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Satellites have put maritime communication development into overdriveIt was in the 1960s when the first space satellites began orbiting the earth and almost immediately the impact on global shipping was exceedingly positive. Maritime communications, which were mostly stagnant or very slow in development, exploded almost overnight.
Now, just over half a century after the Russians sent the first Sputnik into orbit, alarm bells went off when two fully intact man-made satellites, with a combined weight of just under 1 500 kilograms, collided at 790 kilometres above the surface of the earth.
In the early years of the 20th century, the invention of radio helped to transform communications at sea fairly substantially. Other new modern communication technologies like the telegraph and telephone were of little use to shipping because these required fixed cables and lines to carry sound-based communication.
In this regard, radio represented a quantum shift with sound travelling across the ether. This technological breakthrough was quickly adapted for use at sea.
Morse code was first used to send maritime distress signals at the end of the 19th century and was still mainly in use by the second half of the 20th century.
Maritime radio at the time used medium wave, which had about a 320km range. It used Morse code because it could not transmit human voice and high frequency for voice, which could only be transmitted over distances of up to 40km.
The result was that a ship in distress on the open sea could only send distress signals by Morse code, hoping it would be picked up by another ship near enough (weather permitting) to receive the signal and with a competent operator to decipher the code.
The introduction of satellites almost immediately resolved most of these problems. Messages between ships and any location on the globe could be relayed via satellite. Direct telephone communication between ships and any operational phone anywhere in the world became possible.
Similarly, distress signals when needed could be communicated to the nearest port or rescue station without fail.
By 1976, the International Maritime Organization (IMO) established the International Mobile Satellite Organization (Inmarsat) aimed at providing free distress communications for shipping. Inmarsat pays for this service through the income generated by providing other services to its users.
In the slipstream of Inmarsat, followed the development of the Global Maritime Distress and Safety System (GMDSS), a service that combines established and new techniques and creates a system that would ensure that a distress call from ships would always be heard on land and by other ships; and that distress messages would be sent automatically, even if the ship was overwhelmed by a
sudden disaster.
Maritime communication has improved to the extent that the shipping industry sailed smoothly into the information age with full integration into modern amenities like the Internet, e-mail and even videoconferencing.
SailMail is an association specialising in providing access to websites. Non-essential images and HTML-code is removed, and all vital information is sent to the other connecting member via e-mail.
Telkom is poised to launch a new broadband service via satellite, which would make that facility accessible to ships.
Satellites have also made it possible to go on a cruise around the world without having to miss out on the latest developments in the news or your favourite soapie.
It may be too early to raise any real alarm, but there was a timely warning that space may not be an insatiable resource.
On 11 February, a decommissioned Russian military satellite and one of a network of 66 operational communication satellites of the American company Iridium collided in the first known major space accident of its kind, creating two clouds of debris that were being tracked by experts.
The collision took place nearly 800km above earth over the Siberian Arctic. While cosmic collisions of space junk are not unheard of, the US space agency NASA said it was the first involving two intact satellites.
Some experts are starting to raise concerns about the growing amount of orbital debris accumulating above the earth after more than half a century of human activity in space.
Since the Soviet Union launched the first man-made orbiting satellite Sputnik 1 in 1957, some 6 000 satellites have been sent into space, and according to NASA, in the order of 3 000 remain in operation.
Since the collision, the American Joint Space Operations Center has been tracking between 500 and 600 new pieces of debris, some as small as 10cm in diameter, that were released in orbits between 500 and 1 300km above the earth.
This is in addition to the 18 000 or more other man-made objects already listed, according to the Centre. These pieces from wreckages could be circling the earth and threatening other satellites for as long as 10 000 years to come.
The European Space Agency (ESA) estimates that there are about 13 000 satellites and other man-made objects orbiting earth and only in January this year, did it start a €50-million programme to monitor space debris and to formulate uniform standards to avert collisions.
Jean-François Kaufler, the European agency’s space debris expert, was reported as saying that, ”What the accident showed us, is that we need to be receiving much more precise data to prevent collisions.”
Experts in space debris also met in Vienna in January at a United Nations seminar to seek improved ways of averting crashes. This is to be followed in March by a gathering on space debris at the European Conference on Space Debris.
Despite the warnings over the last 20 years, neither the ESA nor NASA had been able to predict the February collision.
There is a clear need to increase the sharing of information between the world’s space agencies and for international standards for the description, tracking and moving of space debris.
