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Full catalog/modis-aqua-myd09a1
modis-aqua-myd09a1·dataset

Clean 8-day global land imagery at 500m (Copernicus)

MODIS Aqua Surface Reflectance 8-Day L3 Global 500m
land ESA ESA Copernicus active
In plain English

What it measures. Provides true surface colour across seven light bands once the haze of the atmosphere has been stripped away, at 500-metre detail.

How it's made. Collected by the MODIS instrument on NASA's Aqua satellite and combined into 8-day, cloud-screened composites that keep the clearest view of each spot.

How & where you'd use it. A clean base layer for mapping land cover, vegetation, and surface change, and a starting point for many other environmental products.

What's measured

MODISAquaNASASatelliteGlobalImageryOpticalReflectanceSurface Reflectance500mMYD09A1

Coverage & cadence

  • Time span2002-07-04 → 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 Aqua MYD09A1 Version 6.1 product provides atmospherically corrected Surface Reflectance for MODIS Bands 1-7 at 500 m spatial resolution. The data are corrected for atmospheric effects including gases, aerosols, and Rayleigh scattering. The product is generated as an 8-day composite, where for each pixel the best observation is selected from all acquisitions within the compositing period based on criteria such as cloud conditions and solar zenith angle. When multiple observations meet these criteria, the pixel with the lowest value in Band 3 (blue) is selected. The product also includes a quality assurance layer and four observation bands to support data reliability and interpretation.

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-aqua-myd09a1"],   # 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.