The small satellite manufacturing subsidiary of Airbus Defence and Space, Surrey Satellite Technology Ltd (SSTL), celebrated the successful launch of two satellites, NovaSAR-1, a Synthetic Aperture Radar (SAR) satellite able to image the earth at night or through clouds, and SSTL S1-4, a high resolution optical Earth Observation satellite with a sub-one metre resolution. The two satellites were launched into a 580 km sun-synchronous orbit on board the PSLV launch vehicle from the Satish Dhawan Space Centre in Sriharikota, India on 16 September at 1637 GMT. The launch was provided by Antrix Corporation Limited, which is the commercial arm of the Indian Space Research Organisation.

PSLV on flight C42 launches SSTL-built satellites NovaSAR-1 and S1.4. Courtesy: ISRO


NovaSAR-1 is the first SAR spacecraft to be manufactured entirely in the UK and is a technology demonstration mission designed to test the capabilities of a new low cost S-Band SAR platform. NovaSAR-1 will be the world’s first commercial SAR satellite to be operated at a 1030 equatorial crossing time, providing time diversity for radar observations by affording increased daylight imaging opportunities in addition to night acquisitions. Mission partners signed up for capacity from NovaSAR-1 include the UK Space Agency, Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO), and the Indian Space Research Organisation (ISRO).

The UK Space Agency has invested GBP£21million in the development of NovaSAR-1 and will benefit from access to data from the spacecraft, significantly boosting the UK’s sovereign Earth observation capabilities and leveraging additional inward investment to the UK by creating highly skilled jobs in the UK space industry, and stimulating the growth of data analysis services.

NovaSAR-1 was designed and manufactured by SSTL, with an S-Band SAR payload developed by Airbus Defence and Space in Portsmouth. The spacecraft is also carrying an Automatic Identification System (AIS) Receiver supplied by Honeywell Aerospace. The SAR payload has a dedicated maritime mode designed with a very wide swath width of 400 km to enable the monitoring of the marine environment, and will provide direct radar ship detection information simultaneously with AIS ship tracking data to assist with the identification and tracking of sea-going vessels.

In addition to operating in maritime mode, NovaSAR-1 has been optimised with three additional imaging modes, including a six metre resolution imaging mode, for a range of other applications, such as flood monitoring and agricultural and forestry applications. The satellite has been designed to offer a high throughput of data, observing in a variety of polarisation combinations to additional information to acquisitions in the form of ‘colour’.

SSTL S1-4 satellite is a sub one metre Earth observation satellite identical in design to the three DMC3/TripleSat Constellation satellites launched in 2015. A contract to provide data from SSTL S1-4 was signed with China’s Twenty First Century Aerospace Technology Co., Ltd (21AT) in February 2018. As manufacturer and owner of the satellite, SSTL will lease imaging capacity to 21AT for the lifetime of the satellite, designed to be in excess of 7 years. SSTL S1-4 will contribute sub one metre resolution image data into 21AT’s existing TripleSat Constellation service, comprising three SSTL DMC3 satellites launched in 2015. SSTL S1-4 is capable of acquiring multiple targets in one pass, utilising spot, strip and mosaic imaging modes and 45 degree off-pointing agility for a range of applications including urban planning, agricultural monitoring, land classification, natural resource management and disaster monitoring. The very high resolution imager on-board the spacecraft has been designed and manufactured by SSTL and will acquire sub one metre resolution images in panchromatic mode and sub four metre resolution images in multispectral mode, with a swath width of about 24 km.

The systems on board both satellites are being commissioned in orbit from SSTL’s Spacecraft Operations Centre in Guildford UK.