Discover the Nightprint of your site.

Where is your site?

Search for your site or click the map to drop a pin. The tool will automatically retrieve light pollution data and nearby habitat information to inform the scoring.


Retrieving environmental data…
Your Nightprint
Site nocturnal sensitivity profile.
Nightprint v1.0 2026. A living methodology. Scores combine open environmental data with your site knowledge. For sites with high ecological sensitivity, specialist ecological assessment is recommended. Developed by Lightbahn.
Why Nightprint exists

For most of the history of artificial lighting, the question lighting designers have been trained to ask is: what do humans need to see? It is a reasonable question. It is also an incomplete one.

The night is not a neutral backdrop waiting to be illuminated. It is an ecological condition that has governed the behaviour of living organisms for billions of years. Approximately thirty percent of vertebrates and sixty percent of invertebrates are primarily nocturnal. The systems that move through the dark, insects navigating to flowers, bats following corridors between roost and foraging ground, birds correcting their position by starlight, soil organisms surfacing to do the work that keeps the ground alive, have no seat at the table when a lighting design brief is written. They never have.

The Nightprint is an attempt to give them one.

This is not a compliance tool. It does not produce a pass or fail. It is a conversation opener for more-than-human lighting design: a structured way of asking, before any lighting design decision is made, who else is present in the darkness of a specific place and what they stand to lose when a light is switched on. Humans are not the only stakeholders in the night. They are simply the only ones whose interests lighting design has historically been paid to consider.

The framework draws on the rapidly expanding science of Artificial Light at Night, a field that has grown from fewer than ten peer-reviewed studies per year in the 1990s to over one hundred annually by 2024. The evidence is now too substantial to treat as peripheral. This is version 1.0. It will change as practitioners use it, as the science develops, and as more-than-human lighting design becomes more mainstream in the profession. Contributions, challenges, and field applications are welcomed.

The seven dimensions

The Nightprint maps a site across seven dimensions. Each one names a community of stakeholders that artificial light affects and that conventional practice has historically not accounted for. The dimensions were chosen through deliberate consolidation: a set that a lighting design practitioner can score in a single working session using freely available data, where each dimension generates meaningfully different thinking, and where nothing ecologically significant disappears from view.

Six of the seven dimensions ask what a site needs protecting from artificial light. The seventh, civic and nocturnal identity, asks what it deserves. Including it prevents the framework from reading as purely restrictive and opens the question that often produces the most generative thinking, particularly when civic significance sits in tension with high ecological sensitivity.

01 Human wellbeing
Circadian health · glare · obtrusive light
Humans evolved under bright days and genuinely dark nights. When blue-rich light enters the eye after dusk it suppresses melatonin production, disrupts sleep architecture, and over time contributes to metabolic and cardiovascular risk. This is not a design preference. It is a documented biological response to a relatively recent environmental condition. This dimension is the one most lighting designers are already fluent in. The Nightprint keeps it present alongside all the others not because it needs advocacy but because it needs to share the frame with the six communities that follow.
Scoring uses: Observable site conditions. Proximity and density of residential use, hospital and care home adjacency, and existing ambient light levels assessed against Environmental Zone classification.

Limitations: Cannot assess actual illuminance at specific windows or building orientation. A full assessment requires photometric calculation against ILP GN01:2021 and BS EN 12464-2.
References: ILP Guidance Notes for the Reduction of Obtrusive Light (GN01:2021) · BS EN 12464-2:2014 · Blume, C., et al. (2019). Somnologie, 23, 147 to 156.
02 Nocturnal wildlife
Birds · bats · migratory and resident · dark corridors
Migratory birds navigate by starlight along flyways shaped by coastlines, river valleys, and ridgelines. These routes have been fixed for millennia. Human infrastructure has been built across many of them without reference to them, because they are invisible in daylight. Bats organise their entire existence around the structure of darkness. Their commuting corridors are learned routes that may have been used across generations. Even one lux at ground level can prevent light-averse species from using an established route. In the UK, all bat species carry full legal protection under the Wildlife and Countryside Act 1981.
Scoring uses: OpenStreetMap habitat detection and eBird citizen science data (species count and notable observations within 25km, last 14 days).

Limitations: Bat species identification requires acoustic survey. A score of 4 or 5 is a flag for specialist investigation, not a confirmed finding. BCT Good Practice Guidelines (5th edition, 2023) required for definitive assessment.
References: BCT Good Practice Guidelines for Bat Surveys, 5th ed. (2023) · Wildlife and Countryside Act 1981 · Conservation of Habitats and Species Regulations 2017 · Cabrera-Cruz, S.A., et al. (2018). Scientific Reports, 8, 3261 · eBird Basic Dataset, Cornell Lab of Ornithology. ebird.org
03 Fauna
Insects · pollinators · invertebrates · phototaxis
Insects navigate by the consistent position of natural light sources. When an artificial source appears in their environment they spiral toward it in an attempt to maintain a fixed angle, a behaviour called phototaxis. At the source they exhaust themselves, face predation, or die. Moths are the dominant nocturnal pollinators for many plant species. Studies published in 2021 confirmed that lit road verges support significantly fewer caterpillars than dark ones, with effects cascading upward through food webs to insectivorous bird populations. Broad-spectrum LEDs produce a peak in the blue wavelength range that causes significantly stronger phototaxis than warm amber sources. The energy efficiency transition the lighting industry celebrated has in many documented cases worsened the ecological impact of external lighting.
Scoring uses: OpenStreetMap habitat detection distinguishing managed green space from semi-natural or designated habitat within 300m. Woodland, unmanaged grassland, hedgerows, and nature reserves weighted more heavily than parks and gardens.

Limitations: Cannot assess specific invertebrate species present, population density, or light levels at which phototaxis becomes ecologically significant for the species assemblage at this site.
References: Boyes, D.H., et al. (2021). Science Advances, 7(35) · Knop, E., et al. (2017). Nature, 548, 604 to 607 · Van Langevelde, F., et al. (2018). Global Change Biology, 24(3), 925 to 932 · OpenStreetMap contributors. openstreetmap.org
04 Aquatic ecology
Freshwater · coastal · riparian habitats
Water is not a barrier to artificial light. It penetrates the surface and reaches organisms that have no evolved response to it. Zooplankton migrate vertically every night, rising to feed in darkness and sinking by day to avoid predation. Artificial light suppresses this migration and reduces the feeding efficiency of the entire food web above. Salmon alter their migration timing in response to riverside lighting. Coastal reef organisms have evolved to spawn on specific nights calibrated to lunar light cycles. The riparian margin, where water meets land, is among the most ecologically productive zones in any landscape and among the most sensitive to artificial light.
Scoring uses: OpenStreetMap waterway type classification with proximity bands of 50m and 100m applied.

Limitations: WFD ecological status is not available through open APIs and must be verified manually via the Environment Agency Catchment Data Explorer or equivalent national database.
References: Fobert, E.K., et al. (2023). Phil. Trans. Royal Society B, 379 · Nightingale, J.M., et al. (2006). Biodiversity and Conservation, 15(6), 2099 to 2111 · Environment Agency Catchment Data Explorer. catchmentbasedapproach.org · OpenStreetMap contributors. openstreetmap.org
05 Flora and soil
Plant phenology · soil microbiome · ground ecology
Plants measure the length of the night to know what time of year it is. This process, called photoperiodism, governs when a plant flowers, drops its leaves, and goes dormant. It depends on an uninterrupted dark period of the right duration. Urban trees under street lighting show delayed leaf senescence in autumn, creating misalignments with the insects and animals that depend on predictable seasonal cues. Below the surface, research published in 2024 and 2026 confirmed that artificial light at night alters earthworm communities, disrupts soil bacterial structure, and reduces the abundance of functional genes responsible for denitrification and methane oxidation. The night reaches underground.
Scoring uses: OpenStreetMap land use classification distinguishing woodland, meadow, unmanaged grassland, and nature reserves from managed parks and gardens.

Limitations: Cannot assess specific species composition, photoperiod sensitivity of individual species, or existing canopy-level illuminance. The soil ecology findings cited are recent and the field is still developing.
References: Cai, L., et al. (2026). Journal of Applied Ecology · Ffrench-Constant, R.H., et al. (2016). Proc. Royal Society B, 283(1833) · Bennie, J., et al. (2016). Journal of Applied Ecology, 53(2), 334 to 343 · OpenStreetMap contributors. openstreetmap.org
06 Dark sky and cultural commons
Skyglow · Bortle classification · sky heritage
Skyglow is the diffuse upward scattering of artificial light across an entire region. It is cumulative, largely irreversible at landscape scale, and visible hundreds of kilometres from its source. It has made the Milky Way invisible to one third of humanity and degraded the photon gradients that nocturnal organisms across every kingdom of life have used for billions of years. The natural night sky is also a cultural heritage resource. Its loss, like the loss of a language, is rarely noticed until it is already gone. One principle applies regardless of site location: a Bortle 9 city centre and a Bortle 2 rural site carry the same obligation to specify zero upward light output. Every contributor that excuses itself because the damage is already done is participating in the logic that created the problem.
Scoring uses: Sky brightness retrieved automatically from the Light Pollution Map database, based on the Falchi et al. (2016) world atlas using VIIRS satellite data.

Limitations: The database is updated periodically and may not reflect recent local changes. The satellite measurement captures skyglow at regional scale and does not account for highly localised dark areas.
References: Falchi, F., et al. (2016). Science Advances, 2(6) · Kyba, C.C.M., et al. (2017). Science Advances, 3(11) · Light Pollution Map. lightpollutionmap.info · IDA Model Lighting Ordinance. darksky.org
07 Civic and nocturnal identity
Urban significance · place value · nocturnal character
This is the only dimension that asks not what a site needs protecting from artificial light, but what it deserves from it. Some sites carry civic or cultural significance at night that is real and legitimate. At these sites the design of light is part of how a city understands itself and presents itself to its inhabitants. That is a responsibility that sits alongside, and sometimes in tension with, the six ecological dimensions above. The tension is not a problem to be resolved by compromising one or the other. It is the design brief.
Scoring uses: OpenStreetMap civic and heritage tag detection within 500m as a starting point. User judgement is the most important input on this dimension.

Limitations: Civic significance is inherently qualitative and contextual. OSM cannot assess a site's role in the nocturnal identity of a specific community.
References: Edensor, T. (2017). From Light to Dark. University of Minnesota Press · Narboni, R. (2004). Lighting the Landscape. Birkhäuser · OpenStreetMap contributors. openstreetmap.org
Two cross-cutting modifiers

Spectral composition. Blue-rich light above 4000K is significantly more ecologically harmful than warm sources across almost every dimension. The industry-wide LED transition improved energy performance and worsened ecological impact on many sites simultaneously. Colour temperature is not only an aesthetic choice. It is an ecological one.

Temporal pattern. Most ecological harm from artificial light is dose-dependent. A luminaire on an adaptive motion-responsive profile carries far lower ecological impact than one operating at full output from dusk to dawn. Adaptive control should be the default assumption. Continuous full-output operation should need to justify itself.

Open data sources
Light Pollution Map
Sky brightness and Bortle class derived from VIIRS satellite data. Falchi et al. (2016) world atlas methodology. lightpollutionmap.info
OpenStreetMap
Habitat detection, water body classification, civic and heritage tag identification. Queried via the Overpass API. openstreetmap.org · overpass-api.de
eBird
Bird species observations within 25km radius, last 14 days. Cornell Lab of Ornithology Basic Dataset. ebird.org
Full references

Anderson, S.J., et al. (2024). The ecological economics of light pollution. Remote Sensing, 16(14), 2591.

Bat Conservation Trust. Good Practice Guidelines for Bat Surveys, 5th edition (2023).

Bennie, J., et al. (2016). Artificial light at night causes top-down and bottom-up trophic effects on invertebrate populations. Journal of Applied Ecology, 53(2), 334 to 343.

Boyes, D.H., et al. (2021). Street lighting has detrimental impacts on local insect populations. Science Advances, 7(35).

BS EN 12464-2:2014. Light and lighting: Lighting of work places. Part 2: Outdoor work places.

Cabrera-Cruz, S.A., et al. (2018). Light pollution is greatest within migration passage areas for nocturnally-migrating birds. Scientific Reports, 8, 3261.

Cai, L., et al. (2026). Artificial light at night alters earthworm communities and soil aggregation. Journal of Applied Ecology.

Falchi, F., et al. (2016). The new world atlas of artificial night sky brightness. Science Advances, 2(6).

Ffrench-Constant, R.H., et al. (2016). Light pollution is associated with earlier tree budburst across the United Kingdom. Proceedings of the Royal Society B, 283(1833).

Fobert, E.K., et al. (2023). The impacts of artificial light at night on the ecology of temperate and tropical reefs. Philosophical Transactions of the Royal Society B, 379.

Holker, F., et al. (2010). Light pollution as a biodiversity threat. Trends in Ecology and Evolution, 25(12), 681 to 682.

Institution of Lighting Professionals. Guidance Notes for the Reduction of Obtrusive Light. GN01:2021.

International Dark-Sky Association. Model Lighting Ordinance with User's Guide. darksky.org.

Jain, A. (2018). More-than-Human Centred Design. Keynote address, IxDA Interaction18, Lyon. Superflux Studio. superflux.in.

Knop, E., et al. (2017). Artificial light at night as a new threat to pollination. Nature, 548, 604 to 607.

Kyba, C.C.M., et al. (2017). Artificially lit surface of Earth at night increasing in radiance and extent. Science Advances, 3(11).

US National Park Service (2026). Synthesis of Studies on the Effects of Artificial Light at Night. nps.gov/articles/effectsoflight.htm.

Van Langevelde, F., et al. (2018). Declines in moth populations stress the need for conserving dark nights. Global Change Biology, 24(3), 925 to 932.

Wildlife and Countryside Act 1981 (as amended). Conservation of Habitats and Species Regulations 2017.

Version and development

Nightprint v1.0. Published by Lightbahn, 2026. This is a living methodology. As practitioners apply the framework on real projects and share what they find, as the science develops, and as the conversation it is trying to start becomes more mainstream in the profession, the framework will be revised. The goal is not a fixed instrument. It is a shared and improving one.

Lightbahn is a lighting design practice committed to ecologically responsible and more-than-human design. lightbahn.com