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Full catalog/VNP46A1_NRT
VNP46A1_NRT·v2·dataset

Nighttime lights, near real-time (VIIRS, Suomi-NPP, daily)

VIIRS/NPP Daily Gridded Day Night Band 15 arc-second Linear Lat Lon Grid Night NRT V2
land NASA LANCEMODIS Level 3 active HDF5
In plain English

What it measures. Daily near real-time measurements of how much light the sensor recorded at night, plus many supporting layers like cloud flags, viewing angles, brightness temperatures, and moon illumination.

How it's made. Produced from the VIIRS Day-Night Band on the Suomi-NPP satellite as a raw, at-sensor nighttime radiance product gridded daily, delivered quickly for time-sensitive use.

How & where you'd use it. A foundational input for mapping nighttime lights, which others use to study electricity use, urban growth, fires, and power outages. It is typically used through cleaner higher-level products.

What's measured

SPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span2023-10-10 → ongoing
  • Measured bySuomi-NPP (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 first of two Visible Infrared Imager Radiometer Suite (VIIRS) Day Night Band (DNB) based Near Real Time (NRT) datasets is a daily, top-of-atmosphere, at-sensor nighttime radiance product called VIIRS/NPP Daily Gridded Day Night Band 15 arc-second Linear Lat Lon Grid Night. Known by its short-name, VNP46A1_NRT, this 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.

Get the data

vnp46a1_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VNP46A1_NRT",
    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 LANCEMODIS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.