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Astropolítica

"Se se pudessem interrogar as estrelas perguntar-lhes-ia se as maçam mais os astrónomos ou os poetas." Pitigrilli

Astropolítica

"Se se pudessem interrogar as estrelas perguntar-lhes-ia se as maçam mais os astrónomos ou os poetas." Pitigrilli

Conferência Galileu

Junho 13, 2006

Vera Gomes

No próximo dia 22 irá realizar-se no Centro Cultural de Belém uma Conferência sobre o sistema de navegação por satélite europeu Galileu. Os trabalhos iniciam-se às 9h30 e prolongam-se pelo dia. A língua oficial será o inglês.
Mais informações em: appla.geral@appla.pt ou pelo 21 792 68 10

Report: China’s Military Space Power Growing

Junho 08, 2006

Vera Gomes

By Leonard David

China’s escalating expertise in space is also enhancing its competence as a global military force. Along with lofting future radar, ocean surveillance, and high-resolution photoreconnaissance satellites, China’s rise as a space power also includes pursuit of an offensive anti-satellite system.

Those observations are included in a new report—Military Power of the People’s Republic of China: A Report to Congress—issued by the U.S. Office of the Secretary of Defense.

The annual Pentagon report issued late last month addresses the current and future military strategy of the People’s Republic of China. It takes a look at the current and probable future course of military-technological development on the People’s Liberation Army (PLA) and the tenets and probable development of Chinese grand strategy, security strategy, and military strategy, and of the military organizations and operational concepts, through the next 20 years.

Regional power projection

Underscored in this year’s report as a high priority in China’s military modernization efforts is development of advanced space-based C4ISR and targeting capability. C4ISR in military jargon is short for Command, Control, Communications, Computers, Intelligence, Surveillance, and Reconnaissance.

Furthermore, China’s access to space will continue to improve as it develops newer boosters to replace the aging Long March system, the report stresses. “Acquiring more sophisticated space systems will allow China to expand the reach of its anti-access forces and could serve as a key enabler for regional power projection.”


In the area of satellite reconnaissance, the report notes that China participated in the China-Brazil Earth Resources Satellite (CBERS) program with the CBERS-1 and CBERS-2 remote sensing satellites.

These space assets can take 66-foot (20-meter) resolution images in swaths exceeding 62 miles (100 kilometers), and transmit those digital images to earth stations. “The program will continue with follow-on satellites CBERS-2B, CBERS-3 and CBERS-4, which reportedly increase camera resolution substantially,” the report explains.

Military applications

The Pentagon assessment spotlights China’s interest in acquiring a disaster/environmental monitoring satellite constellation called Huanjing.

A first phase of the Huanjing program calls for three satellites, two of which are equipped for visible, infrared, and multi-spectral imaging. A third spacecraft will possess a synthetic aperture radar (SAR). Phase two of the Huanjing initiative allows for eight satellites: four imaging and four SAR in orbit simultaneously.

“In the next decade, Beijing most likely will field radar, ocean surveillance, and high-resolution photoreconnaissance satellites. China will eventually deploy advanced imagery, reconnaissance, and Earth resource systems with military applications,” the report states.

In the interim, the Department of Defense (DoD) report adds, China will likely supplement existing coverage with commercial systems, utilizing the French SPOT, the U.S. Landsat, Canada’s Radarsat, as well as the American commercial Ikonos satellite, as well as Russian satellite imagery.

Navigation and timing

The Pentagon report also focuses on China’s navigation and timing space attributes, noting that the country orbited three BeiDou satellites to provide navigation coverage with an accuracy of 20 meters over China and surrounding areas.

“BeiDou is an active positioning system that requires transmissions between satellite and the user, slowing the time it takes a user to receive a corrected position. The BeiDou system is best suited for use by troops, ships and vehicles that move slowly. The active part of BeiDou also enables leadership to send and receive secure orders,” the report explains.

In this space application area, the report continues, China also uses the U.S. Global Positioning Satellite (GPS) system and Russia’s GLONASS navigation satellites, and has invested in the European Union’s Galileo navigation system program.

In the human spaceflight arena, the Pentagon report explains that China launched its second manned space mission on October 12, 2005, nearly two years after its first piloted Earth orbiting mission. The two-person crew returned safely on October 17, 2005.

“This was the first occasion during which Chinese astronauts performed experiments in space. Press reports indicate China will perform its first space walk in 2007, and rendezvous and docking in 2009-2012. China’s goal is to have a manned space station by 2020,” the report observes.

The success of China’s human spaceflight program to date “required a substantial amount of systems integration and planning, and serves as an indicator of China’s rapid and relatively smooth rise as an emerging space power,” the report concludes.

In the marketplace

The newly issued report highlights the fact that not only is China expanding indigenous capabilities, it is also marketing its technological space knowledge—satellite building, manufacturing, and launch services—to the international market.

As example, the report describes two international contracts between China and other nations—one with Nigeria and one with Venezuela—for the design and manufacture of communication satellites based on their Dongfanghong-4 (DFH-4) spacecraft.

“China may be developing a system of data relay satellites to support global coverage, and has reportedly acquired mobile data reception equipment that could support more rapid data transmission to deployed military forces and units,” the report states.


Additionally, China is studying and seeking foreign assistance for developing small satellites, lofting a number of them since 2000 for oceanographic, imagery, and environmental monitoring purposes.

China is also developing microsatellites—weighing less than 100 kilograms—for remote sensing and networks of electro-optical and radar satellites,” the DoD assessment notes. “These developments could allow for a more rapid reconstitution or expansion of their satellite force given any disruption in coverage.”

Anti-satellite weaponry

The Pentagon report warns that Beijing “continues to pursue an offensive anti-satellite system,” saying that China can currently destroy or disable satellites only by launching a ballistic missile or space-launch vehicle armed with a nuclear weapon.

“However, there are many risks associated with this method, and potentially adverse consequences from the use of nuclear weapons,” the report adds. “Evidence exists that China is improving its situational awareness in space, which will give it the ability to track and identify most satellites. Such capability will allow for the deconfliction of Chinese satellites, and would also be required for offensive actions. At least one of the satellite attack systems appears to be a ground-based laser designed to damage or blind imaging satellites.”

China is also working on several types of “new concept” weapon systems, the report says, including a radio frequency (RF) weapon, citing Chinese writings that suggest it could be used against satellites in orbit.

Useless compendium

A critic of the U.S. Secretary of Defense-issued report is space policy and arms control analyst, Jeffrey Lewis. He thinks poorly of the assessment and judges it far from a work of scholarship.

Lewis is Executive Director of the Project on Managing the Atom at the Belfer Center for Science and International Affairs, John F. Kennedy School of Government at Harvard University in Cambridge, Massachusetts.

“This report, as in previous years, suffers from the usual defects associated with a report drafted by committee and rushed into print with poor or compromise editing,” Lewis told SPACE.com.

He added that the report’s space section is little more than a laundry list of Chinese space activities.

“A member of Congress or defense analyst looking to argue that China is developing anti-satellite weapons might find such a list useful,” Lewis said. “But an analyst attempting to make a serious, evidence-based assessment should regard the report as a useless compendium of previously established facts lacking the necessary qualifications about what the intelligence community does not know.”

For example, Lewis said that the Pentagon view of China’s laser weaponry proficiency falls short. Previous reports, he added, described limits to what the intelligence community knew about Chinese laser research, noting that “whether this claim extends to actual facilities” or “whether Beijing has tested such a capability is unclear.”

Lewis said that the U.S. Congress ought to create a requirement that the Director of National Intelligence—not the Secretary of Defense—report on Chinese military power.

(in http://www.space.com/news/060605_china_military.html)

Relatório completo em: http://www.defenselink.mil/pubs/pdfs/China%20Report%202006.pdf

Portugal no espaço

Junho 04, 2006

Vera Gomes

Portugal começa a ganhar relevo na exploração espacial. A Agência Espacial Europeia assumiu um grande interesse em instalar na Madeira uma estação de rastreio de satélites do sistema Galileu.
Além da Madeira, também os Açores estão interessados em receber este tipo de equipamento. Mariano Gago referiu que a decisão final cabe à ESA, que já anunciou a sua intenção de abrir concurso. Nesta corrida estão também as Ilhas Canárias.
O projecto para a Madeira baseia-se em tecnologia estatal chinesa e o dos Açores conta com o apoio da Portugal Telecom.
De qualquer forma, o positivo é estas candidaturas contarem com o interese e apoio político do governo português, posição geográfica e capacidade tecnológica.

(fonte: Expresso, 27/05/06)

EADS, Clearstream, and the future of France’s space industry

Junho 04, 2006

Vera Gomes

by Taylor Dinerman

Tuesday, May 30, 2006

It is difficult to imagine a scandal quite like Clearstream in the US, not that we don’t have a lot of our own corruption problems involving politics and the aerospace industry. US examples include the Lockheed bribe affairs of the early seventies and, more recently, the Darleen Druyan Boeing scandal; on the political side we’ve had everything from Watergate, the mother of all them all, to Randy Cunningham and his disgraceful behavior. However, nothing in American history can compare to the unfolding Clearstream scandal in France.
If G. Gordon Liddy, the leader of the Watergate burglers, had been an employee of Boeing or Lockheed instead of an operative of the Committee to Reelect the President, it might be possible to compare Clearstream to Watergate. Instead, this scandal involves at least one senior member of the EADS leadership team. From the corporation’s point of view its involvement in this affair was exceptionally stupid, but since when have human beings, even Frenchmen, been immune from stupidity?
It a nutshell the Clearstream scandal involves a fake list of high-up people involved in French politics and industry who supposedly held illegal accounts at Clearstream, a bank in Luxembourg. The accusation was that these funds were kickbacks from, among other things, the sale of frigates to Taiwan. This dirty trick was intended to destroy the political career of France’s current interior minister, Nicholas Sarkozy. It is strongly suspected that the operations was carried out on behalf of the prime minister, Dominique de Villepin, Sarkozy’s rival, and possibly the French president, Jacques Chirac.
The man at the heart of the scandal is Jean-Louis Gergorin, who earlier this month quit as “Head of Strategic Coordination” at the European aerospace giant. Since then he has been definitively fired. The company naturally claims that Clearstream has nothing to do with EADS. However, the fact is that France’s defense industry is far more intimately involved with the government than in almost any other of the advanced democracies. Gergorin’s career has taken him from the best French universities to the Rand corporation in the US and then to the French Foreign Ministry where, in 1973 under Michel Jobert, he set up a Center for Analysis and Prediction.
Later, he became involved in a nasty fight between Thompson, which is now part of Thales, and Lagardere/ Matra, now part of EADS. Thompson was involved in a nasty scandal over the Taiwanese frigates. At one time he even claimed that “The (French) arms industry was in the hands of the Russian Mafia and that they had assassinated Jean Luc Lagardere (former head of Matra) in 2003.”
Either he is telling the truth on this or he is nuts: in either case it makes EADS look really bad. In the most likely case—that he is paranoid—the question has got to be asked by investors and customers of the conglomerate: how did he get to the top of the organization? Could it have something to do with the fact that the French government owns a 15% “Golden Share” of the company? The company’s customers and partners have got to be asking themselves how many others like him are in management.
For the space industry this means that two of Europe’s most important satellite and launch vehicle manufacturers are now caught up in an ugly political scandal. The corrupt relationships between political power and the aerospace industry in France that have now been exposed will have repercussions worldwide. Anyone in a non-French government or corporation who wants to buy a ride on an Ariane 5, or a satellite or space-qualified component from Astrium, will have to be extremely careful not to get caught up in what promises to be a long and drawn-out affair.
In the US, for example, every single contract the Defense Department has had with both EADS and with Thales will have to be reexamined in minute detail for signs of corruption and/or influence-peddling. No US major defense contractor can allow itself to be seen as having anything other than an arms-length relationship with these two firms until after the Clearstream affair is over and they have fully exonerated of any wrongdoing.
The leadership at EADS has claimed that this case is nothing like Boeing’s Druyan scandal. They are right: it’s worse. Boeing was, at least, abusing the system for its own greedy purposes. Gergorin and his associates were using the resources of the firm to play dirty political tricks on behalf of one ambitious presidential candidate against another.
At the inter-governmental level this scandal will force many of France’s international partners to reexamine their relationships with French government and industry if only to insure that they are not being manipulated for interior French political purposes. Foreign involvement in any aspect of this could involve years of investigations, millions of dollars in legal expenses, and do serious harm to any number of business and scientific relationships.
For the last two decades it has been obvious that the French government has a long-standing strategy to completely dominate Europe’s arms and aerospace industry. To achieve this they are willing to sacrifice any number of things, not the least of which are huge sums of French taxpayers’ euros. Any company that refuses to be “federated” into the French schemes earns itself a label of “Un-European”, as BAE did a few weeks ago when one French commentator called them “A US company with its headquarters in Farnborough”. The extraordinarily tight relationship between this industry and the highest levels of the French state apparatus make Washington DC’s “Iron Triangle” look like a loose tribal confederation.
At a time when the demand for launch services and high end communications satellites is slowly recovering and when the Ariane 5’s teething problems have been put behind it, the Clearstream scandal looks to be yet another obstacle to France’s ambitions to make the EU into a first-rate space power. The other European states, particularly Germany and Italy, who have now subordinated most of their space ambitions to those of Paris, must now rethink to what extent they want to be tightly bound to a company or companies who are now plunged into what promises to be a drawn-out, bitter, and politically destructive struggle.
________________________________________
Taylor Dinerman is an author and journalist based in New York City.

in The Space Policy

Orbital strike constellations: the future of space supremacy and national defense

Junho 04, 2006

Vera Gomes

by Christopher Stone

Tuesday, May 30, 2006

“Victory smiles upon those who anticipate the changes in the character of war, not upon those who wait to adapt themselves after the changes occur.”
– Gulio Douhet

The idea that space should be a sanctuary free of weapons and combat is prevalent in certain circles. However, we should place more emphasis on developing the plans necessary to defend America from and in space. This essay proposes we develop a prompt global strike capability from space, using constellations of orbital strike platforms, and shows why this idea is important in determining the success or failure in future wars.
Space power seems to be, in the words of Gregory Billman, “stymied as a purely supporting force, with no aggressive trend toward realizing greater independent military potential”. Orbital bombardment systems have been discussed since the beginning of the Space Age. One of the perceived threats posed by the launching of Sputnik in 1957 was the potential for an orbiting object to carry nuclear weapons and target any base in the world in a very short time without being able to defend against it. Both the United States and the Soviet Union did research on orbital bombardment systems. However, the United States never really put much effort into that research or potential deployment. That attitude still prevails today for several reasons, some political, others based on traditional visions.
Why do we seem to have such a negative attitude toward the deployment of orbital bombardment groups? Again, we go back to the launch of Sputnik in 1957 when the Eisenhower administration wanted to find a policy that would answer the Soviet launch. Donald Quarles, then Assistant Secretary of Defense for Research and Development, believed the Russians unintentionally helped our strategic position by establishing the concept of freedom of international space. He believed that this idea, known today as “Sanctuary” theory, was critical to US intelligence gathering in space. Also, it would alleviate political implications and possible fears of starting a war with the Soviets. Since the end of the Cold War, we have adhered to the policy of freedom of space since our space assets have not been threatened by any other spacefaring nation. This policy, while good intentioned, may be a weakness in the future of American security. Many nations, namely the Chinese and the Russians, have formed separate military space services and have stated their intentions to push out into space and to challenge current American space superiority.
Regardless of how controversial these space weapons platforms may be to countries such as China or Russia, these weapons can and should be developed. According to Lt Col John M. Amrine’s paper “Command of Space,” “…the US needs to face three realities. First, the US has an enormous investment in space that continues to grow. Second, space weapons typically have a long development cycle and third, the nation’s ability to control space is severely limited.” If we do not develop space weapons now, and field them sooner rather than later, the US will have limited options for responding to an attack.
Our space assets are vulnerable. As General Lance Lord, former Commander of Air Force Space Command, stated at the Air Force Association’s National Symposium in November 2005, “Some would say we are not threatened in space, I want to disabuse everybody of that argument.” The general also said that we “cannot assume that space is benign and that we’ll never be challenged in that environment.” As a temporary means of guarding our space assets, Lt Col Amrine proposes to deploy terrestrial-based weapons that can have a wide variety of capabilities to deny space based threats. I agree with that as a starting point, but waiting until the threat becomes “more apparent” may be too late and may invite the “Space Pearl Harbor” that Col Amrine and the Space Commission members want to prevent. We need only look to recent history and the September 11, 2001 attacks to see that waiting for threats to become more apparent could result in thousands of American deaths and massive destruction in our cities.
What are the advantages of space-based attack constellations? One is that of persistent global presence, using the aforementioned freedom of international space. One researcher notes, “Constellations orbit without violating national sovereignty, having freedom of overflight. Three satellites in geosynchronous orbit can observe most of the surface of the Earth, minus the poles.” He also states that twenty-four navigation satellites in medium orbit provides surface users visibility of three or more satellites at a time. This is called virtual presence since the vehicles are mostly out of sight and unperceivable from the ground. Col Fredriksson states that this virtual presence would be substantial for basing weapons in space as well as facilitating nearly instantaneous global response. He calls it “strategic agility” whereby we could strike rapidly, over global distances with appropriate capabilities.
Our nation is dependent on space assets for everything from battlefield communication to direct-to-home TV. Why wait to defend our interests in space and on Earth with space-based defenses? Billy Mitchell stated, “National safety would be endangered by an air force whose doctrine and techniques are tied solely to the equipment and processes of the moment. Present equipment is but a step in progress, and any air force that does not keep its doctrine ahead of its equipment, and its vision far into the future, can only delude the nation into a false sense of security.” We should move beyond just writing theory and doctrine and start developing effective defenses in space that could be more reliable as well as cost effective in the long term compared to terrestrial forces.
The United States, as permitted under international and domestic law, has the right to defend itself against threats. The Space Commission report states that the United States reserves “the right to be able to retaliate or destroy” either ground sites or satellites, if necessary. Because of the rising threats to our space assets, America needs an ability to negate or destroy threats whether temporarily or permanently. Test ranges will be needed to test these abilities and perfect them. The fact that potential enemies would undoubtedly see these exercises, would help strengthen deterrence. With orbital bombardment groups, the United States would have a deterrence capability that would no longer rely solely on nuclear weapons to intimidate a potential aggressor.
Having orbital bombardment groups would offer a distinct military advantage over future adversaries. We would have the ability to affect air, land, and sea forces by projecting power from space anywhere in the world with very little time needed for mobilization. Unlike weapons launched from air, land, or sea, space bombardment groups could execute operations with little transit time or weather delays. This would provide the United States with a clear time on target advantage over enemy forces.
Are there prohibitions against basing orbital bombardment systems in space? No, but there are prohibitions against nuclear or other weapons of mass destruction due to treaties such as the Outer Space Treaty of 1967. However, Article 3 of the Outer Space Treaty does allow nations to prepare for “anticipatory self defense” in space. Also, the non-interference between nations’ satellites codified by other space treaties would be suspended during hostilities as the laws are currently written.
Mastery of space, which is vital to our national security, includes the need to reduce the costs of operations in relation to terrestrial alternatives. Orbital bombardment constellations would reduce long-term cost by permanently being in position compared with terrestrial forces that would need to be deployed. This would reduce the need, as well as cost, of forward deploying aircraft and personnel by not having to pay salaries, gain permission for basing rights, etc. As Greg Billman states in his analysis of perceived limits of spacepower, “As forces [terrestrial] are deployed, economic costs of all kinds tend to increase… field conditions require additional housing, food, water, transportation, medical care, maintenance and other things as these must be afforded apart from an established base.” Equipment tends to break and people tend to get injured or killed more than when home based. However, space-based systems would likely be less susceptible to damage or loss than terrestrial forces.
Unlike terrestrial forces, space forces do not require escalating support and operational costs upon deployment and engagement. Maintenance costs can be drastically reduced by a lift capability allowing either on-orbit replenishment or rapid, contingency-oriented delivery capability. While attack squadrons are in day-to-day operations, all that would be needed is occasional reboost and refueling which can be accomplished by either annual or decadal launches of refueling spacecraft or by basing orbital tankers that could link up with the satellites based on new advanced remote control technologies. The latter would most likely cost more than just occasional launching of such refuelers.
Given a more supportive policy toward space weapons, Billman states, “a force structure could be created that allows both maximum political flexibility and max military flexibility—a fully mission capable space force, coupled with a well proportioned terrestrial force. With such a force, the possibility may exist for long tern fiscal savings through a decreased terrestrial force infrastructure and long term manpower and equipment sustainment cost savings”. This would actively support the Air Force’s stated policy of wanting systems that “actively support Global Reach/Power by lessening reliance on forward basing as well as supporting aerospace power objectives of flexibility, range, responsiveness and lethality.”
________________________________________
Christopher Stone (BA University of Missouri) is a space/missile officer with Air Force Space Command-Reserve Component.

in The Space Review

Quem inventou o GSP?

Junho 04, 2006

Vera Gomes

Who invented the Global Positioning System?
by Richard Easton

Alexander von Humboldt observed that there are three stages in scientific discovery: first people deny that it is true; then they deny that it is important; finally they credit the wrong person.
—cited in A Short History of Nearly Everything, by Bill Bryson, p. 421
Arguments are rife over priority in major scientific and technological advances. An example is the role of Newton versus Leibnitz in the development of calculus. Another is the controversy over Langley versus the Wright Brothers in the airplane. For many years, the Smithsonian put forth the claim of Langley, its former head, and the Wright Brothers boycotted it. (Captain Philip Van Horn Weems, who helped resolve this controversy, played a major role in aviation navigation and later played a peripheral role in the developments recounted below.) The Smithsonian dropped its claim about Langley and Orville Wright allowed the Smithsonian to exhibit the Wright planes. Similarly, the origination of the Global Positioning System (GPS) is in dispute.

The Global Positioning System has revolutionized our society. It has greatly improved the accuracy of weapons. It has added billions to the economy with its applications in agriculture, trucking and many other industries. Many lives have been saved since hikers and others with GPS devices can more easily find their way to safety. Yet, there is disagreement over who created it.

Many are unaware of the controversy. Thus, readers of the American Heritage Magazine of Invention and Technology learned on page 58 of the Fall 2004 issue that:

[Brad] Parkinson was inducted into the National Inventors Hall of Fame in May for his leadership of the military project that created the GPS system. Along with Ivan Getting, an early proponent of GPS, and many others, Parkinson helped create a navigation and positioning system…
It all began in 1973, when then Colonel Parkinson, of the U.S. Air Force, was appointed to lead a joint military program to build an advanced navigation system. When he arrived, competing factions from the Navy, Air Force, and other services, each promoting its own technological solutions, were threatening to sink the project. “It was a mess,” he says. His first duty was to find a compromise plan that all the services could support.
Note that Parkinson does not state how much of each service’s technological solution was used in GPS. The magazine does include the phrase “many others”; however, since it does not mention any other individual, the clear implication is that Getting and Parkinson played a more significant role in GPS than anyone else.

The Inventors Hall of Fame gives priority to Getting for GPS:

The technological triumph known as the Global Positioning System of satellite based navigation was incubated in the mind of Ivan Getting. While serving as the vice president of research and engineering at the Raytheon Corporation during the 1950s, Getting advanced the concept of using an advanced system of satellites to allow the calculation of exquisitely precise positioning data for rapidly moving vehicles, ranging from cars to missiles.
Elsewhere, Parkinson emphasized the importance of the Air Force’s program to the development of GPS, and alleged that there were serious problems with the Navy’s program, called Timation, under development at the Naval Research Laboratory:

The Space and Missile Systems Organization pushed a program called 621B, which used a signal that employed pseudo-random noise to resist jamming. Unlike the various Navy systems, 621B provided altitude, as well as latitude and longitude. “To the Navy, navigation is essentially a two-dimensional problem, but the Air Force was definitely interested in the third dimension”, Parkinson said. The 621B system was tested using aircraft between 1968 and 1971… Timation was easy to jam and only two-dimensional.
The clear implication from these passages is that the Air Force’s technology was more important than the Navy’s in GPS. However, in an August 20, 1973 article in Aviation Week and Space Technology, Philip J. Klass wrote, “an Air Force spokesman expressed admiration the technical expertise of the Naval Research Laboratory team, headed by Roger Easton, that has carried out the Navy program.”

The Global Positioning System has revolutionized our society. Yet, there is disagreement over who created it.
On February 13, 2006, my father, Roger Easton, received the 2004 National Medal of Technology from President Bush for “his extensive pioneering achievements in spacecraft tracking, navigation and timing technology that led to the development of the NAVSTAR-Global Positioning System (GPS).” The American Philosophical Society awarded the Magellanic Premium in 1997 to both Roger Easton and Bradford Parkinson. Their awards were worded identically, “for essential contributions to creating the Global Positioning System, thereby making the tools for precision navigation available to everyone.” In 1998, Roger Easton was inducted into the American Philosophical Society for his work on GPS. However, Easton was not mentioned in the American Heritage article nor was he cited by the National Inventors Hall of Fame.

So, which service’s technology is the basis of GPS? The evidence shows that GPS is essentially the Navy’s system, Timation, and does not use in any significant way the Air Force’s system, 621B. The clear evidence makes it astonishing that the opposite has been implied in articles.

Thus, senior editor Philip J Klass wrote on page 46 of the November 26, 1973 issue of Aviation Week and Space Technology:

The program also has been renamed the Global Positioning System to reflect better its principal mission for weapons delivery and the high accuracy potential of the system.
The ability of the USAF and Navy to resolve their long-standing differences over the orbital configuration by adopting basically the Navy-proposed constellation arrangements [emphasis mine] has eliminated one of the major obstacles to Pentagon approval for the program.
As Easton said in his acceptance speech for the Magellanic Premium, “On the Labor Day weekend, 1973, the Air Force accepted the Navy technology for satellite positioning, and here I salute Dr. Parkinson for knowing a good technology when he sees it.”

Parkinson’s assertion that Timation was two dimensional (latitude and longitude only) is wrong. It was three-dimensional. Thus, Klass wrote in the August 1973 Aviation Week article:

As additional Timation satellites are deployed, it becomes possible to make position determination on a three-dimensional basis (including altitude) on a more frequent basis.
Finally, with a total of 27 spacecraft deployed, a full 3-D continuously available position-fixing capability is provided.
So, which service’s technology is the basis of GPS? The evidence shows that GPS is essentially the Navy’s system, Timation, and does not use in any significant way the Air Force’s system, 621B.
Chester Kleczek, at the Bureau of Naval Weapons, was a strong supporter of Timation. He faced much opposition, as did Easton, from advocates of existing systems. At one point, an opponent from the Department of Defense commented that 43 navigation systems already existed. Kleczek asked which of them could give a Navy pilot his altitude in the South Pacific. None of these 43 systems could do this and so funding was obtained. Thus, an essential argument for Timation was its ability to give three positions. Parkinson’s comment that the Navy was only interested in two dimensions is silly in light of the importance of aircraft from aircraft carriers.

Further evidence of the Navy’s essential role in GPS comes from the Summer 1998 issue of the Institute of Navigation Newsletter:

Special recognition during the jubilee [75th anniversary of the Naval Research Lab] was given to Easton, an engineer at NRL for 37 years and the holder of basic patents relating to GPS. Easton worked on the design of 25 satellites while at NRL, according to an NRL information kit. In 1964, Easton put together the concept of using atomic clocks in satellites to fix the position of receivers listening passively to satellite transmissions, a one-way ranging technique that included a simplified method for interpreting the information received from the clocks. His 1964 concept was recognized in 1974 with U.S. patent 3789409 entitled “Navigation Systems Using Satellites and Passive Ranging Techniques.” Many persons deserve credit for making essential contributions to the development of GPS, but Easton’s filing is the enabling patent.
The basic configuration of Timation, 621B, and GPS is given in the table below. Clearly, GPS is Timation with a different signal. The interested reader can find many of the details in the August 1973 Aviation Week article by Klass.

Characteristic Timation 621B GPS
Number of satellites 27 3 or 4 groups of 5 24 satellites and 3 spares
Orbits 12,875 km (8 hour orbit, though the 12 hour orbit was also proposed) Geosynchronous or near geosynchronous or high altitude circa 40,000 km 20,300 km, 12 hour orbits
Signal sidetone range Pseudo random sequence Pseudo random sequence
Time setting on satellites Atomic clocks on each satellite - periodic updates from ground stations No clocks on satellites - time transmitted from seven ground stations Atomic clocks on each satellite - periodic updates from ground stations

A pioneer who had a similar idea to GPS should be mentioned. Roy Anderson, from General Electric, proposed to NASA in 1959 a satellite system for navigation using active receivers. It would have worked only when the sun was on the satellites. This probably reflected the primitive state of batteries at the time. However, this scientist deserves mention for being ahead of his time.

Parkinson has mentioned that a problem with Timation was that its signal, called side tone ranging (STR), was vulnerable to jamming. GPS uses pseudo random noise (PRN). It’s true that STR is slightly more vulnerable to jamming than PRN. However, it has the significant advantage that it produces a stronger signal. This would have mitigated the persisting problem that GPS does not work well in the woods or in houses with metal roofs. Parkinson agreed with Easton that they would use both systems; however, GPS only uses PRN.

One might ask why a group led by an Air Force colonel was given the responsibility to run a program using Navy technology. The Air Force was given the lead in space programs by the Department of Defense. Frank Ault, who was in charge of Transit and Timation, would have run GPS if the Air Force had not been given it. He very successfully ran Top Gun and doubtless would have done a good job on GPS.

Chester Kleczek, the Timation advocate mentioned earlier, deliberately did not ask about certain technical details of the system since he feared that others would claim credit for it. However, Mr. Kleczek says that the Russians became aware of it after the 1967 launch of the first test satellite and based their system, Glonass, on it. It would be interesting if experts on the Russian space program could confirm this.

However, Project 621B played a major role in the development of GPS: not because of its technology, but because the Air Force was willing to fund GPS to an extent that the Navy and civilian agencies were not.
Any large program like GPS depends on the work of many talented people. Two of Easton’s co-workers at the Naval Research Lab, James Buisson and Thomas McCaskill, ran a program on a mainframe to review different orbits and find the one which optimized the precision of the system. They arrived at a very precise answer that is still used today. Another co-worker, Don Lynch, calculated the relativistic shift that was important to synchronizing the time on the 24 satellites. Other important contributors at NRL included Charles A. Bartholomew and Randolph Zirn. An important outsider was Robert Kern; his firm manufactured the atomic clocks used by GPS satellites.

So what were the contributions of Parkinson and Getting to GPS? Parkinson deserves much credit for doing a good job of developing the program. Getting may have contributed to other important programs, but being a supporter of GPS does not make him an inventor of it. However, Project 621B played a major role in the development of GPS. Not because its technology was important for GPS; as I’ve proven, it wasn’t. In a telephone interview, Harry Sonneman, chairman of the Navigation Steering Committee at the Pentagon, commented that 621B pointed out to the Air Force the potential of a precision satellite-based navigation system. At the time, the projections were that the Air Force would lose many bombers in an attack on the Soviet Union. A precise navigation system could reduce these losses. In addition, the many failed attempts to knock out North Vietnamese bridges highlighted the need for more precise weapons systems. Thus, the Air Force was willing to fund GPS to an extent that the Navy and civilian agencies were not. However, GPS used primarily Timation’s technology as pointed out above.

Another advantage of Timation that both Klass and Sonneman mention is that it would provide useful information with as few as three satellites. 621B required at least four or five satellites for functionality, and no additional utility arises from 621B until the second cluster of satellites is complete, whereas Timation’s utility increases with each satellite from the third one onwards. In addition, the Navy tested some of the 621B orbits to obtain polar coverage and found them to be unstable. Considerable fuel would have been needed to maintain these orbits. Sonneman commented that one of the 621B satellite clusters would have been over the Soviet Union. This would have been a political nightmare as the Soviets doubtless would have claimed that they were spy satellites. Timation’s satellites, and GPS’s, orbit over the entire Earth and thus are not subject to this objection. In addition, Sonneman states that the ground stations, up to seven, needed for 621B would have been protested as were the ground stations for another contemporary system, Omega. Another disadvantage Sonneman mentions is that the close proximity of the 621B satellite clusters would have made them vulnerable to a single nuclear bomb or even conventional weapon attack.

Besides the signal, the sole potential advantage I found in the literature for 621B was that air surveillance of friendly forces and data communications could be added easily to the system.

The evidence shows that Roger Easton invented GPS and is finally getting credit for it as shown by his receiving the National Medal of Technology. Parkinson deserves much credit for his successful development of the system, but neither Parkinson nor Getting invented it. Further study about GPS has reinforced my prior understanding that the Navy had the technology and the Air Force had the money to fund it.


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Richard Easton (winnetkaelm@comcast.net) has degrees from Brown University and The University of Chicago. He works as an actuary for an insurance company in Glenview, Illinois.

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