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Full catalog/modis-terra-mod09q1
modis-terra-mod09q1·dataset

Sharpest clear-sky ground colors, 8-day, 250 m (Terra)

MODIS Terra Surface Reflectance 8-Day L3 Global 250m
land ESA ESA Copernicus active
In plain English

What it measures. It captures reflected sunlight in two bands (red and near-infrared) with atmospheric haze and scattering removed, at a finer 250-meter resolution. Each pixel is the best, clearest view chosen from an 8-day stretch.

How it's made. Made by ESA Copernicus from NASA's MODIS sensor on Terra, atmospherically corrected and composited as a Level-3 product.

How & where you'd use it. A core input for sharper vegetation mapping and land monitoring. Because it carries only two bands, it is best treated as a raw ingredient for other analyses rather than a standalone picture.

What's measured

MODISTerraNASASatelliteGlobalImageryOpticalReflectanceSurface Reflectance250mMOD09Q1

Coverage & cadence

  • Time span2000-02-18 → ongoing
  • Spatial extent-180, -90, 180, 90

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 MOD09Q1 Version 6.1 product provides atmospherically corrected Surface Reflectance for MODIS Bands 1 and 2 at 250 m spatial resolution. The reflectance values are corrected for atmospheric effects including gases, aerosols, and Rayleigh scattering. The dataset is generated as an 8-day composite, where for each pixel the most suitable observation is selected from all acquisitions within the compositing period based on criteria such as cloud conditions and solar zenith angle. When multiple observations satisfy these criteria, the pixel with the lowest value in Band 3 (blue) is selected. The product also includes two quality assurance layers that provide information about data quality and observation conditions.

Get the data

copernicus_access.py
# ESA Copernicus Data Space — open STAC API (free account)
from pystac_client import Client

cat = Client.open("https://stac.dataspace.copernicus.eu/v1")
search = cat.search(
    collections=["modis-terra-mod09q1"],   # add _cog or _nc for a format variant
    bbox=(-10, 35, 30, 60),             # your area (W,S,E,N)
    datetime="2024-01-01/2024-12-31",
)
items = list(search.items())            # then read assets with rioxarray / xarray
Browsing the Copernicus STAC is open; downloading bytes needs a free Copernicus Data Space account.