Speaker
Description
Urban light pollution is a growing concern for astronomers worldwide, and Africa is no exception. Rapid urbanization in East Africa, especially around major cities such as Nairobi, has led to increased artificial sky-glow, which hampers ground-based astronomical observations and threatens future efforts in astronomy education, outreach, and research. In this study, wewill assess the extent of light pollution in and around Nairobi using satellite-derived night-time light data, ground-based sky brightness measurements, and citizen-science observations from local amateur astronomers. We will combine these datasets to map spatial gradients of sky brightness and identify “dark-sky corridors” where conditions remain suitable for stargazing
and astronomical imaging.
The study is expected to reveal increasing light-pollution trends across all cities studied. Brightness hotspots near industrial centres, highways, and commercial zones will be identified. Dark-sky corridors suitable for astronomical observatories are anticipated within 60–150 km of major cities. The project will produce the first detailed light-pollution maps for East Africa and provide a foundation for lighting policy guidelines.
Within 50 km of central Nairobi, sky brightness has increased by over 30% in the last decade, significantly reducing the number of observable stars compared to rural locations. However, we find that certain peri-urban and rural zones — especially within 80–120 km from the city — maintain acceptable sky darkness levels. We will discuss implications for the placement of small to medium observatories, outreach activities (for example, public stargazing events), and future astronomy-education initiatives in East Africa. Finally, we propose recommendations for local policymakers, urban planners, and astronomy stakeholders on mitigating light pollution (for example, smart lighting policies, “dark-sky reserve” designation, community awareness).
By quantifying light pollution trends and identifying viable observation zones, this work aims to support the growth of astronomy in the African continent.
Keywords: Light pollution, night-sky brightness, East Africa, urbanization, astronomy outreach, dark-sky zones.
| Stream | Education, Development and Outreach |
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