Planetary-scale answers, unlocked.
A Hands-On Guide for Working with Large-Scale Spatial Data. Learn more.
Authors
Sentinel-2 is the European Copernicus satellite mission that images Earth's land and coastal waters in 13 spectral bands, from visible light to shortwave infrared, at 10, 20, and 60 m resolution. Each satellite carries the optical MultiSpectral Instrument (MSI) and covers a 290 km swath, and two satellites in the same orbit revisit every location every five days at the Equator. The data is free, and Copernicus services apply it to agriculture, forestry, land cover, and disaster mapping.
Sentinel-2 is ready to query in the Havasu catalog: the Sentinel-2 L2A scene index and RasterFlow's cloud-filtered Sentinel-2 mosaics.
Sentinel-2 is part of Copernicus, the European Union's Earth observation program, and the European Space Agency (ESA) builds and operates the satellites. ESA's Sentinel-2 mission page on SentiWiki describes it as "a European wide-swath, high-resolution, multi-spectral imaging mission" designed for a revisit of five days at the Equator.
Each satellite flies a sun-synchronous orbit at 786 km and crosses the Equator at 10:30 am local time, close to the Landsat overpass. The MSI is a passive push-broom sensor: it collects reflected sunlight row by row across the swath as the satellite moves forward.
Sentinel-2A launched in 2015, Sentinel-2B in 2017, and Sentinel-2C on 5 September 2024, all on Vega rockets. According to SentiWiki, Sentinel-2C replaced Sentinel-2A in operations on 21 January 2025, so the nominal pair is now Sentinel-2B and Sentinel-2C. Since March 2025, Sentinel-2A has flown an extension campaign 36° from Sentinel-2B. Sentinel-2D will succeed Sentinel-2B. Systematic coverage spans all land between 56° South and 82.8° North and coastal waters up to 20 km from shore.
Sentinel-2 bands run from B1 to B12, plus a narrow near-infrared band, B8A. Wavelengths and resolutions below come from the Microsoft Planetary Computer Sentinel-2 Level-2A collection STAC metadata; B10, absent from Level-2A, comes from SentiWiki.
SentiWiki describes the two 20 m SWIR bands as serving "snow/ice/cloud detection, or vegetation moisture stress assessment," and the 60 m bands as serving cloud screening and atmospheric correction. Its per-satellite wavelengths differ from the nominal STAC values by a few nanometers; B8 is 832.8 nm on Sentinel-2A. For hundreds of narrower bands, see hyperspectral imagery.
SentiWiki defines four kinds of Sentinel-2 resolution.
Three satellites are now in orbit. The five-day figure applies to the nominal Sentinel-2B and Sentinel-2C pair, and the Sentinel-2A extension campaign adds revisits over Europe and cloudy tropical Africa and South America.
ESA processes every acquisition to Level-2A and releases two levels to users, described on SentiWiki's Sentinel-2 products page.
The SCL is a 20 m map with 12 classes. SentiWiki's processing page lists them: 0 no data, 1 saturated or defective, 2 cast shadows, 3 cloud shadows, 4 vegetation, 5 not vegetated, 6 water, 7 unclassified, 8 cloud medium probability, 9 cloud high probability, 10 thin cirrus, and 11 snow or ice. A mask for clear land and water keeps classes 4, 5, and 6 and sets every other class to no data.
Two details affect every time series. From processing baseline 04.00 on 25 January 2022, values carry a band-dependent offset, so reflectance is (digital number + offset) / quantification value, with both numbers in the product metadata. ESA also reprocessed the archive from 2015 to 13 December 2023 as Collection-1 with uniform baselines and removed the older Collection-0 products from the Copernicus Data Space Ecosystem.
The EU legal notice on Copernicus Sentinel data grants users "free, full and open access" for reproduction, distribution, and modification, with a credit line of "Copernicus Sentinel data [Year]".
Older tutorials point to the Copernicus Open Access Hub (SciHub) for Sentinel-2 download. SentiWiki now names the Copernicus Data Space Ecosystem as "the main distribution service for data from the Copernicus Sentinels missions." Four sources cover most work:
SentiWiki's Sentinel-2 applications page lists the common composites:
The same page lists the common indices: NDVI as (B8 – B4) / (B8 + B4), the moisture index NDMI as (B8A – B11) / (B8A + B11), NDWI as (B3 – B8) / (B3 + B8), and NDSI as (B3 – B11) / (B3 + B11).
Sentinel-1 is the Copernicus radar mission, covered in depth in the synthetic aperture radar guide. The Sentinel-1 mission overview gives its C-band radar, 250 km Interferometric Wide swath at 5 m by 20 m, and 12-day repeat cycle per satellite.
Analysts use Sentinel-2 to separate vegetation, water, and materials by color, and Sentinel-1 to cover cloudy dates. Both are core Earth observation data sources, and SentiWiki notes that Sentinel-2 is well suited to validating sea ice conditions extracted from Sentinel-1.
Landsat and Sentinel-2 are both free, global optical archives. Landsat 8 and 9 have 30 m pixels and a 16-day repeat. Sentinel-2 has 10 to 20 m pixels and a five-day repeat, per the Harmonized Landsat and Sentinel-2 (HLS) project. Sentinel-2's 290 km swath is wider than the 185 km of Landsat 5 and 7, and its 10:30 am overpass sits close to Landsat's.
NASA's HLS combines the two into one analysis-ready surface reflectance record at 30 m. It publishes an L30 product from Landsat 8 and 9 and an S30 product from Sentinel-2A, 2B, and 2C, covering all land except Antarctica with a global observation frequency of 2 to 3 days. ESA's Sen2Like tool harmonizes Sentinel-2 and Landsat for users who process their own scenes.
WherobotsDB reads Sentinel-2 Cloud Optimized GeoTIFFs where they sit in cloud storage and runs raster and vector operations on them in SQL. The Sentinel-2 L2A scene index in Wherobots open data holds one row per scene, with footprint, acquisition time, cloud cover, MGRS tile, processing baseline, and links to every band COG. The STAC reader loads scenes from other STAC catalogs. Bands load as out-db rasters, read only in the tiles a query touches, an approach explained in raster processing at scale with the out-of-database architecture. RS_MapAlgebra computes indices and SCL masks, and RS_ZonalStats summarizes them per polygon, which joins raster and vector data in one query.
In the Strait of Hormuz vessel analysis, "WherobotsDB read 719 Sentinel-2 scenes, 151 GB in total, straight from the public archive and fetched only about 1.5 GB covering three areas of interest."
RasterFlow builds the cloud-filtered Sentinel-2 mosaics and the Fields of the World field boundaries derived from them, as the Fields of the World pipeline post describes. Wherobots used the same zonal statistics pattern to compute mean embeddings for about 3.5 million Iowa fields across 2023-2025.
The models people use every day were trained on text, documents, databases, and the internet, and none of those sources hold last week's Sentinel-2 scene. Through the Wherobots MCP Server, an AI agent can search the scene index and get a runnable query back. That is geospatial AI applied to Earth observation.
-- Find clear Sentinel-2 L2A scenes over an area of interest for summer 2025 -- wherobots_open_data.sentinel2.l2a_source_items: one row per L2A scene (STAC item) -- with footprint, acquisition time, cloud cover, and links to band COGs SELECT id, mgrs_tile, datetime, `eo:cloud_cover` AS cloud_cover, assets.red.href AS red_cog, assets.nir.href AS nir_cog, assets.scl.href AS scl_cog FROM wherobots_open_data.sentinel2.l2a_source_items WHERE year = 2025 AND month BETWEEN 6 AND 8 AND ST_Intersects(geometry, ST_GeomFromText('POLYGON((-93.8 41.5, -93.4 41.5, -93.4 41.8, -93.8 41.8, -93.8 41.5))')) AND `eo:cloud_cover` < 10 ORDER BY cloud_cover, datetime;
Search Sentinel-2 scenes and join them to fields and buildings in SQL with a Wherobots free trial at cloud.wherobots.com.
Sentinel-2 images Earth’s land surfaces, inland waters, and coastal waters in 13 spectral bands from visible to shortwave infrared, at 10, 20, and 60 m resolution, revisiting each location every five days at the Equator. Copernicus services use the imagery for land cover mapping, agriculture, forestry, water management, and emergency mapping of floods and wildfires.
Yes. EU law gives users free, full and open access to Copernicus Sentinel data, including reproduction, distribution, and modification. Anyone who publishes or redistributes the data must credit it as ‘Copernicus Sentinel data [Year]’, or ‘Contains modified Copernicus Sentinel data [Year]’ when the data has been changed.
Sentinel-1 and Sentinel-2 are two Copernicus satellite missions. Sentinel-1 carries a C-band synthetic aperture radar that images day or night through cloud. Sentinel-2 carries the MultiSpectral Instrument, a passive optical sensor that records reflected sunlight in 13 bands. Radar data covers cloudy and dark periods, and optical data adds color and vegetation detail.
Sentinel-2 and Sentinel-3 are separate Copernicus satellite families. Sentinel-2 is the high-resolution, wide-swath multispectral imaging mission for land and coastal monitoring, with pixels of 10 to 60 m. Sentinel-3, operated jointly by ESA and EUMETSAT, measures sea surface height, sea and land surface temperature, and ocean and land color for ocean forecasting and environmental monitoring. Its OLCI instrument images at 300 m, so Sentinel-3 trades detail for wide, frequent coverage. The Sentinel-3 mission overview lists its instruments.
Sentinel-2 has 13 spectral bands: four at 10 m (blue, green, red, and near-infrared), six at 20 m (four red edge and narrow near-infrared bands and two shortwave infrared bands), and three at 60 m (coastal aerosol, water vapour, and cirrus). Level-2A products drop the cirrus band B10, which carries no surface information.
Each Sentinel-2 satellite repeats its orbit every 10 days. Two satellites phased 180° apart give a revisit time of five days at the Equator. Since March 2025, an extension campaign for Sentinel-2A adds acquisitions over Europe and tropical Africa and South America.
The Copernicus Data Space Ecosystem is the main distribution service for Sentinel-2, with a browser and APIs. Cloud copies include the Sentinel-2 Cloud-Optimized GeoTIFFs on AWS, searchable through the Earth Search STAC API, the Sentinel-2 Level-2A collection on Microsoft Planetary Computer, and the harmonized surface reflectance collection in Google Earth Engine.
What is H3? Uber’s Hexagonal Spatial Index
H3 is Uber's open-source hexagonal grid for indexing locations on Earth. How the H3 index works, its 16 resolutions, H3 vs S2 and geohash, and H3 in SQL.
What is Geospatial Data? Types, Formats, Examples
Geospatial data describes things tied to a place on Earth. The two main types, vector and raster, plus formats, sources, and examples.
What is Geospatial Analysis? Methods and Examples
Geospatial analysis, or spatial analysis, examines where things are and how location shapes patterns. Methods, examples, GIS vs spatial analysis, and SQL.
share this article
Awesome that you’d like to share our articles. Where would you like to share it to:
