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Full catalog/VJ203DNB
VJ203DNB·v2.1·dataset

Nighttime lights pixel locations, a helper file (VIIRS NOAA-21)

VIIRS/JPSS2 Day/Night Band Moderate Resolution Terrain-Corrected Geolocation 6-Min L1 Swath 750m V2.1
land NASA LAADS Level 1A active netCDF-4
In plain English

What it measures. A helper file that pins down exactly where each nighttime-light pixel sits on Earth, listing latitude, longitude, surface height, and sun, moon, and sensor angles.

How it's made. The terrain-corrected geolocation product for the VIIRS Day/Night Band on NOAA-21, computed from the satellite's position and an Earth terrain model.

How & where you'd use it. Pairs with the matching light-measurement files so data can be placed accurately on a map; used together with the radiance product, not alone.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › REFLECTED INFRAREDSPECTRAL/ENGINEERING › SENSOR CHARACTERISTICS › GEOLOCATIONSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span2023-02-10 → ongoing
  • Measured byNOAA-21 (VIIRS)
  • Processing levelLevel 1A
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • 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 VIIRS/JPSS2 Day/Night Band Resolution Terrain Corrected Geolocation 6-Min L1 Swath 750 m, short-name VJ203DNB product is the Joint Polar-orbiting Satellite System-2 (JPSS-2/NOAA-21) platform-based NASA Visible Infrared Imaging Radiometer Suite (VIIRS) L1 terrain-corrected geolocation product, and contains the derived line-of-sight (LOS) vectors for the single panchromatic Day-Night band (DNB). The geolocation algorithm uses a number of inputs that include an Earth ellipsoid, geoid, and a digital terrain model along with the SNPP platform’s ephemeris and attitude data, and knowledge of the VIIRS sensor and satellite geometry. It provides geodetic coordinates (latitude and longitude), and related parameters for each VIIRS L1 pixel. The VJ203DNB product includes geodetic latitude, longitude, surface height above the geoid, solar zenith and azimuth angles, lunar zenith and azimuth angles, sensor zenith and azimuth angles, land/water mask, moon illumination fraction and phase angle, and quality flag for every pixel location. The J2 VIIRS geolocation underwent an on-orbit validation. Geolocation errors of about 350 m in the along-scan direction and about 165 m in the along-track direction were corrected for the image-resolution bands and moderate-resolution bands. The Day-Night band (DNB) geolocation error of about 2000 m was corrected.

Get the data

vj203dnb_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ203DNB",
    version="2.1",
    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.