African Association of
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Eye in the sky to monitor SA’s oceans

06 Jun 2016 11:53 AM | AARSE Admin (Administrator)
Source: BDLive

IN SOUTH African waters, beyond the sight of land or any other vessel, a ship’s smoke plume rises into the atmosphere. Its heat signature is written on the surrounding air, and overhead — less than 2,000km away — a tiny satellite is watching it. It is 2019, and the country’s oceans are monitored by a constellation of nanosatellites transmitting live data back to Earth.

SA’s ocean territory is larger than its land space, and if its claim to extend it is successful, its ocean geography will double.

This is why the government, as part of Operation Phakisa, is turning to satellites. Operation Phakisa aimed to boost the country’s ocean revenue to R177bn by 2033, from R54bn in 2010, President Jacob Zuma said at the operation’s launch in 2014.

"Nanosatellites were written into Phakisa’s founding documents," says Robert van Zyl, director of satellite engineering systems at the Cape Peninsula University of Technology (CPUT). CPUT houses the French South African Institute of Technology’s CubeSat programme.

"(CPUT) have been mandated by the Department of Science and Technology to develop ship-tracking services on a nanosatellite constellation, MDASat."

Short for marine domain aware satellites, MDASat will be a constellation of nine CubeSats.

CubeSats, a type of nanosatellite, are a burgeoning area of satellite-manufacturing. They are cube-shaped satellites small enough to fit into a person’s palm.

At about 10cm, they weigh no more than 1.3kg. Up to six of these cubes can be stacked together with different payloads, such as sensors or cameras, on them.

They are substantially cheaper than larger satellites, which run into millions of dollars.

"A CubeSat can be built for about $100,000 and launched for much the same, depending on the complexity of the mission," Van Zyl says. "For this reason, CubeSats were initially used to train students for the aerospace industry, but now these small spacecraft can be used to track and trace aircraft and vessels at sea."

SA already has one CubeSat in orbit, ZA-Cube1 — otherwise known as TshepisoSAT. This CubeSat, which is still operational, was launched by CPUT in 2013. It has a high-frequency beacon that can beam messages from space.

ZA-Cube2, however, will be expected to do much more.

As the precursor to the constellation, it will be fitted with receivers to pick up signals from ships in the ocean, and transmit information back to Earth.

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BIG vessels are fitted with automatic-identification service (AIS) beacons that transmit tracking and identity information to nearby vessels and authorities.

"We have to make (the AIS detector) small enough to fit on a CubeSat," Van Zyl says.

CPUT is teaming up with technology company Three Stone in Somerset West that is responsible for developing the firmware.

"ZA-Cube2 will also have a powerful (optical) camera on it and a near infrared camera — we want to see if we can distinguish fire or, ideally, the heat plume of a ship," Van Zyl says.

It will also be able to detect AIS beacons. "That way, if you see a ship with no AIS beacon, (you know that) there might be a problem. This data is important in addressing piracy and illegal fishing."

The department’s chief director of space science and technology, Humbulani Mudau, says the constellation — expected to be in the sky by 2019 — will initially focus on "all South African terrestrial and maritime territories, including the exclusive economic zone and the continental shelf".

SA’s exclusive economic zone extends about 200 nautical miles from its coastline. This is an area in which SA has the sovereign right to use the ocean’s resources — for energy, mining, or fishing.

The use of satellites could identify fishing areas, ensure the safety of shipping vessels, and do real-time monitoring of oil spills, Mudau says. Concerns around oil spillages were highlighted in a Department of Environmental Affairs presentation to Parliament in April last year.

"We are located along a very busy shipping route with harsh ocean conditions," says deputy director-general for oceans and coasts Monde Mayekiso.

This means the area is vulnerable to oil spill incidents from ships, with more than 20 serious marine pollution incidents reported since 1994.

Mudau says the constellation would allow for rapid response to problems in SA’s oceans, "which is a critical requirement for law enforcement and first-responder rescue operations".

The project has been allocated R98m over five years, which will cover the satellites’ manufacture, launch, operations, and commercialisation, Mudau says.

The government — through the departments of science and technology, and trade and industry — has been pushing satellite manufacturing for more than a decade, but industry has not been kind to the high-technology niche.

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SATELLITE company SunSpace, established by a group of Stellenbosch University alumni and responsible for democratic SA’s first home-grown satellite, Sumbandila, failed to attract the contracts that would sustain it, and died a protracted death before it was absorbed into state-owned Denel Dynamics in 2013.

But CubeSats appear to be a low-risk way into satellite manufacturing, with both CPUT and Stellenbosch University developing capacity.

Herman Steyn was part of SunSpace and now heads Stellenbosch University’s satellite engineering unit.

"After Sumbandila, there were no funds to do the space project…. In the meantime, I don’t want to do nothing. CubeSats are not expensive," he says.

"We have good engineers in SA, so I thought, ‘Let’s continue with CubeSats’."

Stellenbosch University is part of QB50, a European Commission project that will see the construction, launch, and destruction of 50 CubeSats.

The project aims to increase countries’ access to space.

Stellenbosch University’s spin-out company, CubeSpace, will be building the control system for these nanosatellites.

"Up until now, most CubeSats have been uncontrolled, randomly tumbling in orbit. It is difficult to position your antennas to the ground station, your solar panels to the sun, your camera to Earth," Steyn says.

"There are not many companies — fortunately for us — that supply control systems for CubeSats."

SA will be contributing one CubeSat, called ZA-AeroSat, to the QB50 mission.

Steyn’s unit is collaborating with CPUT on the MDASat constellation, by providing the control systems.

In turn, CPUT will supply Stellenbosch University with transmitter and transceiver modules that will allow its CubeSats to receive and transmit signals.

Mudau says space technologies have a vital role to play in SA, such as in telecommunications, Earth observation and space sciences.

And importantly, for a developing country with a high technology skills shortage, they are a relatively cheap way to train postgraduates in space engineering.

The MDASat project is expected to see 60 masters’ degree graduates trained and ready to enter SA’s small space industry.


Original article


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