South African users of satellite imagery will gain significant benefits from the latest generation of SPOT earth observation satellites, SPOT 6 and SPOT 7. These form a small constellation, being deployed 180° apart in the same orbit. They replace a single satellite, SPOT 5, which was decommissioned at the end of March. This was highlighted recently by the South African National Space Agency (SANSA), which distributes SPOT imagery in South Africa. The agreement to do so was signed in 2006 by a SANSA predecessor agency, the Satellite Applications Centre (which was a unit of the Council for Scientific and Industrial Research).

“We’re celebrating nine years of SPOT data distribution. But we are bidding farewell to SPOT 5 and we are introducing SPOT 6 and SPOT 7,” affirmed SANSA Data, Products and Services Manager Aubrey Kekana. He was briefing South African imagery users in Pretoria. “We are able to create new products and services, given the new capabilities of SPOT 6.”

Just as SPOT 5 was a significant improvement over its predecessors, SPOT 6 and 7 provide a further jump in capability. Thus, whereas SPOT 5 had a resolution of 2.5 m for both multispectral and colour imagery, SPOT 6 and 7 have a resolution of 1.5 m for panchromatic and natural colour imagery. Yet, SPOT 6 and 7 have the same swath size as SPOT 5: 60 km by 60 km.

Other improvements include the ability (because there are now two satellites working together) to handle urgent tasking requests, which is very beneficial for disaster management and the ability to acquire six-million square kilometres of imagery every day (this is an area larger than that of the entire European Union). Any point on the earth can be revisited every day. Furthermore, four weather forecasts a day are automatically integrated with the satellite tasking process, with the result that 60% of the images have less than 10% cloud cover. This increases operational efficiency.

SANSA is, Kekana also reported, moving away from using DVDs and CD-ROMs to distribute the data it receives from earth observation satellites, because these are no longer efficient. Instead, the agency is moving to electronic distribution, online. He cited web mapping services as the future for all SANSA earth observation products and services. This will, however, be a phased process.

“We have disseminated SPOT data to over 50 organs of State and national, provincial and local government departments as well as research and academic institutions,” he stated. “This addresses a number of societal areas, such as agriculture, biodiversity, conservation, forestry, geology, land cover change, regional planning, national census, change detection studies and so on. This list goes on and on.”
Kekana also pointed out that SANSA sought not only to distribute data from earth observation satellites, but also to, as much as possible, train the recipients of that data so that they could use it properly. “At SANSA, our human capital development is not in competition or replacing any training system in the country,” assured SANSA research and applications development senior scientist Dr Clement Adjorlolo. The agency’s training activities include internships, short courses, university teaching, science fairs, specialised workshops and conferences and staff exchanges.

Internships are for post- graduate students (honours and master’s) and last for 12 months. The short courses range from one to five days each and are subsidised training. They are run by SANSA staff and/or invited lecturers. “We need to do more and more of these short courses,” he reported, due to the demand. “They are hands-on training for people working on [satellite] data, so that they can extract information from the data sets.” University teaching involves courses presented at universities across the country, showing how satellite data can be used by various disciplines. “Earth observation, GEOSS [Global Earth Observation System of Systems] is supposed to be simple, accessible to everyone,” noted Adjorlolo. The purpose of all these courses and programmes is to actually make it so.

SANSA also recently launched the national mosaics (covering South Africa) which it has compiled from images from SPOT 5 (taken last year) and SPOT 6 (taken in 2013). With SPOT 6 and 7 now both available, it will be possible to compile seasonal mosaics instead of just annual ones. The SPOT satellites are built and operated by Airbus Defence and Space (previously EADS Astrium). SPOT 5 was launched in 2002, SPOT 6 in 2012 and SPOT 7 in 2014.