Impact of Satellite Constellations on Radio Astronomy Revealed by New Research
In a significant development, new research has shed light on the detrimental impact of satellite constellations on radio astronomy. It has been discovered that the increasing number of satellites, including SpaceX’s Starlink, are causing interference in the wavelength bands specifically reserved for radio astronomy. The research highlights the emission of low-frequency radio waves from the electronics present onboard Starlink satellites, which poses a potential threat to the field of astronomy.
Engineer Federico Di Vruno, affiliated with the SKA Observatory and the International Astronomical Union, has expressed that the latest study marks a crucial step in comprehending the impact of satellite constellations on radio astronomy. The research confirms previous speculations discussed during workshops on Dark and Quiet Skies, revealing that the radiation in question is indeed quantifiable.
As the skies above our planet continue to grow increasingly congested, the implications of satellites on the study of space become a growing concern. Currently, SpaceX leads the way with an estimated 4,365 small internet satellites in Earth’s orbit, with plans for thousands more. However, they are not alone in this endeavor, as companies like OneWeb already have over 600 satellites deployed, while Amazon aims to launch thousands more starting in 2024. This escalating trend further underscores the significance of addressing the impact of satellite constellations on our exploration and understanding of space.
Balancing Satellite Brightness: Addressing Concerns of Radio Astronomy
Acknowledging the apprehensions surrounding visible light pollution, SpaceX has proactively addressed the issue by developing a new satellite model with reduced brightness. However, this solution primarily caters to the concerns related to visible wavelengths and fails to fully consider the impact on radio astronomy, a significantly larger field of study. Consequently, the article examines the potential challenges that might emerge within the domain of radio astronomy.
The utilization of radio frequencies ranging from 10.7 to 12.7 gigahertz for satellite communication downlink has drawn concerns, particularly within Europe. Scientists have long suspected that satellites may emit unintended radio waves outside the designated frequency band. To delve deeper into this issue, engineer Federico Di Vruno and his team undertook a thorough investigation.
Leveraging the exceptional sensitivity of the LOw Frequency ARray (LOFAR), a network comprising approximately 20,000 strategically positioned radio antennas spread across 52 locations in Europe, the researchers closely monitored 68 satellites from the Starlink constellation. The outcome of their meticulous observations confirmed the presence of electromagnetic leakage, providing valuable insights into the magnitude of the problem at hand.
Astronomer Cees Bassa, associated with ASTRON, the esteemed Netherlands Institute for Radio Astronomy, has shared noteworthy insights derived from observations conducted using LOFAR. The research revealed the detection of radiation within the frequency range of 110 to 188 MHz emanating from 47 out of the 68 observed satellites. This discovery underscores the presence of emissions in the lower frequency range, further underscoring the implications for radio astronomy.
Unintentional Radio Emissions Threaten Protected Frequency Range for Radio Astronomy
A critical concern arises as unintentional radio emissions from satellite electronics have been identified within the frequency range of 110 to 188 MHz. Of particular significance is the inclusion of the protected band specifically allocated to radio astronomy (150.05 to 153 MHz) by the International Telecommunications Union. It should be noted that these emissions are unintended and do not violate any existing regulations. However, unlike the stringent restrictions imposed on electrical devices on Earth by the International Electrotechnical Commission, similar regulations do not apply to space.
While the current impact of these emissions remains relatively minor, it is crucial to recognize that this situation may not persist indefinitely. As the number of satellites emitting unintentional radio signals increases, the brightness and intensity of these emissions will likely escalate, posing a potential threat to the field of radio astronomy.
Encouraging progress has been made in finding a resolution to the issue of unintentional radio leakage from satellites. The researchers have reached out to SpaceX, which is actively engaged in developing measures to minimize or eliminate this unintended emission. While the current deployment of satellite constellations is still in its nascent stage, the early detection of this problem presents an opportunity to incorporate necessary adjustments in future designs. Additionally, it highlights the need for regulators to address the unexpected gap in official rules pertaining to satellite emissions.
Renowned astronomer Michael Kramer from the Max Planck Institute for Radio Astronomy and the Astronomische Gesellschaft in Germany emphasizes the significance of this study as an example of how technology development can have unforeseen effects on astronomy. In light of SpaceX’s proactive approach, astronomers now call for broad support from the entire satellite industry and regulators to address this issue effectively.
The research findings have been published in the esteemed journal Astronomy & Astrophysics, emphasizing the importance of interdisciplinary collaboration in tackling the unanticipated impact of technology on the field of astronomy.