observing the sky in 2025, would see bright streaks marring images as the satellite crosses the field of view.
“If a frame is contaminated by, say, a Starlink flight, it becomes useless; it has to be thrown away,” he says. “The observatories will continue to function; great science will continue to be done. But as we start heading towards a regime with hundreds or thousands of reflective satellites of this size or larger in orbit, efficiency can fall off exponentially. We’re entering a completely unsustainable regime with no regulatory structure whatsoever.”
Tremblay sees this as a loss not just for science, but for the wider society: “We have got back this incredibly magical image of the universe on an unimaginable scale. There’s something about it that brings people together and inspires them. If we were to lose that, I think it would be a social catastrophe.”
To solve the problem, astronomers may need to place more telescopes in space beyond crowded orbits, but the cost and complexity of doing that makes that impossible in most cases, he says.
Some warn that losing our astronomical capabilities could put humanity at risk. Ian Carneri Researchers at the European Space Agency say that projects like NASA’s DART spacecraft have improved our ability over the decades to spot Earth-bound asteroids and divert them. “In the future, asteroids may become harder to find,” they say. [because of reflective satellite constellations]”That’s true,” he says.
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Source: www.newscientist.com