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Full catalog/VJ146A1
VJ146A1·v2·dataset

Nighttime lights (NOAA-20, daily, 15 arcsec)

VIIRS/JPSS1 Daily Gridded Day Night Band 15 arc-second Linear Lat Lon Grid Night
land NASA LAADS Level 3 active HDF5
In plain English

What it measures. Nighttime lights seen from space, measuring how much light Earth's surface gives off at night, plus a host of supporting layers like cloud flags, viewing angles, and moonlight conditions.

How it's made. Produced from the day-night band of the VIIRS instrument on the NOAA-20 satellite, gridded daily at fine resolution as a top-of-atmosphere radiance product, part of the Black Marble collection.

How & where you'd use it. Mapping human settlement, electricity use and economic activity, tracking power outages after disasters, and studying light pollution. This newer version covers both land and water surfaces.

What's measured

SPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span2018-01-05 → ongoing
  • Measured byNOAA-20 (VIIRS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF5
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The NOAA-20 VIIRS Daily Gridded Day Night Band 15 arc-second Linear Lat Lon Grid Night product, short-name VJ146A1 is a daily, top-of-atmosphere, at-sensor nighttime radiance product. This product is available at 15 arc-second spatial resolution from January 2018 onward. The VJ146A1 product contains 26 Science Data Sets (SDS) that include sensor radiance, zenith and azimuth angles (at-sensor, solar, and lunar), cloud-mask flags, time, shortwave IR radiance, brightness temperatures, VIIRS quality flags, moon phase angle, and moon illumination fraction. It also provides Quality Flag (QF) information specific to the cloud-mask, VIIRS moderate-resolution bands M10, M11, M12, M13, M15, M16, and DNB. The current v2.0 collection contains several changes and differences relative to the previous v1.0 collection. These include radiance data format change from unsigned integer to floating-point, from exclusively for land surfaces coverage to both land and water surfaces, updated Mandatory_Quality_Flag layer, and others. Consult the v2.0-specific Black Marble [User Guide](https://landweb.modaps.eosdis.nasa.gov/data/userguide/BlackMarbleUserGuide_Collection2.0_20241203.pdf) for additional details.

Get the data

vj146a1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ146A1",
    version="2",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from LAADS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.