Free tools · NASA Black Marble, night light

Night light in City of Johannesburg

Night light seen from space, 2025: brightness 22.1 nW/cm²/sr on average, 98% of the land lit. 9.1% brighter than 2024; 11% darker than 2012.

Night light is the light a satellite sees from space at about 1:30 in the morning: street lights, buildings, mines, factories, harbours and fires. NASA takes out moonlight, haze and stray light, leaves out cloudy nights and sets faint glow to zero. Brightness is the light given off, in nanowatts per square centimetre per steradian (nW/cm²/sr), averaged over the place; “lit” is the share of the land giving off 1 or more, twice the faint glow NASA treats as noise.

What it is not: it cannot tell the grid from solar or a generator, who pays for the light, how many people live there or how well off they are. A load-shedding month mixes dark nights with lit ones, fires and flares can light a month up, and a cloudy month rests on fewer nights.

2025

22.1Average brightnessnW/cm²/sr, NASA’s yearly product
98%Of the land lit86% bright (5 nW/cm²/sr or more)
11% darkerAgainst 20122012: 24.9 nW/cm²/sr, 97% lit

2026 so far (10 months, from the monthly figures): brightness 23.8 nW/cm²/sr, 99% lit. NASA’s yearly figure for 2026 comes early next year.

Every year since 2012

Each year’s average brightness (nW/cm²/sr) from NASA’s yearly product. Bars start at zero.

Show the numbers

Night light each year, 2012 to 2025: every figure
When or what	Figure
2012	brightness 24.9 nW/cm²/sr, 97% lit
2013	brightness 24.6 nW/cm²/sr, 97% lit
2014	brightness 24.5 nW/cm²/sr, 97% lit
2015	brightness 24.0 nW/cm²/sr, 98% lit
2016	brightness 24.0 nW/cm²/sr, 97% lit
2017	brightness 24.0 nW/cm²/sr, 97% lit
2018	brightness 23.5 nW/cm²/sr, 97% lit
2019	brightness 23.2 nW/cm²/sr, 97% lit
2020	brightness 21.8 nW/cm²/sr, 97% lit
2021	brightness 21.6 nW/cm²/sr, 97% lit
2022	brightness 20.5 nW/cm²/sr, 97% lit
2023	brightness 18.7 nW/cm²/sr, 98% lit
2024	brightness 20.3 nW/cm²/sr, 98% lit
2025	brightness 22.1 nW/cm²/sr, 98% lit

Month by month

Average brightness each month since January 2012 (nW/cm²/sr). Shaded: 2022 and 2023, the years of the heaviest load-shedding. A gap is a month seen too little.

Every month since January 2012brightness, nW/cm²/sr

Year	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2026	22.9	23.2	25.3	23.8	21.8	23.7	25.2	23.7	24.6	24.3
2025	20.7	19.6	19.7	20.5	21.9	21.8	22.6	23.6	23.9	22.2	25.2	22.3
2024	19.3	17.6	18.7	18.7	19.2	19.7	22.4	23.1	20.6	22.1	20.7	21.0
2023	17.6	18.0	19.5	18.1	17.2	19.8	18.4	20.6	18.9	19.0	17.2	19.3
2022	21.4	19.5	21.8	19.5	20.1	20.6	20.7	22.9	19.7	20.6	20.6	18.9
2021	22.0	22.2	21.4	21.3	21.8	21.2	21.4	23.0	23.2	21.1	19.4	21.5
2020	20.6	22.2	21.1	21.5	21.4	21.1	22.3	23.3	21.4	21.5	21.4	24.6
2019	24.5	21.6	21.8	21.4	23.0	23.6	22.8	24.8	24.3	23.8	22.6	24.7
2018	24.3	22.4	22.4	22.4	22.5	23.5	23.6	24.3	24.0	24.0	25.2	22.7
2017	23.6	23.4	23.6	24.4	23.7	24.1	24.2	25.2	25.0	24.0	24.5	21.5
2016	22.4	21.5	23.0	23.9	23.8	23.8	24.1	24.9	24.9	24.2	27.7	24.7
2015	22.1	22.4	24.0	23.6	24.5	24.3	23.7	24.6	25.9	24.1	23.7	23.7
2014	25.0	22.0	23.3	23.9	24.0	23.8	24.7	25.6	25.8	25.5	24.3	25.0
2013	24.7	24.1	25.4	23.9	24.4	24.7	24.9	24.8	25.8	24.4	24.6	24.4
2012	25.2	24.2	25.4	25.1	25.1	24.1	25.0	25.6	25.2	24.8	25.9	24.1

Hover or tap a month for its lit share, how much NASA filled from earlier months and how many clear nights it rests on. Every figure is also in the API.

Every year

Year	Brightness (nW/cm²/sr)	Lit	Bright	Filled
2025	22.1	98%	86%	0%
2024	20.3	98%	84%	0%
2023	18.7	98%	83%	0%
2022	20.5	97%	84%	0%
2021	21.6	97%	83%	0%
2020	21.8	97%	82%	0%
2019	23.2	97%	83%	0%
2018	23.5	97%	83%	0%
2017	24.0	97%	83%	0%
2016	24.0	97%	82%	0%
2015	24.0	98%	82%	0%
2014	24.5	97%	81%	0%
2013	24.6	97%	81%	0%
2012	24.9	97%	81%	0%

Lit: the share of the land giving off 1 nW/cm²/sr or more. Bright: 5 or more. Filled: the share NASA filled from earlier months for want of a clear night.

Its 135 wards, 2025by ward number

Ward 110.4, 100% lit
Ward 214.4, 100% lit
Ward 313.5, 100% lit
Ward 410.6, 100% lit
Ward 52.4, 62% lit
Ward 65.6, 100% lit
Ward 716.0, 100% lit
Ward 89.2, 100% lit
Ward 912.1, 100% lit
Ward 1019.1, 100% lit
Ward 1116.5, 100% lit
Ward 1230.7, 100% lit
Ward 1320.9, 100% lit
Ward 1427.8, 100% lit
Ward 1535.0, 100% lit
Ward 1631.7, 100% lit
Ward 1721.5, 100% lit
Ward 1822.1, 100% lit
Ward 1927.6, 100% lit
Ward 2035.2, 100% lit
Ward 2138.1, 100% lit
Ward 2229.1, 100% lit
Ward 2320.8, 100% lit
Ward 2429.0, 100% lit
Ward 2530.2, 100% lit
Ward 2641.5, 100% lit
Ward 2747.4, 100% lit
Ward 2835.5, 100% lit
Ward 2922.9, 100% lit
Ward 3026.1, 100% lit
Ward 3132.3, 100% lit
Ward 3225.2, 100% lit
Ward 3333.7, 100% lit
Ward 3435.2, 100% lit
Ward 3529.6, 100% lit
Ward 3631.1, 100% lit
Ward 3728.5, 100% lit
Ward 3831.8, 100% lit
Ward 3919.0, 100% lit
Ward 4032.2, 100% lit
Ward 4134.4, 100% lit
Ward 4232.9, 100% lit
Ward 4329.0, 100% lit
Ward 4421.6, 100% lit
Ward 4532.3, 100% lit
Ward 4628.4, 100% lit
Ward 4727.1, 100% lit
Ward 4824.6, 100% lit
Ward 4912.7, 100% lit
Ward 509.2, 100% lit
Ward 5135.4, 100% lit
Ward 5228.6, 100% lit
Ward 538.0, 100% lit
Ward 5435.1, 100% lit
Ward 5532.6, 100% lit
Ward 5632.8, 100% lit
Ward 5721.7, 100% lit
Ward 5841.7, 100% lit
Ward 5962.7, 100% lit
Ward 6068.5, 100% lit
Ward 6137.4, 100% lit
Ward 6258.9, 100% lit
Ward 6356.2, 100% lit
Ward 6437.6, 100% lit
Ward 6533.9, 100% lit
Ward 6625.9, 100% lit
Ward 6743.5, 100% lit
Ward 6824.9, 100% lit
Ward 6932.2, 100% lit
Ward 7025.3, 100% lit
Ward 7126.3, 100% lit
Ward 7233.5, 100% lit
Ward 7333.6, 100% lit
Ward 7437.2, 100% lit
Ward 7547.6, 100% lit
Ward 7642.6, 100% lit
Ward 7726.4, 100% lit
Ward 7826.9, 100% lit
Ward 7927.3, 100% lit
Ward 8027.7, 100% lit
Ward 8131.1, 100% lit
Ward 8228.9, 100% lit
Ward 8323.8, 100% lit
Ward 8427.7, 100% lit
Ward 8527.0, 100% lit
Ward 8627.9, 100% lit
Ward 8732.9, 100% lit
Ward 8821.2, 100% lit
Ward 8930.0, 100% lit
Ward 9040.6, 100% lit
Ward 9147.1, 100% lit
Ward 9224.6, 100% lit
Ward 9341.3, 100% lit
Ward 9417.0, 100% lit
Ward 9511.7, 100% lit
Ward 9610.1, 100% lit
Ward 9718.7, 100% lit
Ward 9830.1, 100% lit
Ward 9925.7, 100% lit
Ward 10030.1, 100% lit
Ward 10129.3, 100% lit
Ward 10233.3, 100% lit
Ward 10339.2, 100% lit
Ward 10430.7, 100% lit
Ward 10544.4, 100% lit
Ward 10634.5, 100% lit
Ward 10752.1, 100% lit
Ward 10842.3, 100% lit
Ward 10934.6, 100% lit
Ward 11030.5, 100% lit
Ward 11132.3, 100% lit
Ward 11217.1, 100% lit
Ward 11313.3, 100% lit
Ward 11416.5, 100% lit
Ward 11526.5, 100% lit
Ward 11643.6, 100% lit
Ward 11729.5, 100% lit
Ward 11829.3, 100% lit
Ward 11914.1, 100% lit
Ward 12016.8, 100% lit
Ward 1214.5, 70% lit
Ward 1229.1, 100% lit
Ward 12354.5, 100% lit
Ward 12438.1, 100% lit
Ward 12510.4, 100% lit
Ward 12628.1, 100% lit
Ward 12712.7, 100% lit
Ward 12815.6, 100% lit
Ward 12916.6, 100% lit
Ward 13027.2, 100% lit
Ward 13113.8, 100% lit
Ward 13234.8, 100% lit
Ward 13328.3, 100% lit
Ward 13422.0, 100% lit
Ward 13524.1, 100% lit

Listed by number, not ranked: night light shows where light is, not how people live. Each ward’s page sets it against its own past and its municipality.

Every municipality · Everything we hold for City of Johannesburg

Source

NASA Black Marble night lights, VNP46A3 (monthly) and VNP46A4 (yearly), collection 2, from NASA’s LAADS DAAC (doi:10.5067/VIIRS/VNP46A3.002 and doi:10.5067/VIIRS/VNP46A4.002). The product’s page.

What we changed: we added up NASA’s light over each 2026 ward (each pixel, about 460 m across, split in four and given to the ward holding each quarter) and added the wards up to municipalities, districts and provinces.

The satellite (Suomi NPP) passes at about 1:30 in the morning. NASA’s monthly figure is the mean of the month’s clear nights; a pixel with no clear night is filled from earlier months, and that share is shown. The yearly figure is NASA’s own mean of the year’s clear nights, so it is close to, not exactly, the mean of the twelve months.

Dataset: night light by ward, release 2026-11-13.