Launching your own satellite — the pros and cons
Developing nations are building their own satellites despite freely available Western data. Do the gains outweigh the costs, asks Tatum Anderson.
India's aim to launch two more satellites in the next three years has highlighted the trend for developing countries to add their own presence to the West's already extensive space portfolio — sometimes at major cost to their finances.
The Indian Space Research Organisation (ISRO) announced plans last month (18 October) for two Earth observation satellites, which will join six already in orbit. South Africa launched its first commercial-grade satellite the previous month (17 September); Brazil, China, Thailand and Vietnam have satellites, as do Algeria and Nigeria.
Many of these satellites seek to monitor the environment, from population density to flooding to carbon emissions. But experts question whether this is the best use of precious funds, especially for countries that do not even manage to feed their people. With free satellite data now available from several international organisations in Europe and the United States, funding priorities are likely to receive even closer attention.
South Africa builds capacity
One example is South Africa's new satellite, SumbandilaSat, which will monitor the country's environment, from crops and population density to dam levels, with six high-resolution cameras. It should provide better disaster management — such as tracking floods that regularly blight surrounding countries, and domestic savannah fires — and could even track crop yields to better predict droughts.
But a key goal for South Africa is also national — and scientific — self-confidence, according to Herman Steyn, professor of electronic engineering at the University of Stellenbosch, where the satellite project began. As he says, it has helped train a new generation of African space scientists and engineers.
"If you want to stimulate Africans to take up science and engineering as a career you need to be able to tell them that we can also do it," Steyn says. "For every South African, it is exciting to see a satellite that has been built here."
Taking control of technology
And with the imminent launch of the South African National Space Agency, there is another issue at play — the need for control, explains Steyn.
"If someone else builds your satellite they have control of the technology — what they will allow you to use and what you get for your money," he says.
In Nigeria, national self-confidence is clearly an issue. In 2006 the government approved a 25 year space roadmap that aims to produce Nigerian astronauts and space flights, and has started building its own satellites.
Previous satellites were built by Surrey Satellite Technology in the United Kingdom, and Nigeria has for several years been sending engineers there to acquire skills. The country has now built two Earth observation satellites of its own — NigeriaSat-2 and NigeriaSat-3.
A third of the world's poor live in India. Are satellites the best use of resources?
But half of Nigeria's population lives below the poverty line and one child in every ten dies before the age of five. Similarly India, which has run a space programme since the 1980s, is home to one third of the world's poor and some of the worst tubercolosis and child malnutrition rates on the planet.
"I say: stop, think twice. Don't do it for your glory," says Henk Verschuur, a senior training officer at the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). "There are a lot of priorities in Africa where the money is needed more."
Michael Goodman, at NASA's Natural Disasters Program, agrees. "It is expensive to launch and maintain satellite operations and developing countries might be better served by building capacity to use and interpret satellite data."
Nigeria has defended its space ambition.
Professor Robert Boroffice, past director general of Nigeria's National Space Research & Development Agency, said in a paper last year: "Many in developing countries are very sceptical about investment in space, arguing that the money could be better spent on improving the human condition on Earth, forgetting that space offers a unique opportunity to balance consumption and production, and therefore ensure sustainability of our resources and environment."
"Each country should develop and pursue its own programme within the limits of national resources."
Is free data enough?
Some in India support Nigeria's position. Measures that help mitigate disasters — such as satellite imagery — are vital, says Sanjay Srivastava, a scientist at the Indian Space Research Organisation's disaster management support programme.
But such data is increasingly available for free from other sources. For example, EUMETSAT says its satellites take excellent images of Africa that are free to use, and the organisation also offers free training on how to use the data.
When China suffered the earthquake in southern Sichuan last year, 22 countries produced images of the affected area through the International Charter agreement, which compels them to send free data during large-scale humanitarian disasters.
Also available for free are data from the United States' many Earth observation satellites, via agencies such as the National Oceanic and Atmospheric Administration (NOAA) and NASA.
Meanwhile, the US Geographical Survey (USGS) has this year made its 30 year archive and some live images available for the first time — "a huge revolution and policy change. It is a wonderful move that is a real gift to the world," according to Woody Turner, a NASA scientist who specialises in using satellite data for ecological forecasting.
But the satellite pioneers in the developing world point out that just because a data source is free does not mean it is useful.
Data and predictions from international agencies can sometimes be quite vague.
"It is very difficult to act on crude information," says Srivastava. "It's great to know that El Niño may affect India but we need to know when and which part of India will be hit."
And this is a problem for all lower orbit satellites, regardless of who launched them, particularly those that orbit over the poles. They return to the same spot too infrequently for the needs of many countries, sometimes every five days, sometimes every 10 or 20 if the satellite cannot see through cloud cover.
Meteorological satellites, such as those belonging to EUMETSAT and NOAA, can collect data more frequently as they are geostationary and view a large fixed position. But they are so far away that images can lack detail.
Monsoon rains lash Cambodia and Vietnam
NASA/Goddard Space Flight Centre
Free images can also be old and if countries want a certain image it may well be outside the remit of free data access, so they have to pay for a satellite to take it. That can cost millions of South African rand a year, says Steyn.
Demand for more satellites
And because some satellites are in high demand — and not necessarily available for free, particularly those with very high resolution sensors — countries can be put on waiting lists and do not get the images they need even if there are no commercial constraints.
South Africa, for example, wants to monitor its coast for illegal fishing vessels on an almost daily basis, and check for drought by frequent monitoring of the health of crops.
Applications like these have led some experts to agree that more satellites should be deployed to provide sufficient information — and not just by developed countries — in addition to replacing those reaching the end of their lives.
"The more the better," says NASA's Turner. "Satellites will fail. You want something else up there looking at what you were looking at."
Microsatellites cut the cost
The debate is moving on now as advances in satellite technology are bringing costs down. A new generation of microsatellites has arrived and they are lighter and cheaper to launch and operate.
At present they cannot carry many of the special sensors that produce very high-resolution images or cover all parts of the electromagnetic spectrum. But they can produce useable optical and infrared data.
Microsatellites are now favoured by developing countries, with the notable exception of India. For instance, South Africa's SumbandilaSat weighs just 81 kg and cost 26 million South African rand (US$3.4 million). Microsatellites are mooted for the African Resource Management satellite constellation project, which aims to share and coordinate data on the continent.
"These are really very low-cost satellites and don't need a capability for geological applications," says Verschuur at EUMETSAT. "I think these low-cost satellites can be justified."
Data processing challenge
Building and launching a satellite is not the only cost. The work on the ground to understand and make use of the data can be formidable.
Some sources say government agencies cannot always use the data they receive, whether from their own satellites or from free sources, because they do not have sufficient processing capacity.
India has taken years to perfect its system — a particular hurdle has been convincing its own health, water and environmental agencies to accept and use the data, says Srivastava at the Indian Space Research Organisation.
There is, though, the free training on processing satellite data from EUMETSAT and also from the UN and NASA, whose SERVIR project is setting up groups of local analysts in Central America and East Africa and, soon, Nepal. Meanwhile an African Union Commission project, AMESD (African Monitoring of the Environment for Sustainable Development), aims to create networks for using Earth observation data, among other objectives.
Very few people have the knowledge to analyse satellite data
But Lawrence Aribo, an expert in drought monitoring at Uganda's ministry of water and environment, says many gaps exist. There is little computer data storage, so geographic information systems (GIS) experts in his country are often forced to delete older images to look at new ones. That means no comparisons can be made over time.
"The computers are so slow and cannot keep data for long," he says. "And you need skills in GIS but there are very few people who have the knowledge to analyse this data."
Capacity building is needed at ground level — as well as up in space.