Giant Satellite Becomes One of the Brightest Objects in Night Sky, But Here's Why It Sparks Concerns Among Astronomers

Researchers have made an intriguing discovery - the unique brightness of the giant BlueWalker 3 satellite. On certain occasions, it outshines nearly all celestial bodies visible from Earth, except for a select few stars and planets.

Raising Alarms Over Night Sky's Future

In recent times, Nature reported the prototype satellite has garnered significant attention for becoming a prominent fixture in the night sky. This occurrence hints at a potential emerging trend, as numerous satellites may soon follow suit.

The satellite in question, the BlueWalker 3, was launched by AST SpaceMobile in September 2022 and has become the focal point of an extensive observation campaign.

Researchers have recently discovered that the BlueWalker 3, on certain occasions, outshines nearly all celestial bodies visible from Earth, except for a select few stars and planets. These findings have ignited concerns within the astronomical community.

They underscore the mounting unease surrounding the proliferation of private space endeavors in low-Earth orbit, raising questions about their impact on our nighttime sky and the potential disruption of critical research efforts.

Monitoring BlueWalker 3

A team of scientists affiliated with the International Astronomical Union's Center for the Protection of the Dark and Quiet Sky from Satellite Constellation Interference (CPS) meticulously monitored BlueWalker 3 for 130 days.

The satellite's remarkable feature lies in its substantial antenna array, spanning nearly 700 square feet, making it the largest among commercial satellites in low-Earth orbit. This expansive array possesses the unique ability to reflect sunlight, resulting in periodic bursts of brightness.

These fluctuations are influenced by various factors, including the satellite's relative positioning to the sun and its viewing angle. The CPS team conducted their observations from multiple locations, including Chile, the United States, Mexico, New Zealand, the Netherlands, and Morocco.

The study's co-author, Siegfried Eggl, emphasized that the research findings reveal an ongoing trend in the deployment of larger and brighter commercial satellites, raising notable concerns. This concern is particularly pertinent considering the extensive plans for launching numerous such satellites in the upcoming years.

While these satellites have the potential to improve communication capabilities, Eggl stressed the importance of taking measures to minimize their disruptive impact on scientific observations. AST SpaceMobile's ambitious vision includes the deployment of around 100 cellular broadband satellites, all designed based on the BlueWalker 3 model.

SpaceX, known for its extensive Starlink satellite constellation, has been experimenting with dark coatings on its satellites in an attempt to reduce their light reflection. However, the success of these efforts has been limited. This concern has been a persistent issue for astronomers, who find the brightness of these satellites problematic.

As a result, Engadget reported that the researchers argue in their paper that ground-based observatories must devise strategies to avoid these artificial constellations and continue their work effectively.

The challenges posed by commercial satellites like BlueWalker 3 extend beyond visibility concerns. They also bring the threat of interference with radio astronomy.