Space-Based Sensors Track Air Quality

A recently launched European Space Agency (ESA) mission, Sentinel-4, will monitor air quality using image sensors designed and manufactured by **Teledyne Space Imaging**. These sensors will provide crucial data on trace gases over Europe.

Sentinel-4 Mission Objectives

Mounted on the Meteosat Third Generation Sounder (MTG-S) satellite, Sentinel-4 is part of the European Union’s Copernicus programme, a collaborative effort led by the European Commission (EC) and ESA. The satellite launched successfully on July 1 from Cape Canaveral, Florida.

The mission’s primary goal is to gather hourly data on tropospheric constituents over Europe, which will then be used for air quality applications and monitoring initiatives. This data offers essential insights into climate trends, air pollutants, and ozone/surface ultraviolet (UV) radiation.

Teledyne’s Detector Technology

This launch marks the second in a week featuring detector technology from **Teledyne Space Imaging**. On June 28, 2025, the Japanese Global Observing SATellite for Greenhouse gases and Water cycle (GOSAT-GW) mission launched with two CIS120 sensors from Teledyne.

Sensor Details

Sentinel-4 uses two types of CCD sensors within its Ultraviolet-Visible-Near-Infrared (UVN) imaging spectrometer. The CCD374 sensor captures images at ultraviolet and visible wavelengths, while the CCD376 sensor operates in the near-infrared range. From its geostationary orbit, the mission will monitor trace gases, including ozone, nitrogen dioxide, and sulphur dioxide. According to the World Health Organization, 99% of the global population breathes air that exceeds air quality limits, posing a significant threat to health (WHO, 2022).

Project Development Timeline

**Teledyne Space Imaging**’s involvement in the Sentinel-4 project began in 2009 during the initial development phase. This phase included detector design, prototype manufacturing, and radiation testing. A second phase, starting in 2012, focused on designing and validating the flight detectors, incorporating updates from the first phase. The flight model phase, completed in 2019, involved manufacturing the flight deliverables.

Reliability testing was conducted to ensure the detectors would last beyond the mission’s expected 10-year lifespan.

Expert Perspectives

“Our sensors were selected due to the heritage of our work on Sentinel-2 and -3, as well as internal developments that met the needs of this mission,” said **Ross Mackie**, Principal Project Lead Engineer at **Teledyne Space Imaging**. He further added, “Our detectors fulfilled all the mission’s requirements for operation in various wavelengths, giving us the edge in developing these exciting products for Sentinel-4. We were able to offer a bespoke approach to provide the best possible results for the mission.”

**Tracy Phillips**, **Teledyne’s** Principal Project Manager, shared her experience: “Managing the CCDs for the Sentinel-4 mission was one of my first projects at Teledyne, and it was fascinating to learn about the technological capabilities of our detectors. It’s very exciting to work with such advanced sensors that will contribute to gathering vital information about our planet, ultimately better protecting Earth and helping save lives.”