Source: GAO
Introduction
Sputnik, the first artificial satellite in space, launched in 1957. The number of active satellites increased steadily for the next 50 years, then surged from around 1,400 in 2015 to almost 5,500 by spring of 2022.1 This trend is expected to accelerate, with multiple experts mentioning around 58,000 additional satellites could be launched by the end of the decade, over 10 times the current number of active satellites. One reason for this acceleration is the ongoing and proposed launches of a series of large constellations of satellites, which private companies plan to use to provide important services, such as broadband internet access in underserved rural communities.
Satellites can have a number of environmental and other effects, especially as the number of satellites in orbit continues to increase. For example, emissions from the rockets that carry satellites into space could cause a change in the temperature of the upper atmosphere. The increasing numbers of satellites could create additional orbital debris, which complicates satellite operations. Sunlight reflections and radio transmissions from satellites could disrupt telescopes, which could make it more difficult for astronomers to assess risks associated with near-Earth asteroids or to observe other celestial objects.
Furthermore, the projected number of future satellites as well as some of the potential environmental and other effects still have considerable uncertainties, which we note throughout this report. Despite these uncertainties, we report projected numbers of satellites and their potential effects and their associated uncertainties, where available, to provide a descriptive account of the emergence of large constellations of satellites and what effects they might have.
In light of the broad congressional interest in commercial satellites, we prepared this technology assessment under the authority of the Comptroller General of the United States to assist Congress with its oversight responsibilities. This report: (1) describes the potential effects from projected increases in large constellations of satellites, (2) assesses the current or emerging technologies and approaches to evaluate and mitigate these effects, along with challenges to developing or implementing these technologies and approaches, and (3) identifies policy options that might help address the challenges as well as the opportunities and considerations that accompany these options.
We focused this technology assessment on large commercial constellations of satellites, considering direct environmental and other effects that the constellations may introduce or exacerbate. We reviewed literature; interviewed agency officials, industry representatives, and experts in academia and at a federally funded research and development center; and conducted a meeting of experts. The meeting included a nongeneralizable group of 15 experts-selected based on their technical, legal, economic, or policy expertise-that would represent a balanced and diverse set of views from government scientists, nongovernmental experts, industry representatives, and academic researchers. For more information on the objectives, scope, and methodology of this technology assessment, see Appendix I.
We conducted this technology assessment from April 2021 to September 2022 in accordance with all sections of GAO’s Quality Assurance Framework that are relevant to technology assessments. The framework requires that we plan and perform the engagement to obtain sufficient and appropriate evidence meet our stated objectives and to discuss any limitations to our work. We believe that the information and data obtained, and the analysis conducted, provide a reasonable basis for any findings and conclusions in this product.
