In the last few years, the space community has raised concerns about the growing deployment of constellations of communication satellites in low-Earth orbit (LEO).
Satellite constellations, such as those launched by SpaceX (Starlink) and OneWeb, can significantly improve global communication services.
However, there are some concerning downsides. The technology can impede astronomical universe studies by causing light pollution, leaving satellite trails, and leaking radio signals.
An international team of scientists and astronomers has now evaluated the influence of a large BlueWalker 3 prototype satellite on astronomical observations.
“The night sky is a unique laboratory that allows scientists to conduct experiments that cannot be done in terrestrial laboratories. Astronomical observations have provided insights into fundamental physics and other research at the boundaries of our knowledge and changed humanity’s view of our place in the cosmos. The pristine night sky is also an important part of humanity’s shared cultural heritage and should be protected for society at large and for future generations,” said Dave Clements, from the Department of Physics at Imperial College London, in an official release.
An international campaign to track BlueWalker 3 prototype satellite
AST SpaceMobile launched the BlueWalker 3 into low-Earth orbit on September 10, 2022.
Observations in the weeks following the BlueWalker 3 prototype satellite's launch revealed that it was one of the most bright objects visible in the night sky.
Astronomers find this matter deeply troubling, particularly concerning their ability to accurately observe stars, galaxies, and other celestial entities.
This brightness prompted the researchers to analyze how the satellite would affect astronomy thoroughly.
An international campaign was initiated involving professional and amateur astronomers who conducted night-sky observations from various locations worldwide. These observations were mainly conducted in Chile, the United States, Mexico, Aotearoa, New Zealand, the Netherlands, and Morocco.
Impact on radio astronomy
They recorded the brightness of BlueWalker 3 for a total of 130 days.
“The newly released data show an abrupt increase coinciding with the complete unfolding of the antenna array, which at 64 square meters is the largest commercial antenna system ever deployed into low-Earth orbit,” mentioned the release.
The researchers also calculated the satellite's predicted path over time to minimize any interference in the planned observations and, at the absolute least, to know where they were in the data.
The findings indicated that the BlueWalker 3 might affect radio astronomy and visible observations.
This is due to the satellite's operation based on wavelengths similar to those monitored by radio telescopes.
"BlueWalker 3 actively transmits at radio frequencies that are close to bands reserved for radio astronomy, and existing observatory protections from radio interference may not be sufficient,” said Mike Peel, a researcher in the Department of Physics at Imperial.
Despite certain telescopes being situated in regions designated as radio-quiet zones, the regulations established to protect these zones currently apply exclusively to land-based transmitters, leaving them exposed to satellite signals.
In the upcoming years, space startups are preparing to deploy numerous satellite constellations to enhance broadband services and expand their coverage to various regions across the globe.
“Further research is therefore required to develop strategies for protecting existing and upcoming telescopes from the numerous satellites planned for launch over the next decade,” added Peel.
This study is conducted by the IAU Centre for the Protection of the Dark and Quiet Sky from Satellite Constellation Interference (CPS).
The results were reported in the journal Nature.
Originally published on Interesting Engineering : Original article