Orbit determination for non-cooperative low Earth orbit (LEO) objects undergoing continuous low-thrust maneuvers remains a significant challenge, particularly for large satellite constellations like Starlink. This paper presents a method that integrates the unscented transformation into a batch filtering framework with an optimized rho-minimum sigma points sampling strategy. The proposed approach uses a reduced dynamics model that considers Earth's non-spherical gravity and models the combined effects of low-thrust and atmospheric drag as an equivalent along-track acceleration. Numerical simulations under different measurement noise levels, initial state uncertainties, and across multiple satellites confirm the method's reliable convergence and favorable accuracy, even in the absence of prior knowledge of the along-track acceleration. The method consistently converges within 10 iterations and achieves 24 h position predictions with root mean square errors of less than 3 km under realistic noise conditions. Additional validation using a higher-fidelity model that explicitly accounts for atmospheric drag demonstrates improved accuracy and robustness. The proposed method can provide accurate orbit knowledge for space situational awareness associated with continuously maneuvering Starlink satellites.
This study aimed to perform the world's first robot-assisted telesurgery for lung resection in an animal model using Starlink (SpaceX) to address cost and latency issues associated with conventional telesurgery communication methods. A Saroa (Riverfield Inc) surgical robot with haptic feedback function was used in a swine model. The animal was located 1000 km away in Fukushima, Japan, while the surgeon console was located in Fukuoka, Japan. Starlink provided real-time video and data communication. Surgical parameters including safety, latency, and cost were evaluated. The surgery was completed in 2 hours 44 minutes. Average communication latency was approximately 130 milliseconds, with minor image disturbances occurring once every 5 minutes, potentially due to satellite switching or weather conditions. Despite these interruptions, the surgery was conducted safely. The successful performance of this telesurgery highlights the potential of low-cost and low-latency satellite communication systems to overcome barriers in telesurgery. These findings pave the way for broader telesurgery applications, particularly in underserved regions, and set the stage for further technical and clinical advancements in remote robotic surgery.
Genomic medicines are transforming the landscape of human health-but their promise risks being confined to the few. While science has entered the 21st century, most health systems remain unequipped to deliver one-time curative therapies. This essay calls for a global reckoning: what do we truly value in innovation, and how can we align systems, incentives, and ethics to democratize access? Drawing on real-world experience across four continents, it argues for a new social compact-embedding equity, rethinking value, and modernizing delivery-to ensure that the miracles of modern medicine become global, sustainable, and just.
The launch of a series of Starlink internet satellites on 3 February 2022 (S-36), and 7 July 2022 (S-49), coincided with the development of two-phase geomagnetic storms. The first launch S-36 took place in the middle of the moderate two-phase space weather storm, which induced significant technological consequences. After liftoff on 3 February at 18:13 UT, all Starlink satellites reached an initial altitude of 350 km in perigee and had to reach an altitude of ~550 km after the maneuver. However, 38 of 49 launched spacecrafts did not reach the planned altitude, left orbit due to increased drag and reentered the atmosphere on 8 February. A geomagnetic storm on 3-4 February 2022 has increased the density of the neutral atmosphere up to 50%, increasing drag of the satellites and dooming most of them. The second launch of S-49 at 13:11 UT on 7 July 2022 was successful at the peak of the two-phase geomagnetic storm. The global ionospheric maps of the total electron content (GIM-TEC) have been used to produce the ionospheric weather GIM-W index maps and Global Electron Content (GEC). We observed a GEC increment from 10 to 24% for the storm peak after the Starlink launch at both storms, accompanying the neutral density increase identified earlier. GIM-TEC maps are available with a lag (delay) of 1-2 days (real-time GIMs have a lag less than 15 min), so the GIMs forecast is required by the time of the launch. Comparisons of different GIMs forecast techniques are provided including the Center for Orbit Determination in Europe (CODE), Beijing (BADG and CASG) and IZMIRAN (JPRG) 1- and 2-day forecasts, and the Universitat Politecnica de Catalunya (UPC-ionSAT) forecast for 6, 12, 18, 24 and 48 h in advance. We present the results of the analysis of evolution of the ionospheric parameters during both events. The poor correspondence between observed and predicted GIM-TEC and GEC confirms an urgent need for the industry-science awareness of now-casting/forecasting/accessibility of GIM-TECs during the space weather events.
The large availability of Low Earth Orbit (LEO) satellite systems makes them useful beyond their original purposes, such as in positioning, where their signals can be passively used. In order to determine their potential for this purpose, newly deployed systems need to be investigated. This is the case with the Starlink system, which has a large constellation and is advantageous for positioning. It transmits signals in the 10.7-12.7 GHz band, the same as that of geostationary satellite television. Signals in this band are typically received using a low-noise block down-converter (LNB) and a parabolic antenna reflector. Regarding opportunistic use of these signals in small vehicle navigation, the dimensions of the parabolic reflector and its directional gain are not practical for tracking many satellites simultaneously. In this paper, we investigate the feasibility of tracking Starlink downlink tones for opportunistic positioning in a practical situation, when signals are received without a parabolic reflector. For this purpose, an inexpensive universal LNB is selected, and then signal tracking is performed to determine the signal and frequency measurement quality, as well as the number of satellites that can be tracked simultaneously. Next, the tone measurements are aggregated to handle tracking interruptions and to recover the traditional Doppler shift model. After that, the use of measurements in multi-epoch positioning is defined, and its performance discussed as a function of the relevant measurement rate and the required multi-epoch interval duration. The results showed promising positioning which can be improved by selecting a better-quality LNB.
StarLink (Aventis CropScience US) hybrid corn has been genetically modified to contain a pesticidal protein, Cry9C, which makes it more resistant than traditional varieties to certain types of corn insect pests. Unlike other varieties of genetically engineered corn, the U.S. Environmental Protection Agency authorized the use of StarLink corn for animal feed and industrial use only, not for human consumption. However, some Cry9C-containing corn was mistakenly or inadvertently comingled with yellow corn intended for human food use. Because corn containing the Cry9C construct was not approved for human use, the U.S. Food and Drug Administration considers food containing it to be adulterated. Consequently, this regulatory violation resulted in hundreds of recalls of corn-based products, such as taco shells, containing cry9C DNA. Detecting the novel protein in StarLink corn is an emerging issue; therefore, there is no standardized or established analytical method for detecting Cry9C protein in processed foods. We developed a procedure for quantitation of Cry9C protein, with validation data, in processed food matrixes with a limit of quantitation at 1.7 ng/g (ppb), using a commercial polyclonal antibody-based Cry9C kit that was intended for corn grain samples. Intra- and interassay coefficients of variation were 2.8 and 11.8%, respectively. Mean recoveries were 73 and 85% at 2 and 5 ng/g Cry9C fortifications, respectively, for 19 control non-StarLink corn-based matrixes. Our data demonstrate only 0-0.5% of Cry9C protein survived the processing of tortilla chips and soft tortillas made from 100% StarLink corn, resulting in levels from below the detection limit to 45 ppb.
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Modern biotechnology has dramatically increased our ability to alter the agronomic traits of plants. Among the novel traits that biotechnology has made available, an important group includes Bacillus thuringiensis-derived insect resistance. This technology has been applied to potatoes, cotton, and corn. Benefits of Bt crops, and biotechnology generally, can be realized only if risks are assessed and managed properly. The case of Starlink corn, a plant modified with a gene that encodes the Bt protein Cry9c, was a severe test of U.S. regulatory agencies. The U.S. Environmental Protection Agency had restricted its use to animal feed due to concern about the potential for allergenicity. However, Starlink corn was later found throughout the human food supply, resulting in food recalls by the Food and Drug Administration and significant disruption of the food supply. Here we examine the regulatory history of Starlink, the assessment framework employed by the U.S. government, assumptions and information gaps, and the key elements of government efforts to manage the product. We explore the impacts on regulations, science, and society and conclude that only significant advances in our understanding of food allergies and improvements in monitoring and enforcement will avoid similar events in the future. Specifically, we need to develop a stronger fundamental basis for predicting allergic sensitization and reactions if novel proteins are to be introduced in this fashion. Mechanisms are needed to assure that worker and community aeroallergen risks are considered. Requirements are needed for the development of valid assays so that enforcement and post market surveillance activities can be conducted.
This study examined the influence of transgenic event CBH (StarLink; SL)-derived hybrid corn on growth, health and physiological functions of pigs, as well as the possibility of transferring the cry9C gene or Cry9C protein to the blood, liver or muscles, in comparison with pigs fed a diet with non-transgenic (isogenic) corn (non-SL). The diet for the SL group was composed of 70% SL corn, and the diet for the non-SL group was composed of 70% non-SL corn. Forty pigs approximately 3 months in age were used in the current experiment. After the pigs were acclimatized to their environment for 7 days, they were fed piglet diets for 7 weeks, and afterwards fed growing-finishing diets until the end of the experiment. There were no significant differences in bodyweight gain, feed intake or feed conversion ratio between the pigs fed SL diet and those of non-SL diet. No abnormalities were observed in the health conditions of either the SL or the non-SL group. Moreover, no significant differences were observed between the two groups in hematological values, histopathological examination and necropsy findings. Although the serum biochemical values within each group were normal, the blood urea nitrogen values of the SL group showed a tendency to be slightly higher than those of the non-SL group. Also, the blood glucose values of the SL group were significantly lower than those of the non-SL group. However, the cause of the significant differences in the blood glucose values between the two groups is unknown. The PCR and ELISA did not detect the cry9C gene and Cry9C protein in the blood, liver or muscles of the pigs at the end of the experiment.
In developing countries, satellite-based technology can aid critical telemedicine applications and other digital health services in critically underserved areas. Affordable, high-speed broadband services can and should be accessible to all citizens. Remote locations are necessary to support various critical services, including education and training, telehealth applications, remote patient monitoring, and warning systems, particularly during disasters. Currently, however, these services are limited to urban centers, leaving rural areas without access to specialized health care services. This digital divide significantly impacts health care delivery, with only 48% of rural populations having internet access compared with 83% in urban areas. The goal of this study was to assess the suitability of Geostationary Earth Orbit (GEO), Medium Earth Orbit (MEO), and Low Earth Orbit (LEO) satellites for telemedicine and health care backhaul connectivity. To achieve this, the study conducted a comparative analysis of the systems, highlighting their respective advantages and limitations in terms of latency, coverage, and deployment costs. A systematic literature review and the assessment of real-world case studies and worldwide datasets complemented this analysis. Case studies from Starlink deployments in North America and Sub-Saharan Africa and Amazon's Project Kuiper were evaluated. LEO satellites demonstrated significantly lower latency (20-50 ms) compared with MEO (100-300 ms) and GEO (600 ms) systems. Cost analysis revealed LEO services ($110-$500 per month) were substantially more affordable than MEO ($250-$1,000 per month) and GEO ($500-$2,000 per month) alternatives. Starlink deployments achieved download speeds of 50-250 Mbps with sub-50 ms latency, enabling real-time telemedicine consultations that met clinical standards. Rural telemedicine consultations increased by over 300% in areas with LEO satellite coverage. Our findings suggest that the LEO Starlink satellite technology would provide the most cost-effective backhaul broadband connectivity for real-time telemedicine services, given its low latency needs (20-50 ms), which enable high-quality video calls and remote diagnostics. We recommend using an LEO-based satellite network as the best approach to extend internet services to underserved remote communities due to its low latency and cost-effectiveness in aiding health care delivery in developing countries.
This study describes exploratory, in-situ experimentation to measure Very Low Frequency (VLF) plasma waves (1-35 kHz) at times when a space physics satellite equipped with a radio plasma wave receiver conjuncts with other space objects. The objective was to learn if a secondary space object's rapid passage near another satellite is detectable. If so, this would offer a new avenue to infer the presence of space debris in Earth orbit. Space objects in Earth's ionosphere develop a region of ion density rarefactions in the wake of their orbital motion which could serve as the basis for object detection. In 2022 the Canadian space physics satellite CASSIOPE used its radio plasma physics package during conjunctions with other satellites and recorded ambient electric field data at times prior to, during and after the time of closest approach of CASSIOPE and the secondary object. CASSIOPE is designed to measure Earth's aurora, particles, fields and has an eccentric 330 × 1200 km orbit which fortuitously samples a variety of plasma regimes in Earth's ionosphere to test this approach. This orbit regularly crosses the altitudes of highly populated orbital shells such as Starlink, Iridium and OneWeb offering regular conjunction opportunities to attempt measurement of plasma oscillations. CASSIOPE collected electric field measurements using its crossed-dipole Radio Receiver Instrument (RRI) which detects plasma electric field oscillations. CASSIOPE sampled 35 conjunctions using the RRI from 4 March to 10 June 2022. It was surmised that if CASSIOPE traversed an ion density rarefaction the RRI should produce broadband noise at times correlating with the time of closest approach. Of the 35 conjunctions sampled, 3 exhibited VLF broadband noise somewhat correlated to the time of closest approach but were difficult to differentiate from background ambient auroral activity. One conjunction showed strong temporal correlation where a conjuncting Starlink appears to have threaded the magnetic field line between itself and CASSIOPE which also traversed the Starlink's wake. All other conjunctions where the secondary object passed behind CASSIOPE or were quite distant (~ 5-10 km) from CASSIOPE did not show wave power exceeding the ambient background. The CASSIOPE findings indicate that sensing of ion density rarefactions in space object wakes does not appear practical to implement and clear, repeatable signatures from known space object conjunctions were not identified during this investigation.
This article examines how Starlink, developed by SpaceX, constitutes a disruptive innovation in the telecommunications sector in Cameroon, where it offers connectivity in areas poorly served by traditional networks. However, there is a tension between the ideal and the market realities of democratizing internet access. On one hand, like philanthrocapitalist initiatives, Starlink promotes itself through humanitarian efforts that promise global internet access, presented as a public good. On the other hand, its business strategies privatize access and make it unaffordable for a large portion of the global population. Starlink is reshaping geopolitical and economic relations not only by competing with national operators and challenging regulatory agencies, but also by cooperating with local telecom actors and, in some cases, relying on their infrastructure to ensure the continuity of its services. Its success is further supported by a widespread crisis of user mistrust in traditional telecommunications infrastructures, fueled by frequent outages and high costs, positioning Starlink as a trust infrastructure. Our analysis shows that, while Starlink claims to promote digital inclusion, its market-driven logic deepens existing inequalities-amplifying what has long been a major challenge of internet access and rendering it even more visible and politically salient in the 21st century.
With human activities in outer space becoming increasingly frequent, including the construction of space stations and satellite constellations such as Starlink, OneWeb, and G60 Qianfan Constellation, the protection of spacecraft against atomic oxygen (AO) in the low-Earth orbit (LEO) has become critical. AO, characterized by its strong oxidative capability and high collisional energy, has been considered the most serious hazard to the LEO spacecraft. Recently, it was found that scale-like Mg-Al layered double hydroxide (LDH) coatings are highly effective in protecting flexible spacecraft parts from AO erosion. However, the AO protection mechanism of the scale-like coatings remains unclear, which limited the further development of this AO protection technology. The erosion process of AO takes place at the atomic scale and on the femtosecond time scale, making it difficult to reveal the microscopic mechanism solely by experimental and characterization studies. To address this, we investigated the interactions between AO and the coating materials using first-principles based calculations and simulations. By simulating the AO impact and calculating the AO adsorption energy on polysiloxane and LDH nanosheets, a possible AO protection mechanism was proposed using experimental and characterization studies. With the special scale-like structure, the coating mainly inhibits the AO erosion through the barrier effect on the coating surface and the obstruction effect inside coatings with long erosion paths. This work shows that the non-dense micro-nanostructure holds potential for AO protection, which will guide and expand the application of assembled nanomaterials in space exploration.
The deployment of low Earth orbit (LEO) satellite mega-constellations enables global broadband access, but their high orbital velocity demands frequent handover decisions that critically impact service continuity. Conventional strategies that maximize instantaneous signal quality often trigger excessive handovers, while stability-focused approaches may sacrifice link performance. In this paper, we propose the Hybrid Handover Strategy (HHS), a low-complexity algorithm that addresses this trade-off. The HHS utilizes a multi-attribute utility function that integrates the signal-to-interference-plus-noise ratio (SINR), satellite elevation angle, and network load with a novel logistic-decay stability bonus mechanism. We provide a formal mathematical analysis of the algorithm's stability and performance trade-offs. To ensure industrial relevance, the strategy is validated using a high-fidelity simulator driven by real-world two-line element (TLE) data from the Starlink constellation. Results demonstrate that the HHS reduces the handover frequency by 64% compared to SINR-based benchmarks while maintaining service availability of 90.2%. The proposed algorithm delivers these improvements with significantly smaller computational overhead than machine learning approaches, making it suitable for resource-constrained on-board processing and ground terminals.
Polycrisis (intersections of multiple, compounding crises) fracture health communication. Despite rising frequency in Southeast Asia, empirical evidence on how health information is adapted and diffused is scarce. Myanmar's 2025 earthquake, amid armed conflict and internet shutdowns, offered a critical case. Participatory mind-mapping was conducted with 24 stakeholders, including humanitarian and health workers, media actors, and community leaders, representing a diverse range of experts and implementors involved in the crisis response. In each session, participants mapped how health information flowed across actors, channels, and barriers. Reflexive thematic analysis of maps, transcripts, and notes identified diffusion pathways and adaptive strategies. Diffusion spanned assessment, planning, and delivery but was seldom linear. Actors shifted among messaging apps, satellite links, radio, and in-person relay as connectivity, censorship, and security changed. Credibility increased when messages were community-verified, paired with aid, and localized to resource constraints (e.g., substituting supplies assumed available in global protocols with local alternatives). Communities organized their own coordination arrangements, such as household ledgers, that sometimes outperformed formalized systems. Digital innovations shaped operations: Starlink restored connectivity during blackouts; Virtual Private Networks (VPNs) and platform switching (Telegram, Viber) bypassed censorship; and verification networks sought to counter misinformation. Reliance on digital channels alone was inadequate given limited literacy, surveillance, and displacement; radio, printed flyers, and religious or community gatherings remained essential for many groups. In Myanmar's polycrisis context, and potentially in comparable settings, findings suggest resilient diffusion may benefit from hybrid approaches combining new connectivity tools (satellite internet, VPNs, mesh networks) with trusted offline and community-led practices, attending to equity, safety, and appropriateness.
The Pacific Islands face formidable barriers to timely neurosurgical care, driven by geography, limited resources, and fragile referral systems. Fiji functions as a regional hub but remains constrained by centralization, distance, and workforce limitations. To synthesize available evidence on neurosurgical access, aeromedical retrieval, and telehealth across Fiji and neighboring island states, identifying gaps and opportunities for system strengthening. A structured narrative review was conducted following the Standards for Narrative Reviews (SANRA) guidelines. Searches were performed in PubMed, Scopus, and Google Scholar for English-language publications from January 2000 to July 2025 using predefined keywords and Boolean combinations ("Fiji" OR "Pacific Islands") AND ("neurosurgery" OR "neurotrauma" OR "traumatic brain injury" OR "stroke") AND ("telemedicine" OR "aeromedical retrieval" OR "air evacuation" OR "global surgery"). Reference lists were hand-searched, and gray literature from the World Health Organization (WHO) and Pacific Ministries of Health was included. A total of 164 records were identified and 42 retained for qualitative synthesis (29 peer-reviewed and 13 Gray literature sources). Records were grouped thematically according to Global Surgery 2030 (GS2030) benchmarks. Fiji reports high incidence of traumatic brain injury and stroke with substantial pre-hospital mortality. Neurosurgical services are centralized in Suva, Lautoka, and Labasa, leaving outer islands dependent on costly, weather-sensitive aeromedical retrieval. Early telehealth pilots demonstrated feasibility but lacked sustainability. The 2024 rollout of satellite internet (Starlink) offers new potential for real-time imaging transfer, remote consultation, and coordinated retrieval activation, though evidence from prospective pilots remains limited. Fiji's emerging role as a regional stabilization and tele-neurosurgery hub highlights a feasible model for strengthening neurosurgical access across the Pacific. A tiered network linking national hospitals to tertiary centers in Australia, New Zealand, India and France could reduce inequity if supported by regional policy frameworks, workforce upskilling, and outcome monitoring.
With the maturation of reusable launch vehicle technology and satellite mass-production capabilities, global mega-constellation projects have entered a phase of rapid expansion. Inter-satellite networking is a key approach for enhancing constellation performance, as it crucially impacts overall constellation effectiveness. However, existing studies mostly focus on the network layer protocol optimization, with insufficient attention to topological structure design, and fail to fully consider the engineering challenges associated with inter-orbit Inter-Satellite Links (ISLs). To address these issues, this paper proposes a heterogeneous ISL topology architecture for mega-constellations, centered on "stable high-speed laser backbone connection within intra-orbit planes + dynamic and flexible radio network between inter-orbit planes". First, we clarify the optimization objectives for mega-constellation topological design under this architecture and theoretically prove that the optimization problem is NP-hard. Building on this, we introduce Topological Structure Units (TSUs) and employ a unit reuse strategy to simplify topological design. Furthermore, we propose a TSU-based heterogeneous ISL topological design algorithm. Considering the uneven satellite distribution across latitude zones within the constellation, we further propose a regional TSU-based topological design algorithm. Finally, through simulation experiments in Starlink and GW constellation scenarios, we conduct multi-dimensional verification to demonstrate the effectiveness of the proposed algorithms in reducing end-to-end delay and decreasing ISL hops.
This paper delves into an interference analysis, focusing on the forthcoming Starlink Generation 2 satellites, stated to operate within the 1990-1995 MHz frequency band. The aim is to assess the potential interference from this Starlink system to the satellite receivers of mobile satellite systems (MSSs), which are set to function within the 1980-2010 MHz range, and satellite receivers of the NTN systems, which are planned to operate in the n256 bands, defined by the 3GPP specifications. Through simulation-based evaluations, both single-entry and aggregate interference levels from Starlink to MSSs and NTN systems are comprehensively explored. To estimate the interference impact, several protection criteria were used. The study is in line with the Recommendations of International Telecommunication Union (ITU-R) and common approaches that are used when performing compatibility studies between satellite systems. The findings of this study demonstrate the feasibility of utilizing the n25 band for NTN direct-to-device services.
This article present the design of a broadband filter structure spanning the S, C, X, and Ku uplink bands based on a novel coupling signal path generation. The core design features a centrally symmetric serial via hole array, microstrip line, and curved coplanar waveguide. This structure offers advantages such as low loss band pass, low frequency stopband in the S band, and stable transmission zeros while providing a broadband passband. Additionally, to address the signal suppression requirements in commercial communication frequencies, such as 5G base stations, 6G IMT, satellite TV, and Starlink, across the S, C, X, and Ku uplink bands, a dual-band notch structure for the C band and three improved signal suppression structures are proposed. Finally, the design achieves miniaturization and integration while ensuring excellent performance across all five independent stopbands. Experimental results closely match simulation findings: the filter exhibits a -3 dB bandwidth of 2.4-14.3 GHz with a relative bandwidth of up to 141%. Each of the five suppression depths reaches -15 dB, occupying a compact footprint of only 14×10.8mm2,with a relative wave guide area of 0.38 × 0.29λ2.
Over the past six decades, astronomy, space science, and the space industry have seemed to be in a kind of virtuous symbiosis. Astronomy has benefited from improvements in technology and has had the opportunity to place observing platforms in space. The space industry has been pushed by the extreme technological demands of curiosity-driven research, and benefited from the flow of public money to industrial contracts to build astronomical missions. Both science and industry have been driven by a shared romantic vision of exploring the Universe, whether by studying distant galaxies or by humanity stepping out into space. All of this was suddenly disrupted in 2019 by a rude awakening. Starlink communication satellites began to photo-bomb astronomers' images as they streaked across the sky. Suddenly, it seemed, astronomy and commercial space activity were in conflict. This friction may be coming to a crunch as the Vera C. Rubin Observatory begins a 10-year survey of the cosmos.