01 / Lectures

When does a room end its day?

Evening arrives outside while the ceiling still shines like noon. Start with a simple question: how should light fit the person who lives with it?

Open Academy · 2026

Evening above a river: a warm horizon, buildings and the first lights — Evening light above a river. From the author’s personal archive.

The Academy’s author perspective

A person’s whole day

Behind individual luminaires, we often lose sight of a person’s whole day.

Home, the journey, work, a shop. Each place has its own light. The person has one day. Let’s look at it as a whole.

From “Light as a living environment” · translation

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01 / Time of day

One day. Different tasks.

Move the time control and explore how the purpose of light changes. The curve illustrates a changing schedule; it prescribes no illuminance values.

18:00

Relative intensity

Changing scheduleOne setting all day

Time of day

Evening

The room can wind down too. Background lighting and the light needed for reading can be considered separately.

Teaching diagram. The curve is neither a light measurement nor a biological response. A real design needs a schedule and measurements.

01Light source

The source, optics and spectrum. Natural daylight is part of the system.

02Control

The switch, brightness, schedule and ability to change a decision.

03Observation

The person, sensors or an agent track conditions and outcomes.

Start with the fundamentals

9 lessons · 5 materials

04 / 09

Biology and time of day

The same room can call for different choices in the morning and before sleep. A precise discussion records timing, duration, spectrum and light at eye level.

An expert consensus published in PLOS Biology proposes melanopic EDI guidance at eye level for healthy adults with daytime routines: at least 250 lx during the day, no more than 10 lx for the three hours before bed and no more than 1 lx during sleep. These are melanopic quantities. A conventional lux reading alone cannot establish them.

The recommendations have a defined scope. Children, shift work and clinical applications require separate consideration. A questionnaire cannot calculate an individual physiological response.

Melanopic DER relates photopic illuminance to melanopic EDI for a specified spectrum: mEDI = Eᵥ × DER. At 300 lx and DER 0.7 the result is 210 lx mEDI. Both inputs must describe the same spectrum at eye position. Daylight, reflections and a different dimming mode may change the inputs.

Compare two sources at 300 lx: DER 0.7 gives 210 lx mEDI, and DER 0.4 gives 120. This does not establish an overall source ranking. Purpose, time, duration, geometry and visual requirements still matter. Colour temperature alone cannot establish DER.

The 2022 Brown et al. consensus offers reference levels for healthy adults on daytime schedules: at least 250 lx mEDI by day, at most 10 during the three hours before bed, and at most 1 during sleep. These are contextual recommendations. Childhood, shift work and clinical applications require separate consideration.

Practice: select three periods in your day, record eye position, sources and known measurements, then build a laboratory profile. If DER is unmeasured, record the gap and a measurement plan. Time outside a selected reference helps describe the schedule; it does not predict the state of the body.

Key ideaKeep the source and scope alongside each recommendation.

Human practice

Describe one real situation related to this topic. Separate observations from assumptions and list the evidence needed to check them.

Agent assignment

Describe the lighting day. Record time outdoors, evening lighting and sources present during sleep. Label observations and assumptions separately.

S01 · CIE PS 001:2024 S02 · PLOS Biology · 2022 S03 · CIE S 026:2018 · α-opic Toolbox

Editorial teaching text. Check scientific claims against the cited primary sources; the project framework is identified in the text.

Markdown ↓Next lesson →

Workshop Laboratory Researchers

Core materials

Condensed thematic editions of the project documents for the Academy. Core ideas are retained and research assumptions are identified.

M01Project principlesDoctrine: core principles

Based on “Doctrine (core)” · Academy edition

Engineering serves the support of life, human comfort and a manageable relationship with the environment.

Light and living systems

Light is considered a factor in vision, biological rhythms and interaction with the environment. Mood, attention and subjective well-being are research topics. Each proposed effect requires defined conditions and a method of measurement.

Natural dynamics

Dawn, daytime, sunset, night, clouds and shadows provide a starting point for design. Spectrum, intensity, direction and distribution can change. The value of each pattern must be tested for the activity and person.

Spectrum and electromagnetic environment

The doctrine seeks a suitable spectrum and a controlled electromagnetic environment. This is a project principle. Turning it into a specification requires measurable quantities, operating limits and a review of applicable standards. “Full spectrum” alone does not establish quality or safety.

AI, person and physician

The person sets goals, reports comfort and retains control. The agent uses permitted data, proposes actions and explains them. A physician participates in clinical tasks and defines medical constraints. Predictive control must account for error and verify outcomes.

Goals and criteria

The project aims to reduce excessive strain and support sleep, performance and subjective well-being. These outcomes are assessed separately. Improvement in one does not establish improvement in the others.

S01 · CIE PS 001:2024 S02 · PLOS Biology · 2022 S03 · CIE S 026:2018 · α-opic Toolbox S06 · WHO · Electromagnetic fields

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M02Overall visionOur view of light

Based on Take on light · 2 March 2025 · Academy edition

A lighting environment can respond to daily rhythm, activity, position and feedback. The concept connects sources, optics, controls and intelligence.

Rhythm and space

Design considers time and place: task surface, field of view, surrounding light, daylight and sleep conditions. Local lighting must work with contrast and visual comfort. Dimness is an intentional operating mode.

An artificial sky

The concept proposes directed and diffuse light, changing angles, cloud patterns and shadows. This is a research direction. Evaluation compares dynamic and baseline conditions while controlling illuminance, spectrum, glare and duration.

Families of light sources

Plasma, LED and other sources are assessed through measured properties of actual devices. Comparisons include spectrum, control, heat, noise, temporal modulation, maintenance and life. A technology label alone establishes no health advantage.

Power and fields

Wired power, batteries, a remote source and wireless power are engineering alternatives. Each requires assessment of losses, heat and electromagnetic fields during operation. Wireless transfer uses electromagnetic interaction; removing a cable does not remove the field.

Observation and prediction

Preferences and voluntary reports add to environmental data. Pulse, facial expression or activity do not uniquely determine emotions or the appropriate lighting. Models must express uncertainty, test predictions and allow an action to be cancelled.

Verification programme

A measured baseline, defined intervention, observation period and advance criteria are needed. Artificial skies, medical outcomes, new-source advantages and predictive control of personal state each need separate evidence. Prototypes are assessed through actual operation.

S01 · CIE PS 001:2024 S03 · CIE S 026:2018 · α-opic Toolbox S05 · NASA · Lighting for people and plants S06 · WHO · Electromagnetic fields

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M03Research programmeTLI / TLB: scientific direction

Based on TLI-TLB · Academy edition

Lighting reform encompasses understanding, daily habits, environmental design and control methods.

Everyday life

Homes, workplaces, education, shops and the city form connected parts of a lighting day. The learning goal is to describe, assess and improve that routine together with an agent.

Population health

Sleep, attention, performance, stress and well-being are research topics. Immune and reproductive processes require separate research questions. Population conclusions require suitable study designs and control of other factors.

Deep space and extreme environments

The long-term question concerns light in a designed life-support environment. For the Academy this includes reconstructing a biome and maintaining connected life cycles. Practical models use known organisms and processes; obtaining life from non-living matter remains a separate scientific question.

Scientific organisation

AI supports search, memory, analysis and model comparison. A scientific team formulates questions, assesses evidence and verifies results. Electrical engineering, lighting, biology, environmental design and operations use a shared data framework.

Research and application

Deployment creates observations and questions. Research refines settings, equipment and quality criteria. Reproducible results gradually inform methods, teaching and practice. Scaling retains the boundaries of verified findings.

S01 · CIE PS 001:2024 S04 · ESA · MELiSSA · Closed Loop Concept S05 · NASA · Lighting for people and plants

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M04Engineering architectureA unified lighting environment

Based on the explanatory note on a unified lighting environment · Academy edition

A territory is considered through its combined light exposure: streets, transport, housing, workplaces and public spaces.

What is controlled

The scope includes sources, optics, power, controls, schedules and movement. Measurements describe actual outdoor and indoor conditions. Each system retains its responsible operator and operational constraints.

Coordinated settings

Control considers time, weather, presence and activity. Outdoor, transport and indoor lighting are coordinated where the task justifies it. Transitions preserve required visibility, manual control and recovery after failure.

Light, dimness and darkness

Managed darkness is part of the environment. Each setting requires an account of visibility, operating hours and light reaching neighbouring areas. Reduced intensity is supported by a survey and verification of conditions.

Renewal and reuse

Installation history covers inspection, cleaning, repair, adjustment, replacement and reuse of suitable equipment. Relocated devices require a fresh condition and suitability check. Renewal follows a measurable reason.

Diagnostics and feedback

Surveys, measurements and reports help identify conflicting settings. Changes are logged in the environmental passport. Before-and-after checks account for weather, season, traffic and activity.

Transfer between locations

The architecture can serve different territories. Dense cities, suburbs, mountain routes and polar sites have different requirements. Shared elements are data structure, quality verification, local responsibility and explainable control.

S01 · CIE PS 001:2024 S03 · CIE S 026:2018 · α-opic Toolbox

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M05Space and habitable environmentsLight in spacecraft

Based on the technical review of 31 August 2026; sources checked on 15 September 2026 · Academy edition

Taking terrestrial life into space means understanding the conditions it needs. On a spacecraft, lighting must fit sleep, work, visibility, instruments and biological cycles. They become parts of one engineering task.

Avoid carrying accumulated engineering mistakes into space.

SpaceX cabin concept: a circular compartment, seats and lighting strips along the walls — SpaceX · interior concept. The image shows a layout; flight lighting specifications cannot be determined from it. Original SpaceX image

What should be reproduced?

Nature provides a starting point: day and night, direction, spectrum, shadows and gradual transitions. Design turns that example into testable requirements. Continuous bright light, spill into sleeping areas and controls that people cannot override deserve early attention. Benefits of a particular solution must be tested under stated conditions.

The ISS: a daily rhythm within an orbital rhythm

The ISS experiences roughly 16 sunrises per Earth day while its crew follows a GMT schedule. NASA’s Lighting Effects studied the switch to LEDs with adjustable intensity and colour. The ESA/SAGA Circadian Light cabin experiment followed a sleep schedule. Operational equipment and an experimental installation have different purposes and status.

S09 · NASA · ISS Lighting Effects · 2017 S10 · ESA · Circadian Light · 2023

What NASA measures

JSC Lighting Lab works with lamps, cameras, glare and shadows, modelling orbital and surface environments. Its tools include Radiance and Zemax. For the Academy, this illustrates how scene calculations can be combined with measurements and human evaluation.

S07 · NASA JSC · Lighting Lab

Light at the eye

NASA-STD-3001, Volume 2, Revision F, dated 14 July 2026, includes circadian lighting specifications. Two parameters from Table 8.7-2 appear below. Application requires the full standard and measurement conditions.

S08 · NASA-STD-3001 · Volume 2 · Revision F

Two NASA circadian lighting parameters

Mode	Melanopic EDI, lx	Melanopic DER
General lighting during waking hours	≥ 250	≥ 0.7
Pre-sleep	8 ± 2	≤ 0.3

At the cornea in the vertical plane; both conditions must hold together. These are specifications for NASA human-rated systems. Personal home recommendations require a separate assessment.

What the SpaceX concept shows

The supplied illustration shows extended lighting strips, pale surfaces and light around the compartment perimeter. These features allow discussion of placement and possible reflections. Assessment requires spectra, photometry, operating modes, eye positions, screen behaviour and emergency power. The review and image do not supply those data. A proposed lighting architecture can serve as a design assignment.

Three tasks in one spacecraft

People need visibility, comfort and lighting coordinated with their schedule. Cameras and navigation need discernible detail, controlled reflections and compatibility with imaging settings. Plants need their own lighting conditions. A shared model should account for each subsystem’s power and heat, light spill and failure behaviour. This is the Academy’s proposed engineering framework.

Plants and living light

NASA uses Veggie and Advanced Plant Habitat for plant research in controlled environments. UMAMI studies a squid and its luminous bacterial partners. Bioluminescence is part of the living system under investigation. These projects provide insufficient evidence to justify illuminating a crew compartment with living organisms.

S11 · NASA · UMAMI S13 · NASA · Plant Biology Hardware

What to test on Earth first

Start with one autonomous compartment: define geometry, sources, schedules, human positions and system states. Compare modes, check light spill into sleeping areas, camera operation and manual override. Consider lighting alongside noise, air and temperature. Ground testing can reveal a mistake before it becomes part of a spacecraft.

Astronaut Moments cover: an astronaut in a medical coat and a spacesuit

Astronaut Moments · Anil Menon

NASA describes his experience as SpaceX’s first flight surgeon. He launched to the ISS aboard Soyuz MS-29 on 14 July 2026. This offers biographical context for medicine in human spaceflight.

Watch on YouTube NASA biography

S07 · NASA JSC · Lighting Lab S08 · NASA-STD-3001 · Volume 2 · Revision F S09 · NASA · ISS Lighting Effects · 2017 S10 · ESA · Circadian Light · 2023 S11 · NASA · UMAMI S12 · NASA · Anil Menon S13 · NASA · Plant Biology Hardware

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How the Academy works

One subject, two ways to learn

People receive an explanation and a practical exercise. Agents receive the same knowledge, a data structure and acceptance criteria. Tasks progress from choosing a lamp to managing an environment.

Daylight and darkness

The programme covers natural and electric light, windows, screens, timing and sleep conditions. Laboratory questions extend to plants, animals and the night environment.

Knowledge that can be revised

Each claim keeps its source, date and evidence status. New findings should update lessons, agent instructions and the rating method.

Space perspective

What kind of day will we take with us?

Spacecraft lighting connects vision, crew schedules and living systems. Explore ISS experience, NASA’s approach and a SpaceX interior concept.

SpaceX · Space and habitable environments

Light at different scales

From a light beside a plant to the lights of an entire city. A photograph helps pose a question; a measurement helps answer it.

Melbourne’s city lights trace a network of streets around a dark bay, seen from the ISS. — Melbourne at night. Don Pettit photographed the city from the ISS on 9 October 2024. NASA / Don Pettit

Dwarf tomato plants under pink light in the Veggie facility aboard the ISS. — Light for growth: tomatoes in the ISS VEG-05 experiment, 5 February 2023. NASA

Low sunlight illuminates glaciers and mountains in West Antarctica, casting long shadows over snow. — Light and landforms in West Antarctica. Michael Studinger, NASA IceBridge, 29 October 2014. Michael Studinger / NASA Operation IceBridge

Self-check: 12 questions

Formulate your answer, then reveal the explanation. A learning check with no certification.

1. Can watts describe light quality?

Power describes consumption. You need photometry, geometry and the task.

2. Does identical CCT mean an identical spectrum?

No. Obtain the spectrum or measured DER for the operating mode.

3. 300 lx with DER 0.7: what is mEDI?

210 lx mEDI, provided the values refer to the same point and spectrum.

4. Can desk lux represent eye exposure?

Measure separately at the eye position and viewing direction.

5. Does 250 lx mEDI guarantee good sleep?

No. It is a daytime consensus reference for healthy adults on daytime schedules, not an individual prediction.

6. What if DER is unknown?

Keep it unknown and request spectral measurement. Do not infer it from CCT.

7. Is phone video sufficient for flicker assessment?

No. Request a report with PstLM, SVM, instrument and dimming mode.

8. Can a red-light protocol be transferred to an ordinary lamp?

Do not transfer findings without matching wavelength, dose, timing and study population.

9. 400 m² × 12 W/m² × 6000 h: how much energy?

28,800 kWh per year. A 15% reduction equals 4,320 kWh.

10. Is saving energy while impairing visibility a success?

Check service preservation and acceptance criteria first. A cost difference alone is insufficient.

11. Does a completed passport prove lighting quality?

No. It records declared data coverage. Verifiable measurements and context are still needed.

12. What may an agent do with a passport?

Propose checks and calculate within its mandate. A passport does not authorise equipment control.

09 / Intelligence

Light Academy should know what changed today

Research, standards, equipment, prices and lighting practice.

Explore the section