In the coming years, a number of next-generation observations and arrays will be operational. These features will make major contributions to many areas of astronomy: exploring the mysteries of the early universe, studying gravitational waves, determining the role of dark matter and dark matter in global evolution, and direct image “Earth-like” exoplanets.
Unfortunately, this revolutionary development in astronomy could go against another big project: the formation of mega-stars. Because of this, the SKA, which oversees the International Square Kilometer Array (SKA), The organization (SKAO) is urging that corrective measures be taken so that satellites do not interfere with its radio observations once they are operational.
Conceived in the 1990s, the square kilometer array is an international collaboration aimed at building and operating the world’s largest radio observatory. The project involves thousands of scientists and engineers from 15 countries and three Pathfinder facilities in Western Australia, Australia and South Africa – including the Australian Australian Square Kilometer Array Pathfinder, the Morchison Widefield Array (MWA) and the Merkel.
Due to the fact that they use the same frequency range as radio telescopes, there is always concern about the possibility of radio frequency interference (RFI) from satellites. In the past, radio observatories have been able to make observations in the same frequency range due to the low number of (visible) satellites in geostationary orbit (GSO) around the Earth and their fixed position.
1st Gust. As of May 1, 2020, there are 2,787 satellites operating in orbit around the Earth. But in the coming years, that number is projected to rise to 6,400, with some estimates that it could reach 100,000. This is expected to significantly interfere with radio telescopes, especially as the SKA-Mid telescope will soon be built in South Africa.
This telescope array consists of 197-radio dishes that scan the sky in the mid-frequency range. Of particular concern is the presence of satellite signals in the Band 5B range, which is similar to some of the receivers of the SKA-Mid Telescope. SKAO’s low frequency telescope in Western Australia, which uses a variety of antenna techniques, was not included in this analysis.
A thorough analysis was then performed of the SKAO recommendations that quantified the proposed influence of the constellations of the satellites, such as the proposed suggestions of SpaceX. Starlink Constellation – will be in the coming years. Overall, SKAO analysis focuses on three main categories. First, they are considered potential Physical damage.
For this category, the concern is that the intense radio signals from the satellites may have the potential to illuminate SKA’s recipes directly. However, his study did not rule out these concerns. Second, there is the possibility Instrument saturation, Because very strong radio interference can saturate the receiver system to the point where all other signals are submerged.
This frequency will lead to loss of all data in the band, thus rendering the receiver temporarily useless. Short-term saturation is expected during the first phase of constellation deployment (for 400 satellites). For 100,000 satellites, saturation will remain constant without mitigation measures. Finally, there it is Scientific effect Caused by large constellations.
Despite the small estimated size of 6,400 satellites, S.K.A.O. Assume that all astronomical observations within the frequency range of satellite broadcasts are subject to continuous loss of sensitivity. This effect will be most significant for the study of complex organic and extragalactic molecules (others). Such as S.K.A. Director of Science Dr. Ro. Robert Branun, S.K.A.O. The statement explains:
“There is a strong scientific and public interest in identifying the origin of life on Earth, and one of the most promising methods of finding it elsewhere in our galaxy is the discovery of complex prebiotic molecules, with spectrum signatures centered around 10. And 15 GHz. These are just some of the exciting science goals that are based on sensitive access to this frequency range. The possibility of losing sensitivity in this key frequency band is extremely worrying.“
This led analysts to several conclusions. Among them is the fact that satellites broadcasting in the band 5B range will produce interference that can result in a loss of sensitivity in that range. It is further speculated that astronomers will increase the time required for specific study objects in the sky to be clearly observed (a.k.a. integration time) by 70%.
In short, radio observatories will be able to run just over half of many observations in that band. The analysis also found that for larger stars (up to 100,000 satellites), the effect of SKA would be worse. In this case, they estimate that the band could experience up to 100% interference in the 5B range. Dr Bra did not say:
“The loss of observability at the top of the expected large overscript on a telescope would directly translate into lost science and it is possible that the most challenging experiments that would otherwise have been conducted would no longer be appropriate in these circumstances.”
The strategies they identify include ensuring that the satellite transmitters reach the SKAO. Do not show their beams near the dish. This will require a simple software modification that will instruct satellites to run away from their beam telescope site, SKAO insists, not affecting the star’s deployment, position or hardware.
Analysts assured that in order not to affect telecommunications and TV transmissions when crossing routes with GSO satellites, operators are already using this technology in compliance with international regulations. If followed, this strategy can reduce possible interference with the SKA-MID telescope by a factor of 10 and reduce the integration time increase by only 7%.
While interference at any level is regrettable, SKA indicated that some degree of compromise is needed. In the meantime, if all those who adhered to the recommendations of the analysis provided, it would be possible to keep the interference to a minimum. Pro. Philip Diamond, Director General of SKA:
“Thanks to our modeling work, the potential impact of satellite mega-stars on SKA is now understandable. We are building a state-of-the-art multi-billion euro research facility funded by taxpayers around the world, and we need to secure and maximize its ability to deliver innovation and new knowledge to humanity. “
In addition, they noted that the Astronomy Geographic Advantage (AGA) Act has already limited serious commercial incentives for companies targeting their beams toward the SKA-Mid site. The move, passed by the South African parliament in 2007, regulates how satellite operators can install land-based infrastructure to establish a “radio-quiet” zone in the vicinity of the SKA-Mid site.
Speaking of reductions, the recommendations were made six months after Elon Musk announced that future Starlink deployments would be to “DarkSet” satellites. Properly named, this design relies on darker phased arrays and parabolic antennas to reduce brightness by an estimated 55%. Musk’s firm commitment to ensuring his constellation won’t affect astronomy is what SKAO plans to capture!
Beyond SKA, the astronomical community has expressed concern about how planned satellite constellations will be taxed at the next pay generation. The Rubin Observatory – (formerly the Large Synoptic Survey Telescope (LSST) – and the Event Horizon Telescope (EHT) – has expressed concern that it could disrupt next-generation optical and radio features. !
In addition to the problem of radio interference, the possibility of thousands more satellites in orbit raises the issue of “space junk”. Currently, there are many earth-based and space-based strategies in overcoming these problems. However, this is likely to accelerate to ensure the sky and radio bands remain clear and unambiguous!
Further reading: S.K.A.
