Letters of Intent received in 2022

LoI 2024-2180
Focus Meeting: Ecological, Human Health, and Astronomical Collaboration to Protect the Night Sky

Date: 5 August 2024 to 16 August 2024
Category: Focus meetings (GA)
Location: Cape Town, South Africa
Contact: James Lowenthal (jlowenth@smith.edu)
Coordinating division: Division B Facilities, Technologies and Data Science
Other divisions: Division C Education, Outreach and Heritage
Co-Chairs of SOC: James Lowenthal (Smith College)
Connie Walker (NOIRLab)
Angel Otarolo (ESO)
Chair of LOC: Ramatholo Sefako (SFAO)



Collaboration among astronomers, ecologists, and human health experts to address light pollution (LP) and artificial light at night (ALAN).
Development of effective and scaleable strategies and policies to control LP and ALAN.
Implementation of recommendations from UN/IAU/IAC Dark & Quiet Skies 2 report.



On behalf of the Organizing Committee of IAU Commission B7 on Protection of Existing and Potential Observatory Sites, I submit via this Letter of Intent our plan to propose a Focus Meeting on “Ecological, Human Health, and Astronomical Collaboration to Protect the Night Sky” to take place at the IAU General Assembly in 2024.

The Focus Meeting just hosted last month at IAU GA 2022 in Busan, South Korea
by C.B7 on "Towards a World Standard for Dark and Quiet Sky Protection” provided a successful and thorough perspective on the status of ground-based light pollution; techniques and programs for measuring and characterizing it in various regions and countries around the world; and policies and strategies for combating it.

Two clear themes that emerged from the presentations and discussions at that Focus Meeting were (1) the rapid continuing growth of light pollution worldwide, including near professional astronomical observatories; and (2) the need for astronomers to work much more closely with ecologists, environmental organizations, and human health advocates towards their shared goal of reducing light pollution and the adverse effects of artificial light at night (ALAN). While astronomers may be especially tuned in to the negative effects of light pollution because of their ongoing intimate familiarity with the night sky, the scientific study of ecological and human health consequences of ALAN has blossomed in the last 20 years. It is now widely accepted that ALAN poses serious risks to individual organisms, species and ecosystems. For example, the International Union for the Conservation of Nature issued in 2021 Resolution 084 on Taking action to reduce light pollution; World Migratory Bird Day adopted for its 2022 theme the issue of light pollution’s effects on bird migration; and the Sierra Club revised and strengthened its position on light pollution. On the human side, the American Medical Association issued in 2016 a summary of scientific studies demonstrating negative effects on human health of light pollution, especially the blue-rich white LEDs that now dominate the commercial lighting market.

The ecological and human health impacts of ALAN were studied and summarized in 2020 by the BioEnvironment Working Group of the IAU/UN/IAC Dark & Quiet Skies conference. The following year, the Dark & Quiet Skies 2 conference extended that work to make policy recommendations to the UN Committee on the Peaceful Uses of Outer Space (UN COPUOS). As a result of those reports, UN COPUOS has agreed to include light pollution, both ground-based and due to Earth-orbiting satellites, on its agenda on an ongoing basis.

The science is clear: light pollution poses serious threats to research astronomy, human health, and biological organisms of all kinds, in addition to threatening the cultural heritage of the Milky Way and a naturally dark starry night sky. What is not so clear is how, through public policy, to stop and reverse the apparently inexorable growth of light pollution.

We propose a focus meeting that brings together advocates for dark skies and the control of light pollution and ALAN from three major realms: astronomers, ecologists, and human health experts. While we astronomers traditionally have approached light pollution control on our own, it is past time that we recognize our failure to stem the tide of ALAN creeping around the world. We must also recognize that it’s not enough for us to be right scientifically; we also need to be savvy politically, and we need to be strategic. Our most natural partners in the fight to save the night are experts in ecological and human health sciences. Those potential allies bring two major strengths to our common efforts: (1) their issues are of broad concern to the public and to decision makers worldwide; and (2) they have more political experience, institutional organization, and clout than astronomers alone. When Greenpeace and the United Nations Environmental Program start promoting the preservation of the night sky as a core value, we’ll know we’re getting the message across at the high levels that are necessary for effective action.

We propose a two-day, 9-hour Focus Meeting with a strong emphasis on strategizing and problem-solving. Rather than the normal scientific format of 90% talks and 10% discussion, we envision a more interactive format with perhaps ⅓ scientific talks and ⅔ organized discussion, break-out sessions, and focused planning. We have enough science behind us already to identify the problem; now we need to find solutions in the public policy realm worldwide.

For example, the D&QS2 report recommended to the UN a two-prong approach to combating light pollution: (1) the fixture-by-fixture approach (full shielding, warm colors, low light levels…) that we’ve pursued for decades to only limited success; and (2) a new, regional “harm threshold” approach borrowing from air and water quality control districts that would specify limits to acceptable harm from light pollution, such as sky glow, beyond which mitigation would be required. How will national and other governments implement such policies? What are the relevant agencies in each country hosting major astronomical observatories? What lessons can we learn from our colleagues in ecological conservation and public health policy?

Light pollution from ALAN poses arguably the greatest known threat to the science of astronomy. We are deeply committed to finding effective solutions to this existential threat. We believe the approach proposed here will allow us to gather crucial up-to-date information, help create a synergistic alliance with experts in the ecology and human health areas, and ultimately help us devise effective strategies towards our common goal of reducing ALAN. We hope you agree, and we welcome your feedback and hope for your support.