Impacts of Large Satellite Constellations on Astronomy: Live Updates
Kelsie Krafton American Astronomical Society (AAS)
If you have questions about the impact of satellite constellations on astronomy, AAS's Public Policy Department (AASPPD) will be publishing updates on this page from now on. Many of our efforts are done in collaboration with the IAU as part of an AAS/IAU Satellite Constellation Working Group (SCWG).
Updates from the AAS
- The SATCON2 Workshop is announced and accepting applications to join the working groups.
- AASPD and the International Astronomical Union's U.S. National Committee (USNC/IAU) wrote a letter to the U.S. Department of State urging them to endorse the Dark and Quiet Skies Conference Room Paper (CRP) moving forward at the April United Nations (U.N.) sub-committee meeting. SCWG members presented on satellite constellations to the National Academies' Board on Physics and Astronomy (NAS BPA). AASPPD discussed options for authorizing NSF to address satellite constellations with Congressional staffers.
- AASPD wrote a reply to the Visasat FCC comment on a Starlink filing, thanking Viasat for calling attention to the impacts of satellite constellations on astronomy and correcting some mistakes in their filing. The SCWG hosted a special session at the AAS 237 winter meeting on "Astronomy and Satellite Constellations" with a panel that included astronomers, SpaceX, OneWeb and Amazon. AASPPD reached out to engineering societies to collaborate on awareness raising.
- The AASPPD wrote letters to the incoming Biden-Harris transition team, and included a section on the need to preserve our dark and quiet skies. Members of the SCWG present at the ASP meeting on satellite constellations.
- Members of the SCWG contributed to a Nature Astronomy paper on satellite constellations which was published on 6 November as part of a special edition on small satellites (see publications for more articles). AASPPD met with the Biden transition team member for the NSF and raised the issue of the threat to ground based observing posed by satellite constellations.
- The SCWG participated in the Dark and Quiet Skies Workshop. The workshop was divided into Working Groups on the sub-disciplines of optical astronomy, radio astronomy, dark sky places, light effects on the bio-environment, and the impact of satellite constellations on astronomy, both radio and optical. The AASPPD joined the Recommendations group within the Satellite Constellation Working Group. Astronomers, operators, and space lawyers worked together to draft recommendations toward international policy using the results in the report produced from the (June 28 - July 2) Satellite Constellation (SATCON1) Workshop. The AASPPD set up the SCWG's first meeting with the FCC to discuss the SATCON1 Report recommendations. The AAS and SIA teamed up again to do a 1-hour informational webinar for the satellite industry on astronomer's concerns about satellite constellations. The focus this time was going over the technical recommendations of the SATCON1 Report.
- The SATCON1 Report was published on the bulletin of the American Astronomical Society. The SCWG had their first meeting with SpaceX since the report came out to discuss observations of VisorSat. The interagency Astronomy and Astrophysics Advisory Committee (AAAC) met this month and discussed the report. Tony Tyson and Joel Parriott co-authored a piece for Science magazine, "Dark Skies and Bright Satellites".
- The AAS press briefing on the SATCON1 report was held on August 25. The report has been publicly available since that event. NOIRLab released a simultaneous announcement of the report. The AASPPD launched a follow-up advocacy campaign to get the word out about the report. On 31 August we had a briefing with Hill staff.
- The SCWG, as members of the SOC, hosted a technical workshop from 29 June to 2 July. The goal of this workshop is to produce a white paper, which the working groups have been working on assembling throughout July. The white paper should become available during the month of August. The AASPPD advocated to get the issue of satellite constellations included in the NSF authorization.
- Members of the SCWG presented at AAS 236 during a press conference and a plenary session. If you registered for AAS 236, you can use your login to watch sessions posted on our site, and in about six months they will be made available to the public (around the time of AAS 237). Members of the SCWG presented to the National Academy of Sciences (NAS) Space Studies Board (SSB) and Aeronautics and Space Engineering Board (ASEB) at the 2020 Joint Meeting of the ASEB and the SSB, held virtually this year 8-11 June. The SCWG is organized a technical workshop for 29 June to 2 July. Also NSF's Spectrum Innovation Initiative: National Center for Wireless Spectrum Research (SII-Center) has issued a call for proposals due June 12. There was also the Astro2020 meeting on radio frequency interference.
- AASPPD establishes this webpage to help keep the community better informed. AASPPD co-hosted a webinar with the Satellite Industry Association (SIA) aimed at informing the satellite industry of the impacts satellite constellations have on the astronomical sciences.
- The Editor of AAS Nova, Susanna Kohler, published a summary of Jonathan McDowell's ApJL paper on satellite constellations. AASPPD has a call with the International Dark-Sky Association (IDA) to discuss our approach to the satellite constellation problem. Members of SCWG and SpaceX present to the Astro2020 Subcommittee on Satellite MegaConstellations.
- The AASPPD has an informational meeting with the FAA to be more educated on some of the technical aspects of satellite constellations. The AASPPD co-hosted an informational Hill briefing on satellite constellations with our Hill briefing series partner, Smithsonian.
- The AASPPD is contacted by lawyers and the NRDC to discuss satellite constellations and environmental law.
- At AAS 235, AASPPD had an in-person meeting with the Committee on Astronomy and Public Policy during which we discussed our strategy for addressing the impacts of satellite constellations. Also at AAS 235, there was a press conference with members of the SCWG titled "Astronomy Confronts Satellite Constellations", the recording of which is posted under Archived Presentations. Additionally, members of the SCWG and Patricia Cooper of SpaceX sat on a panel for a special session titled "Challenges to Astronomy from Satellites". Then NSF Director, France Cordova, brought up the impacts of constellation satellites on astronomy during a Congressional hearing. AASPPD meets with the Office of Space Commerce to discuss the impacts of satellite constellations on astronomy. The SCWG has our first meeting with OneWeb. Pat Seitzer (MSU, member of SCWG) presents on to the Astronomy and Astrophysics Advisory Committee.
- The SCWG opens a survey for individual observatories to tell us how satellite constellations will impact them, the summary of our findings is here. An update for the community is posted to the AAS Public Policy Blog. Eighth call between SCWG and SpaceX.
- The APPD updates Congressional staffers on satellite constellations.
- The SCWG hosts a call with ground-based OIR observatory directors to discuss impacts from satellite constellations. AASPPD discusses increasing concerns around satellite constellations with Congressional staffers. The AAS Light Pollution, Radio Interference, and Space Debris (LPRISD) Committee invited abstracts for the Special Session "Challenges to Astronomy from Satellites" (formerly "Threats to Astronomy from Lighting and Satellites") which was held on 8 January 2020 at the 235th AAS meeting in Honolulu. The Pentagon laid out a five-year draft budget for the Space Development Agency (SDA), which included plans for fiscal years (FY) 2021 to 2025 for research, development, prototyping, testing and deployment of large constellations of satellites for military use. Virgin Space and Firefly Aerospace give a Congressional briefing on the small satellites launch industry.
- Sixth call between SCWG and SpaceX. ExoAnalytic Solutions gives a Congressional briefing on space debris.
- AASPPD discusses satellite constellations with the National Space Council and the Office of Science and Technology Policy.
Updates from Others
- Rep. Mike Levin (D-Calif.) appealed to acting FCC Chair Jessica Rosenworcel to address the threat orbital debris poses to spacecraft, the environment, and safety on Earth by regulating satellite constellations and studying their cumulative impact on the environment. The FCC approved the lowering of Starlink orbits to 550 km (from 1150 km). You can read the ruling here. There is a detailed description of the effects on astronomy in Section 4 “Potential Impact on the Night Sky and Astronomy” (pages 47-50). The FCC referenced AAS’s statement and the SATCON1 report in their ruling. Acknowledgment of our input in their deliberations is a big step forward. Even more notable is the following line of text: " ... we conclude that it nonetheless would serve the public interest under the Communications Act for SpaceX to ensure that it does not unduly
burden astronomy and other research endeavors … ” This sets a precedent for all future arguments made before the FCC that impacts to astronomical observations be considered in rulings.
- NASA and SpaceX signed a joint agreement to share information to improve space safety. The American National Standards Institute (ANSI) has released a report of its December informational meeting, "Standardization and the Commercial Space Industry – Space Situational and Domain Awareness, Space Traffic Coordination and Management, and Orbital Debris Mitigation".
- Viasat responds on February 4 to the letter filed by SpaceX on the petition that Viasat filed on December 22, 2020. A meeting on Space as a Global Commons had a heavy focus on satellite constellations and the exploitation of the Moon.
The German Astronomical Society (AG), the German association of amateur astronomers (VdS) and the Society of German-Speaking Planetariums (GDP) issue a statement on the rapid increase in the number of satellites in the night sky. The United Nations's Office of Outer Space Affairs (UNOOSA) and the International Astronomical Union (IAU) published the Report and Recommendations of the online workshop "Dark and Quiet Skies for Science and Society".
- NASA and the UN sign a memorandum of understanding on peaceful uses of space. Viasat appealed to the FCC to review SpaceX’s plans to reposition to a lower orbit some 3,000 satellites from its Starlink constellation, citing the National Environmental Policy Act.
NASA filed an objection at the FCC to the April 2020 petition by US satellite operator AST&Science for a US operating license for its 243-member LEO constellation at 720 km orbital altitude. The April 2020 technical schedule from AST&Science lists the terrestrial mobile frequency bands in which it intends to transmit space-earth below 2 GHz and mis-attributes them to the mobile-satellite service. AST&Science subsequently explained in its October 2020 amended petition and 2 GHz downlink analysis that AST&Science would not operate in the terrestrial mobile spectrum bands when its satellites transmit in the terrestrial mobile spectrum bands below 2 GHz because AST&Science would lease spectrum rights belonging to a willing terrestrial mobile service operator. According to T-Mobile, AST&Science must operate under mobile service rules if it leases spectrum rights to mobile service spectrum from a mobile service operator. AST&Science has registered its constellation through the administration of Papua New Guinea, so the launch is already registered at ITU-R and is not waiting for the FCC. AST&Sciences operations threaten radio astronomy by rendering our terrestrial quiet and coordination zones useless. A Hubble image is photobombed by Starlink.
- The Square Kilometre Array (SKA) issued a statement on satellite constellations. The Aerospace Corporation will publish papers on NASA’s Artemis program, the space workforce, space deterrence, space doctrine and light pollution from satellites on Oct. 28.
- The Center for Space Policy and Strategy published "Space Traffic Management: The Challenge of Large Constellations, Orbital Debris, and the Rapid Changes in Space Operations"
- OneWeb announces it is filing for up to 48,000 satellites with the FCC. A batch of FCC filings for OneWeb, Mangata, and ViaSat.
- FCC Fact Sheet for Mitigation of Orbital Debris in the New Space Age and an article from the Professional Aerospace Contractors Association on challenges to the FCC's new orbital debris regulations. SpaceX files with the FCC to lower the Starlink orbits. SpaceX itself also issued its own statement and there is a summary with additional context on the AAS website.
- A press release from ESO and AIP FYI's weekly update for for the week of 9 March 2020 covered the AASPPD Hill briefing on satellite constellations.
- A report by the Institut Montaigne (a French think tank) recommends the European Union write policy governing broadband satellite constellations.The IAU issued a press release "Understanding the Impact of Satellite Constellations on Astronomy".
- ESO makes a statement on satellite constellations
- OneWeb submits a letter to the FCC in opposition of SpaceX's applications to expand their Starlink constellation. One week later SpaceX submitted its own letter to the FCC.
- Amazon's Kuiper satellite constellation submits a letter to the FCC
- SpaceX FCC filing for Starlink
- Gaspar Bakos (Princeton) also keeps an updates page for satellite constellations.
- Jonathan McDowell (CfA) also keeps an update page for satellites and launches (twitter)
- Olivier Hainaut's simulations page
- "Report on Mega-Constellations to the Government of Canada and the Canadian Space Agency" by Boley et al. Submitted to CSA on March 31 2021.
- "Study finds nowhere on Earth is safe from satellite light pollution" by Joshua Sokol. Science. Mar. 2021
- "The proliferation of space objects is a rapidly increasing source of artificial night sky brightness" by M. Kocifaj et al. MNRAS. Mar. 2021
- "The Brightness of VisorSat-Design Starlink Satellites" by Anthony Mallama. arXiv. Jan. 2021
- "The Brightness of OneWeb Satellites" by Anthony Mallama. arXiv. Dec. 2020
- "Simultaneous Multicolor Observations of Starlink's Darksat by the Murikabushi Telescope with MITSuME" by Takashi Horiuchi et al. ApJ. Dec. 2020
- "The impact of satellite constellations on space as an ancestral global commons" by Aparna Venkatesan et al. Nature Astronomy. Nov. 2020
- "The challenge of satellite megaconstellations" by Robert Massey, Sara Lucatello & Piero Benvenuti. Nature Astronomy. Nov. 2020
- "A space science boom or death by a thousand small satellites" editorial for Nature Astronomy. Nov. 2020
- "Dark Skies and Bright Satellites" by Anthony Tyson and Joel Parriott. Science. Sept. 2020
- "Impact of Satellite Constellations on Optical Astronomy and Recommendations Toward Mitigations" by Walker et al. BAAS. Aug. 2020
- "Hopes and Concerns for Astronomy of Satellite Constellations" by Levchenko et al. Nature Astronomy. Jun. 2020
- "Starlink Satellite Brightness Before VisorSat" by Anthony Mallama. arxiv. Jun. 2020
- "The Low Earth Orbit Satellite Population and Impacts of the SpaceX Starlink Constellation" by Jonathan C. McDowell. Ap J Letters. Apr. 2020
- "The Future of the Night Sky: Light Pollution from Satellites" by the Aerospace Corporation. Mar. 2020.
- Report on impact from LEO satellite constellations by Vera C. Rubin Observatory (last update Mar. 2020)
- "On the Impact of Satellite Constellations on Astronomical Observations in the Visible and Infrared Domains" by Olivier R. Hainaut and Andrew P. Williams. Astronomy and Astrophysics. Mar. 2020
- An article in Via Satellite (Apr. 2021) on Northrop Grumman and the future of in-orbit satellite servicing
- An article in Via Satellite (Apr. 2021) on a conversation with Gwynne Shotwell
- An article in Via Satellite (Apr. 2021) on SES details ground station for O3b mPOWER
- An article in Via Satellite (Apr. 2021) on FCC approving SpaceX request to lower Starlink’s altitude
- An article in Via Satellite (Apr. 2021) on OneWeb constellation reaching 182 satellites
- An article in Via Satellite (Apr. 2021) on optical link Japanese Startup Warpspace
- An article in Via Satellite (Apr. 2021) on OQ technology signs constellation launch deal with Spaceflight
- An article in Via Satellite (Apr. 2021) on laying the IT groundwork for a crowded space economy
- An article in Space News (Apr. 2021) on China developing plans for a 13,000-satellite megaconstellation
- An article in Via Satellite (Apr. 2021) on satellite broadband market to reach 5 million subscribers by 2026
- An article in Via Satellite (Apr. 2021) on Amazon signing with ULA for 9 Project Kuiper launches
- An article in Via Satellite (Apr. 2021) on EOSDA’s Max Polyakov sharing LEO agriculture constellation plans
- An article in Via Satellite (Apr. 2021) on how software-defined satellites will shape communications
- An article in Via Satellite (Apr. 2021) on Gilat’s Wavestream receiving $20M in LEO constellation SSPA orders
- An article in Space News (Apr. 2021) on greenhouse gas monitoring constellation Carbon Mapper
- An article in Via Satellite (Apr. 2021) on the top 10 takeaways from SATELLITE 2021’s LEO Digital Forum
- An article in Via Satellite (Apr. 2021) on Lockheed Martin's new line of mid-size ISR satellites
- An article in Via Satellite (Apr. 2021) on Telesat Lightspeed
- An article in Via Satellite (Apr. 2021) on Air Canada banking on LEO technology
- An article in The Verge (Apr. 2021) on OneWeb, SpaceX satellites dodged a potential collision in orbit
- An article in Via Satellite (Apr. 2021) on MDA contracting analog devices for Telesat Lightspeed beam forming tech
- An article in Engadget (Apr. 2021) on entombing the Earth in an impenetrable shell of dead satellites
- An article in The Washington Post (Apr. 2021) on the satellite constellation technology
- An article in Via Satellite (Apr. 2021) on OneWeb CEO Neil Masterson
- An article in Via Satellite (Apr. 2021) on new LEO constellations driving tech changes on the ground
- An article in Via Satellite (Apr. 2021) on Starlink reaching every rural U.S. household in 5 years
- An article in Via Satellite (Apr. 2021) on operators sparring over satellite broadband market size
- An article in Via Satellite (Apr. 2021) on the rise of the Indian satellite market
- An article in The New York Times (Apr. 2021) on a proposed $100 billion fix for the digital divide
- An article in Via Satellite (Apr. 2021) on former NASA Administrator Bridenstine joins Viasat’s board
- An article in Via Satellite (Mar. 2021) on the Hanwha Systems 2,000-Satellite LEO constellation
- An article in Via Satellite (Mar. 2021) on a new LEO satellite constellation
- An article in Via Satellite (Mar. 2021) on a OneWeb
- An article in Via Satellite (Mar. 2021) on a Starlink
- An article in Via Satellite (Mar. 2021) on a new constellation
- An article in Via Satellite (Mar. 2021) on OneWeb launches
- An article in Space News (Feb. 2021) on the Telesat constellation
- An article in Space Newsfeed (Feb. 2021) on a new constellation to measure nighttime light on Earth
- An article in Sky & Telescope (Jan. 2021) on the brightness of satellite constellations
- An article in Sky & Telescope (Jan. 2021) on the future of satellite constellations
- An article in Space News (Jan. 2021) on the smaller size of OneWeb
- An article in Physics World (Jan. 2021) on dark-coated Starlink satellites
- An article in Space News (Dec. 2020) on Viasat asking the FCC to perform environmental review of Starlink
- An article in Forbes (Dec. 2020) on Hubble's image of the year, one of which was photobombed by Starlink
- An article in Space News (Dec. 2020) on pollutants produced during satellite and rocket reentry
- An article in Via Satellite (Dec. 2020) on Mynaric and laser terminals on megaconstellations for data is transfer in space
- An article from The Conversation (Nov. 2020) on Starlink
- An article in ars technica (Nov. 2020) on NASA's objection to a new megaconstellation
- An article in the Independent (Oct. 2020) on SpaceX
- An article in Quartz (Oct. 2020) on Starlink
- An article in ars technica (Oct. 2020) on Starlink
- An article in Buisness Insider (Oct. 2020) on Starlink
- An article in Air & Space Magazine (Oct. 2020) on Starlink
- An article in The Verge (Sep. 2020) on Starlink
- An article by AIP's FYI (Sep. 2020) on the SATCON1 Report
- An article in Nature (Aug. 2020) on the SATCON1 Report
- An article in EarthSky (Aug. 2020) on the SATCON1 Report
- An article in ars technica (Aug. 2020) on OneWeb's FCC approval for another 1,280 satellites
- An article in Via Satellite (Aug. 2020) on FCC approval of OneWeb's 2,000-Satellite Constellation
- An article from Space News (Aug. 2020) on the SATCON1 Report
- An article from Science (Aug. 2020) on the SATCON1 Report
- An article from the New York Times (Aug. 2020) on Amazon's Kuiper constellation
- An article from Via Satellite (Jul. 2020) on FCC approval for Amazon's Kuiper constellation
- An article from Space News (Jul. 2020) on FCC approval for Amazon's Kuiper constellation
- An article from Via Satellite (Jul. 2020) recapping a LEO constellation webcast
- An article from Discover Magazine (Jul. 2020) on NASA's satellite tracking citizen science program
- An article from ENewsPlanet (Jul. 2020) on the Starlink photobomb of comet Neowise
- An article from GeekWire (Jul. 2020) on the FCC's approval of the Kuiper constellation
- An article from Forbes (Jul. 2020) on the UK saving OneWeb
- An article from The Telegraph (Jun. 2020) on the UK saving OneWeb
- An article from Bloomberg Law (Jun. 2020) on the conflict between dish and satellite services
- An article form Space News (Jun. 2020) on FCC evaluation of LEO constellations
- An article from Space News (Jun. 2020) on the presentations at AAS 236
- An article on LinkedIn (May 2020) on a new FCC processing round
- An article from Space News (May 2020) on another satellite constellation
- List of articles from GeekWire on Amazon's Project Kuiper
- An article from GeekWire (May 2020) on Amazon's interest in acquiring OneWeb
- An article from SpaceRef (May 2020) on OneWeb's increase to 48,000 satellites
- An article from Room (Apr. 2020) on ground-based observing
- An article from Space Daily (Apr. 2020) on the Starlink sunshades
- An article from PetaPixel (Apr. 2020) on SpaceX's mitigation plan
- An article from Space News (Apr. 2020) on a new rules proposal for the FCC
- An article from The Telegraph (Apr. 2020) on OneWeb's bankruptcy
- An article from Sky & Telescope (Apr. 2020) on Starlink and astronomy
- An article from SpaceNews (Mar. 2020) on a new megaconstellation startup
- An article from The Space Review (Mar. 2020) on OneWeb and Starlink
- An article from Business Insider (Mar. 2020) on a meeting between European astronomers and SpaceX
- An article from Politico (Mar. 2020) on Astranis, a new type of satellite constellation
- An article from cnet (Mar. 2020) on Elon Musk's comments on Starlink at the SATELLITE2020 conference
- An article from Newsweek (Feb. 2020) on Russian complaints about satellite constellations
- An article from Bloomberg news (Feb. 2020) on SpaceX considering a public offering of Starlink
- An article from BBC News (Jan. 2020) on Starlink's time constraints to fix the brightness issue
- An article from Scientific American (Jan. 2020) on whether satellite constellations violate environmental law
- An article from SpaceNews (Jan. 2020) on SpaceX's launch schedule for 2020
- An article from SpaceNews (Dec. 2019) on changes to the Starlink satellite constellation
- An article from SpaceNews (Dec. 2019) on the downsizing of the Sky and Space Global constellation
- An article from SpaceNews (Nov. 2019) on the shutdown of LeoSat
- An article from The New York Times (Nov. 2019) on the negative impacts to astronomy from satellite constellations
- An article from SpaceNews (Sept. 2019) on whether satellite constellations can be responsible users of space
- An article from SpaceNews (May 2019) on the development of a "space sustainability" rating system
Social Media Updates
- Verse posted a video on satellite constellations
- Latest simulation of planned satellite constellations
May: The 6th round of the East African Astronomical Society Workshop (EAASW) 20-22 May 2021 is having a session on Astro-Tourism, Dark Sky and Cultural Astronomy and Heritage
June: The Town Hall "Astro2020 Advocacy, Satellite Constellations, and More!" will take place on 9 June 2021 at AAS 238.
July: The Special Session SS31 “Impact of Satellite Constellations on Astronomical Activities” will take place on 2 July 2021 as part of the European Astronomical Society Annual EAS2021, hosted virtually by Leiden observatory between 28 June 28 and 2 July 2021. The SATCON2 Workshop will be 12-16 July 2021.
Participate in a long-term citizen science project to photographically track the population growth of satellites constellations over time.
You can also post observations here.
- Aerospace CSPS video series
- Tony Tyson presents to the National Academies' Board on Physics and Astronomy (BPA) for their Fall Meeting in November 2020
- The Aerospace Corporation's Space Policy Show had an episode on "Space Agenda 2021"
- The AAS and SIA teamed up again to do a 1-hour informational webinar for the satellite industry on astronomer's concerns about satellite constellations
- Virtual Press Conference on SATCON1 Workshop Report in August 2020
- A Science Friday interview "Who Owns the Night Sky?" with Aparna Venkatesan and James Lowenthal
- AAS 235 and AAS 236 presentations on satellite constellations
- Slides from Joel Parriott (AASPPD) that can at the end of the webinar on satellite constellations in May 2020
- Presentation by Patricia Cooper (SpaceX) from a webinar on satellite constellations in May 2020
- Presentation by Tony Tyson (Vera Rubin Observatory) from a webinar on satellite constellations in May 2020
- Presentation by Pat Seitzer (UMich) for a webinar on satellite constellations in May 2020
- Webinar: From Orbital Debris to GPS vs 5G: Decoding the FCC’s Role in Space Policy
- Aerospace Corporation's Center for Space Policy and Strategy Webinar Series
- Webinar: OneWeb’s Bankruptcy: Impacts and Implications for the Satellite Industry
- During the pandemic, AAS has a page to find live-streamed astronomy presentations and events, some of which cover satellite constellations
- The Committee on Astronomy and Astrophysics set up a Space Science Week 2020 page that has many useful presentations archived.
- Presentation by Tony Beasley (Director of NRAO) for a Hill briefing on satellite constellations in Mar. 2020
- Presentation by Piero Benvenuti (IAU) at COPUOS from Feb. 2020 - COPUOS_57th_STSC.pdf
- Press Conference at AAS 235 (Jan. 2020) "Astronomy Confronts Satellite Constellations"