Sentinel-1 is a two satellite constellation with the prime objectives of Land and Ocean monitoring. The goal of the mission is to provide C-Band SAR data continuity following the retirement of ERS-2 and the end of the Envisat mission.

To accomplish this the satellites carry a C-SAR sensor, which offers medium and high resolution imaging in all weather conditiions. The C-SAR is capable of obtaining night imagery and detecting small movement on the ground, which makes it useful for land and sea monitoring.

Launch Dates:

Sentinel-1A - 03 April 2014
Sentinel-1B - 25 April 2016
Operational lifespan: 7 years (With consumables for 12)

Mission Objectives:

• Land monitoring of forests, water, soil and agriculture
• Emergency mapping support in the event of natural disasters
• Marine monitoring of the maritime environment
• Sea ice observations and iceberg monitoring
• Production of high resolution ice charts
• Forecasting ice conditions at sea
• Mapping oil spills
• Sea vessel detection
• Climate change monitoring

Mission Orbit:

• Orbit Type: Sun-synchronous, near-polar, circular
• Orbit Height: 693 km
• Inclination: 98.18°
• Repeat Cycle: 175 orbits in 12 days

Payload:
C-SAR (C-band Synthetic Aperture Radar)

Resolution and Swath Width (Four modes):

• Strip Map Mode: 80 km Swath, 5 x 5 m spatial resolution
• Interferometric Wide Swath: 250 km Swath, 5x20 m spatial resolution
• Extra-Wide Swath Mode: 400 km Swath, 25 x 100 m spatial resolution
• Wave-Mode: 20 km x 20 km, 5 x 20 m spatial resolution

Configuration:
With the single C-SAR payload, the spacecraft carries a deployable solar array, and large data storage. The mission is expected to provide data quickly, in the event of disaster monitoring, and will utilise an X-band downlink to accomplish this.
The dimensions of the craft are: 3.9 x 2.6 x 2.5 m with a weight (at time of launch) of 2300 KG.

Launch Vehicle:
Soyuz rocket

Ad interim Operator:
ESA

Data Processing:

• Level-0 Compressed and unprocessed instrument source packets
• Level-1 Ground Range Detected Geo-referenced Products
• Level-2 Ocean products

Contractors:
The prime contractor for the construction and integration of the satellites is Thales Alenia Space.
Astrium is responsible for the construction of the C-SAR payload.
DLR is responsible for the Laser Communication Terminal (LCT), which will quickly transmit data to the European Data Relay Satellite (EDRS) that is intended to aid in the fast transmission of data for the Sentinel-1 and 2 missions by using an optical laser link to transmit data back to the ground facility.
Arianespace is contracted to launch the spacecraft