# InfraRed Sounder (IRS)
*sensor . products*

Geostationary hyperspectral infrared sounder carried by MTG-S1 for temperature, humidity, wind-profile and atmospheric-constituent retrieval.

## Specifications
- **product status**: in-development
- **deployment context**: orbital
- **manufacturer**: esa
- **sensor**: {"instrument_family":"passive-optical","measurement_principle":"passive","spectral_range_nm":{"min":4440,"max":14700},"spectral_band_count":1960,"gsd_m":{"native":4000},"channels":[{"name":"MWIR","spectral_range_nm":{"min":4440,"max":6250}},{"name":"LWIR","spectral_range_nm":{"min":8260,"max":14700}}]}
- **entity type**: sensor
- **last verified date**: 2026-06-16
- **verified by**: agency-doc
- **claim status**: agency-sourced
- **provider**: esa
- **attributes**: {"kind":"sensor","product_status":"in-development","deployment_context":"orbital","manufacturer":"esa","description":"Geostationary hyperspectral infrared sounder carried by MTG-S1 for temperature, humidity, wind-profile and atmospheric-constituent retrieval.","sensor":"{\"instrument_family\":\"passive-optical\",\"measurement_principle\":\"passive\",\"spectral_range_nm\":{\"min\":4440,\"max\":14700},\"spectral_band_count\":1960,\"gsd_m\":{\"native\":4000},\"channels\":[{\"name\":\"MWIR\",\"spectral_range_nm\":{\"min\":4440,\"max\":6250}},{\"name\":\"LWIR\",\"spectral_range_nm\":{\"min\":8260,\"max\":14700}}]}"}

## Editorial
InfraRed Sounder (IRS) is ESA's passive optical hyperspectral infrared sounder for Meteosat Third Generation Sounder satellites, including MTG-S1.[^wmo-irs][^eumetsat-mtg-s1] The instrument is an imaging Fourier transform interferometer operating in two infrared channels: MWIR from 4440-6250 nm and LWIR from 8260-14700 nm.[^wmo-irs] Each dwell contains 1960 spectral channels, with ground sampling of 4.0 km at the sub-satellite point.[^wmo-irs] IRS scans the Earth disc through local-area-coverage latitude belts, with the Europe belt revisited every 30 minutes and the full-disc belt pattern completed over six hours.[^wmo-irs] Its role is atmospheric temperature, humidity, wind-profile and atmospheric-constituent sounding, not land imaging.[^wmo-irs][^eumetsat-mtg-s1] MTG-S1 launched on 2025-07-01, and IRS utilization spans 2026 to 2046 with planned flights on MTG-S1 and MTG-S2.[^wmo-irs][^eumetsat-mtg-s1] The instrument is capable of atmospheric sounding workflows and atmospheric-motion-vector derivation from its geostationary infrared observations.[^wmo-irs]

## Compositional position
- mtg-s1 (missions) --[mission_payloads]--> InfraRed Sounder (IRS)

## Sources
- [wmo-irs] | WMO OSCAR instrument record: InfraRed Sounder | https://space.oscar.wmo.int/instruments/view/irs | tier=community | accessed=2026-06-16
- [eumetsat-mtg-s1] | EUMETSAT MTG-S1 and Copernicus Sentinel-4 overview | https://www.eumetsat.int/meteosat-third-generation-sounder-1-and-copernicus-sentinel-4 | tier=agency-doc | accessed=2026-06-16

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Source: https://eo-atlas.org/products/sensor/irs
Maintainer: SpectraWorks B.V. (CC-BY 4.0)