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Full catalog/MOD03
MOD03·v6.1·dataset

Pixel location helper file (Terra, 1 km)

MODIS/Terra Geolocation Fields 5-Min L1A Swath 1km
land NASA LAADS Level 1A active HDF-EOS
In plain English

What it measures. For each pixel a MODIS sensor sees, exactly where on Earth it falls (latitude, longitude, and ground height) plus the angles of the Sun and satellite and whether the spot is land or sea. It is essentially a precise map-location file for the imagery.

How it's made. Computed for the MODIS instrument on Terra using the spacecraft's position and orientation, instrument pointing, and a terrain elevation model.

How & where you'd use it. A behind-the-scenes building-block input feeding many other MODIS products; ordinary users almost never open it directly but rely on the geolocated products it enables.

What's measured

SPECTRAL/ENGINEERING › PLATFORM CHARACTERISTICS › ATTITUDE CHARACTERISTICSSPECTRAL/ENGINEERING › PLATFORM CHARACTERISTICS › ORBITAL CHARACTERISTICSSPECTRAL/ENGINEERING › PLATFORM CHARACTERISTICS › VIEWING GEOMETRY

Coverage & cadence

  • Time span2000-02-23 → ongoing
  • Measured byTerra (MODIS)
  • Processing levelLevel 1A
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS
  • 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 MODIS/Terra Geolocation Fields 5Min L1A Swath 1km are calculated for each 1 km MODIS Instantaneous Field of Views (IFOV) for all orbits daily (in Collection 6 and later, information is provided to claculate 500m geolocation fields). The locations and ancillary information corresponds to the intersection of the centers of each IFOV from 10 detectors in an ideal 1 km band on the Earth's surface. A digital terrain model is used to model the Earth's surface. The main inputs are the spacecraft attitude and orbit, the instrument telemetry and the digital elevation model. The geolocation fields include geodetic Latitude, Longitude, surface height above geoid, solar zenith and azimuth angles, satellite zenith and azimuth angles, and a land/sea mask for each 1 km sample. Additional information is included in the header to enable the calculation of the approximate location of the center of the detectors of any of the 36 MODIS bands. This product is used as input by a large number of subsequent MODIS products, particularly the products produced by the Land team. The short name for this product is MOD03. Each file is roughly 30 MB in size, and the total data volume is approximately 8 GB/day. See the MODIS Science Team homepage for more data set information: https://modis.gsfc.nasa.gov/data/dataprod/

Get the data

mod03_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MOD03",
    version="6.1",
    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.