Seeing in the Dark: How Satellite Night Lights Revolutionize Open-Source Intelligence

How to Use NASA Night Lights Imagery to Track World Events - YouTube

NASA's Black Marble data transforms nighttime imagery into a powerful tool for tracking conflicts, disasters, and global activity

When the sun sets and cities illuminate against the darkness, satellites orbiting hundreds of kilometers above Earth capture something remarkable: a luminous map of human civilization that reveals far more than just where people live. NASA's Black Marble program, which provides freely available nighttime imagery through its Worldview platform, has emerged as an essential tool for open-source intelligence (OSINT) analysts tracking everything from war zones to natural disasters.

Unlike daytime satellite imagery, which shows physical infrastructure and terrain, nighttime observations reveal the pulse of human activity through artificial lighting. This capability has proven invaluable for understanding rapid changes in conflict zones, identifying power outages after natural disasters, and even monitoring maritime traffic patterns.

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SIDEBAR: How to Access NASA's Night Lights Data

Getting Started

1. Navigate to NASA Worldview at https://worldview.earthdata.nasa.gov/
2. When the interface loads, you'll see various data layer options including land surface disturbance, fire detection, and nighttime lights

Setting Up Your View 3. Select "Black Marble" nighttime data from the available layers 4. Click "Add Layers" and search for "Black Marble" to find additional visualization options 5. Enable the "Black Marble Nighttime Blue Yellow Composite" for clearest identification of light sources 6. Optionally enable "Black Marble Sensor Radiance" for black-and-white intensity views

Analyzing the Data 7. Use the timeline slider at the bottom to navigate through daily imagery 8. Skip cloudy days by scrolling through dates until you find clear observations 9. Zoom in to specific regions of interest using standard map controls

Comparing Over Time 10. Click "Start Comparison" to enable side-by-side date viewing 11. Set your "A" panel to a baseline date (before an event) 12. Set your "B" panel to a comparison date (during or after an event) 13. Use the central slider to compare changes in light emissions 14. Check multiple dates to confirm patterns aren't due to cloud cover or sensor anomalies

Advanced Features 15. Create animations showing daily changes over weeks or months 16. Use different layer combinations to identify vessels at sea 17. Export imagery or coordinates for further analysis

Tips for Accurate Analysis

• Always examine multiple dates to confirm consistent patterns
• Consider contextual factors: power outages, conflict camouflage, population displacement
• Cross-reference with other OSINT sources for comprehensive understanding
• Remember that cloud cover can obscure observations

No registration, software installation, or payment required—just an internet connection and web browser.

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SIDEBAR: Understanding Satellite Orbits and Revisit Times

Polar Orbits: The Path of Night Light Satellites

NASA's VIIRS instruments aboard Suomi NPP and NOAA-20 operate in sun-synchronous polar orbits—a special type of orbit that passes over the Earth's poles while maintaining a consistent local time during each pass. These satellites orbit at approximately 824 kilometers (512 miles) altitude, completing roughly 14 orbits per day.

Why Polar Orbits?

• Global Coverage: By orbiting pole-to-pole while Earth rotates beneath them, these satellites observe the entire planet systematically
• Consistent Lighting: Sun-synchronous orbits cross the equator at the same local solar time each day, ensuring consistent lighting conditions for daytime observations
• Nighttime Passes: The orbit is timed so satellites pass over regions during both day and night, with nighttime passes occurring around 1:30 AM local time

Revisit Time: How Often Can We See the Same Place?

For nighttime light observations, "revisit time" refers to how frequently a satellite can image the same location on Earth during darkness. Key factors include:

Daily Coverage: Suomi NPP and NOAA-20 each provide daily global coverage, meaning every location on Earth is imaged at least once per day. However, not every pass occurs during nighttime.

Overlap at Higher Latitudes: Near the poles, orbital paths overlap significantly. A location at 70° latitude might be observed during 4-6 different satellite passes per day, while equatorial regions might only be imaged during 1-2 passes.

Swath Width: VIIRS has a swath width of approximately 3,000 kilometers (1,860 miles), meaning it observes a 3,000-km-wide strip of Earth during each pass. This wide swath enables rapid global coverage.

The Two-Satellite Advantage: Having both Suomi NPP and NOAA-20 in orbit doubles observation opportunities. Their orbits are phased so they cover different areas at different times, improving temporal resolution.

Practical Implications for OSINT

Temporal Resolution: Most locations receive nighttime observations 1-2 times per day. This means analysts can track changes on a daily basis, though exact timing varies by latitude.

Cloud Cover Challenges: Even with daily coverage, persistent cloud cover can prevent observations for several consecutive days. This is why analysts check multiple dates to find clear imagery.

Time-Sensitive Events: For rapidly evolving situations (blackouts, conflicts), the ~12-hour gap between nighttime observations means some short-duration events might be missed.

Complementary Systems: Commercial satellites in different orbits can provide additional coverage. Some high-resolution systems operate in lower orbits (400-600 km) with narrower swaths, requiring multiple days to cover the same area but offering more detailed imagery.

Geostationary Alternative: While VIIRS uses polar orbits, some weather satellites occupy geostationary orbits (35,786 km altitude) where they remain fixed over one point on Earth. These provide continuous monitoring of a single hemisphere but lack the spatial resolution and nighttime sensitivity needed for detailed night light analysis.

Future Improvements: Next-generation satellites may include:

• Additional VIIRS instruments on more satellites for more frequent revisits
• Improved sensitivity for detecting dimmer light sources
• Better cloud-penetrating technologies using radar or thermal sensors
• Coordination between multiple satellite systems for near-continuous coverage

Understanding Observation Gaps

When using NASA Worldview, gaps in data can occur due to:

• Satellite maintenance or calibration periods
• Orbital mechanics creating longer intervals between observations at certain latitudes
• Data processing delays (typically 3-6 hours after acquisition)
• Solar interference during certain times of year

Analysts account for these factors by examining data patterns over weeks rather than single days, ensuring their conclusions reflect genuine changes rather than observation artifacts.

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Tracking Conflict Through Darkness

The power of nighttime satellite observations became starkly apparent during Russia's invasion of Ukraine in 2022. Black Marble data showed Ukrainian cities going dramatically dark as the conflict intensified. Mariupol, a key target in the early months of the invasion, nearly disappeared from nighttime maps between January and May 2022, with light emissions dropping precipitously as power infrastructure was damaged and residents implemented light discipline for safety.

Similar patterns emerged in Gaza following October 2023, where nighttime imagery revealed a complete disappearance of light emissions in areas that had previously shown strong illumination. These changes reflect the compound effects of infrastructure damage, fuel shortages, and electricity disruptions that accompany modern urban warfare.

The advantage of nighttime observations lies in their ability to provide near-real-time assessment of conditions on the ground without requiring physical access. While analysts must interpret these changes carefully—decreased lighting could indicate power outages, deliberate blackouts for camouflage, displacement of populations, or infrastructure destruction—the data provides an objective baseline for understanding the scale and geographic spread of disruptions.

Disaster Response and Humanitarian Applications

Beyond conflict zones, nighttime satellite data serves critical functions in disaster response. Following the devastating February 2023 earthquake in southern Turkey and Syria, Black Marble imagery revealed widespread blackouts in affected areas, with cities like Antakya showing considerably reduced light emissions immediately after the quake struck.

These observations help humanitarian organizations rapidly identify areas without power, which correlates with damage severity and helps prioritize emergency response. Unlike ground-based damage assessments, which can take days or weeks in disaster scenarios, satellite nightlight data becomes available within hours, providing crucial situational awareness when time is most critical.

The technique has applications beyond immediate disaster response. Researchers have used nighttime light data to estimate economic activity, track urbanization patterns, and assess recovery progress in post-disaster regions. The correlation between nighttime lighting and economic development is particularly strong, making these observations valuable for understanding long-term trends in addition to acute crises. Studies following Hurricane Maria in Puerto Rico in 2017 demonstrated how nighttime light observations could track the pace of electricity restoration across the island, providing objective metrics for recovery efforts.

A Window into Closed Societies

Perhaps nowhere is the stark reality revealed by nighttime satellite imagery more evident than along the Korean Peninsula. The border between North and South Korea appears as a sharp line of demarcation in Black Marble data, with South Korea's brightly illuminated landscape contrasting dramatically with North Korea's sparse lighting outside of Pyongyang. This visual representation of energy access and economic disparity tells a story that ground-based reporting alone cannot convey.

The nighttime data also reveals another dimension: maritime activity. Vessels at sea appear as points of light against the dark ocean, allowing analysts to track shipping patterns, fishing fleet movements, and naval activity. In areas like the Yellow Sea and the Korea Strait, this capability provides insights into maritime trade patterns and potential sanctions evasion. Researchers have used nighttime light data to detect illegal fishing operations and monitor compliance with international maritime regulations.

The Technology Behind the Observations

NASA's Black Marble product derives from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite and NOAA-20 satellite. VIIRS includes a "day-night band" capable of detecting low levels of visible light at night, from moonlight reflecting off clouds to the glow of a single ship hundreds of kilometers away.

The Worldview platform processes this raw data into several visualization products, including a blue-yellow composite that enhances contrast and makes it easier to identify specific light sources, and a black-and-white radiance product that shows the intensity of light emissions. Daily imagery allows analysts to track changes over time, though cloud cover can obscure observations on some days.

What makes Black Marble particularly valuable for OSINT is its accessibility. Unlike classified intelligence satellite systems or expensive commercial imagery, NASA provides this data freely through an intuitive web interface that requires no specialized software or training. Anyone with an internet connection can access the same observations that researchers and intelligence analysts use.

However, NASA's Black Marble is not the only nighttime light data source available. The Earth Observation Group at the Colorado School of Mines maintains the VIIRS Nightfire dataset, which specifically detects high-temperature sources like gas flares, volcanoes, and large fires. The National Oceanic and Atmospheric Administration (NOAA) provides its own VIIRS nighttime data products through various portals. For historical analysis, researchers often turn to the Defense Meteorological Satellite Program's Operational Linescan System (DMSP-OLS), which collected nighttime light data from 1992 to 2013, providing a valuable baseline for long-term studies.

Commercial satellite operators are also entering the nighttime observation market. Companies like Maxar Technologies and Planet Labs have begun offering nighttime imaging capabilities with higher spatial resolution than government systems, though at a cost. The European Space Agency's Copernicus program, while primarily focused on daytime observations, includes capabilities that complement nighttime light analysis.

Applications in Research and Policy

The scientific literature on nighttime light observations has expanded dramatically in recent years. Researchers have published studies correlating nighttime brightness with GDP, carbon emissions, population density, and even public health outcomes. A 2020 study in Scientific Data presented a harmonized global nighttime light dataset covering 1992-2018, enabling researchers to track changes in human activity patterns over nearly three decades.

Urban planners use nighttime light data to study the spatial distribution of economic activity and infrastructure development. Economists have developed models that use changes in nighttime brightness as a proxy for economic growth in regions where traditional economic data is unreliable or unavailable. Environmental scientists study light pollution patterns and their effects on ecosystems and human circadian rhythms.

The World Bank has incorporated nighttime light data into poverty mapping efforts, using the correlation between electrification and economic development to identify underserved areas. The United Nations uses similar data to track progress toward Sustainable Development Goals, particularly those related to energy access and sustainable cities.

The Growing OSINT Ecosystem

The use of nighttime satellite observations represents just one component of the expanding open-source intelligence landscape. Organizations like Bellingcat, the Atlantic Council's Digital Forensic Research Lab, and numerous academic institutions have pioneered techniques for combining multiple data sources—satellite imagery, social media analysis, flight tracking, maritime monitoring, and public records—to investigate events that were once the exclusive domain of government intelligence agencies.

The Center for Advanced Defense Studies (C4ADS) has used nighttime light data alongside other OSINT techniques to track sanctions evasion and illicit trade networks. Human Rights Watch and Amnesty International incorporate satellite analysis, including nighttime observations, into investigations of alleged human rights abuses. Journalists at major news organizations increasingly employ these tools to verify claims and provide context for breaking news stories.

This democratization of intelligence capabilities has created new opportunities but also raises important questions about privacy, interpretation, and the potential for misuse. Professional OSINT practitioners emphasize the importance of rigorous methodology, transparent sourcing, and careful interpretation of data—principles that apply equally to nighttime satellite observations.

Limitations and Future Directions

While nighttime satellite observations provide unique insights, analysts emphasize the importance of contextualizing this data with other information sources. A decrease in nighttime lighting could have multiple causes, and distinguishing between them requires understanding ground conditions, weather patterns, and local context.

Additionally, cloud cover remains a persistent challenge, sometimes obscuring observations for days at a time. Analysts must examine multiple dates to identify consistent patterns rather than relying on single observations that might be affected by atmospheric conditions or sensor anomalies. The spatial resolution of current systems—approximately 500 meters for VIIRS—limits the ability to identify specific buildings or small installations.

Future developments may address some of these limitations. NASA continues to refine its Black Marble algorithms to improve cloud detection and atmospheric correction. The launch of additional satellites with nighttime imaging capabilities will improve temporal coverage, reducing gaps caused by cloud cover. Advances in machine learning and artificial intelligence are enabling automated detection of changes in nighttime light patterns, potentially alerting analysts to significant events in near-real-time.

Research is also expanding into new applications. Scientists are exploring how nighttime light data can contribute to climate change research, refugee movement tracking, and even the detection of informal settlements and displaced populations. The integration of nighttime observations with other satellite data—thermal imagery, radar, and multispectral sensors—promises to provide even richer insights into human activity patterns.

Ethical Considerations and Responsible Use

As nighttime satellite observations become more sophisticated and widely used, questions about privacy and responsible use have emerged. While the relatively coarse resolution of current systems limits privacy concerns compared to high-resolution daytime imagery, the ability to monitor patterns of human activity over time raises important ethical questions.

Professional OSINT practitioners have developed guidelines for responsible use of satellite data, emphasizing the importance of verification, contextual understanding, and respect for individual privacy. The European Union's General Data Protection Regulation (GDPR) and similar frameworks in other jurisdictions are beginning to address how satellite observations should be used and what protections should apply.

Organizations using nighttime light data for human rights investigations face particular challenges in balancing transparency with the safety of sources and the communities they document. The Satellite Sentinel Project, which monitored conflict in Sudan, established protocols for responsible disclosure that have influenced how other organizations approach similar work.

Despite these limitations, the integration of nighttime satellite observations into the OSINT toolkit represents a significant expansion in analytical capabilities. As conflicts, disasters, and global events increasingly play out in real-time on social media and other open platforms, the ability to independently verify and contextualize these reports with objective satellite data has become invaluable.

The democratization of this technology—making sophisticated Earth observation capabilities available to journalists, human rights researchers, academic institutions, and concerned citizens—represents a fundamental shift in how we monitor and understand our world. In an era of increasing information manipulation, the impartial witness of satellites observing Earth's nighttime glow provides a powerful tool for truth-seeking and accountability.

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Sources

Primary Data Sources and Platforms

1. NASA Earth Observatory. "Black Marble - Night Lights 2012-2025." NASA Worldview. Accessed October 23, 2025. https://worldview.earthdata.nasa.gov/

2. Earth Observation Group, Colorado School of Mines. "VIIRS Nightfire." https://eogdata.mines.edu/products/vnf/

3. National Oceanic and Atmospheric Administration (NOAA). "VIIRS Day/Night Band Nighttime Lights." https://ngdc.noaa.gov/eog/viirs/download_dnb_composites.html

4. Earth Observation Group. "Version 4 DMSP-OLS Nighttime Lights Time Series." https://eogdata.mines.edu/products/dmsp/

Scientific Publications

5. Roman, M.O., Wang, Z., Sun, Q., Kalb, V., Miller, S.D., Molthan, A., et al. (2018). "NASA's Black Marble nighttime lights product suite." Remote Sensing of Environment, 210, 113-143. https://www.sciencedirect.com/science/article/pii/S003442571830110X

6. Román, M.O., Stokes, E.C., Shrestha, R., Wang, Z., Schultz, L., Carlo, E.A.S., et al. (2019). "Satellite-based assessment of electricity restoration efforts in Puerto Rico after Hurricane Maria." PLOS ONE, 14(6): e0218883. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0218883

7. Li, X., Zhou, Y., Zhao, M., & Zhao, X. (2020). "A harmonized global nighttime light dataset 1992–2018." Scientific Data, 7(1), 168. https://www.nature.com/articles/s41597-020-0510-y

8. Elvidge, C.D., Baugh, K., Zhizhin, M., Hsu, F.C., & Ghosh, T. (2017). "VIIRS night-time lights." International Journal of Remote Sensing, 38(21), 5860-5879. https://www.tandfonline.com/doi/full/10.1080/01431161.2017.1342050

9. Levin, N., Kyba, C.C.M., Zhang, Q., Sánchez de Miguel, A., Román, M.O., Li, X., et al. (2020). "Remote sensing of night lights: A review and an outlook for the future." Remote Sensing of Environment, 237, 111443. https://www.sciencedirect.com/science/article/pii/S0034425719305632

10. Chen, X., & Nordhaus, W.D. (2011). "Using luminosity data as a proxy for economic statistics." Proceedings of the National Academy of Sciences, 108(21), 8589-8594. https://www.pnas.org/doi/10.1073/pnas.1017031108

11. Henderson, J.V., Storeygard, A., & Weil, D.N. (2012). "Measuring economic growth from outer space." American Economic Review, 102(2), 994-1028. https://www.aeaweb.org/articles?id=10.1257/aer.102.2.994

Technical Documentation

12. NASA Goddard Space Flight Center. "Suomi NPP VIIRS Sensor." NASA. https://www.nasa.gov/suomi-npp/viirs-sensor/

13. NASA Earth Observatory. "Black Marble: NASA Looks at Earth's Night Lights." March 2017. https://earthobservatory.nasa.gov/features/NightLights

14. National Oceanic and Atmospheric Administration. "JPSS VIIRS Imagery." https://www.star.nesdis.noaa.gov/jpss/viirs.php

15. Cao, C., Xiong, J., Blonski, S., Liu, Q., Uprety, S., Shao, X., et al. (2013). "Suomi NPP VIIRS sensor data record verification, validation, and long-term performance monitoring." Journal of Geophysical Research: Atmospheres, 118(20), 11,664-11,678. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2013JD020418

OSINT and Application Studies

16. Bellingcat. "A Beginner's Guide to Identifying Burnt Villages in Darfur With Satellite Imagery." https://www.bellingcat.com/resources/how-tos/2016/10/03/identifying-burnt-villages-darfur-satellite-imagery/

17. Raleigh, C., Linke, A., Hegre, H., & Karlsen, J. (2010). "Introducing ACLED: An Armed Conflict Location and Event Data Set." Journal of Peace Research, 47(5), 651-660. https://journals.sagepub.com/doi/10.1177/0022343310378914

18. Witmer, F.D.W., & O'Loughlin, J. (2011). "Detecting the effects of wars in the Caucasus regions of Russia and Georgia using radiometrically normalized DMSP-OLS nighttime lights imagery." GIScience & Remote Sensing, 48(4), 478-500. https://www.tandfonline.com/doi/abs/10.2747/1548-1603.48.4.478

Policy and Development Applications

19. World Bank. "Using Night Lights Data to Measure Economic Development." World Bank Blogs. https://blogs.worldbank.org/

20. Jean, N., Burke, M., Xie, M., Davis, W.M., Lobell, D.B., & Ermon, S. (2016). "Combining satellite imagery and machine learning to predict poverty." Science, 353(6301), 790-794. https://www.science.org/doi/10.1126/science.aaf7894

21. Falchi, F., Cinzano, P., Duriscoe, D., Kyba, C.C.M., Elvidge, C.D., Baugh, K., et al. (2016). "The new world atlas of artificial night sky brightness." Science Advances, 2(6): e1600377. https://www.science.org/doi/10.1126/sciadv.1600377

Organizations and Resources

22. European Space Agency Copernicus Programme. "Sentinel Missions." https://www.copernicus.eu/en/about-copernicus/infrastructure/discover-our-satellites

23. Center for Advanced Defense Studies (C4ADS). "Using Open Source Data." https://c4ads.org/

24. Atlantic Council Digital Forensic Research Lab. https://www.atlanticcouncil.org/programs/digital-forensic-research-lab/

25. Berkeley Protocol on Digital Open Source Investigations. United Nations Office of the High Commissioner for Human Rights, 2022. https://www.ohchr.org/en/publications/policy-and-methodological-publications/berkeley-protocol-digital-open-source