Sentinel-1 is a radar imaging satellite mission for land and ocean services, specifically designed to cover a wide range of environmental and security tasks. Weighing roughly 2.2 metric tonnes, the sentinel-1 satellites will orbit the Earth at an altitude of 700 km for at least seven years. The first satellite, Sentinel-1A, is scheduled for launch in 2013, to be followed in 2014 by the second satellite, Sentinel-1B.
The Astrium-built C-band SAR (Synthetic Aperture Radar) instrument is the core element of the mission. The C-band radar beam, with a wavelength of six centimetres, penetrates forests and scrub to reach the ground, and registers any movements or changes on the Earth’s surface to within a centimetre. The radar instrument can operate in four different observation modes enabling Sentinel-1 to respond to a wide range of varying requirements.
Sentinel-2 is the programme’s optical imaging mission, which likewise consists of two satellites. Astrium is the prime contractor for this mission.
Sentinel-2A, a satellite weighing 1.1 metric tonnes, is scheduled for launch in 2013, followed by Sentinel-2B in 2015. The two satellites will be placed in a polar orbit at an average altitude of 780 km above the Earth.
The Sentinel-2 mission is tailored towards the needs of operational land monitoring and emergency services. Sentinel-2 features a 290km-wide coverage, 10-20m spatial resolution, a 13 optical channel instrument (operating from visible-near infrared to shortwave infrared) and will ensure enhanced-quality continuity with existing Spot and Landsat missions. It will provide improved revisit time, swath width, coverage area, spectral bands, calibration and image quality. Astrium Germany is the satellite and platform prime contractor and Astrium France is responsible for the payload instrument and system support activities.
The Sentinel-3 satellite is designed to deliver infrared radiometry, i.e. high-precision temperature readings, altimetry (altitude measurements) via radar, and multi-spectral images with a ground resolution of 500–1,000m. It will be used for global monitoring of oceans and land areas. The first Sentinel-3 satellite is scheduled for launch in 2013. Astrium will deliver important, flight-proven equipment for this satellite. Astrium Spain has already been selected to prime the microwave radiometer. Thales Alenia Space is prime contractor for the satellite.
