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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

Nasa and Esa: a parting ways?, por Taylor Dinerman

Janeiro 28, 2006

Vera Gomes

Last month’s ESA ministerial meeting in Berlin failed to provide observers with any of the fireworks that some observers expected. There were no major project cancellations or any real program reforms. They agreed to give preference to European launchers, which may be bad news for Russia’s space industry unless somehow the EU finds a way to define the Proton as “European.” The ministers also failed to provide the Aurora solar system exploration project with the increased funding needed to prepare for independent European human space exploration.

Instead, they agreed to continue work on the ExoMars project, planned for a launch in 2011. This will be a Mars rover with instruments designed specifically to search for signs of life on Mars. It should be a fascinating endeavor that, even if it fails to find traces of organic life, will provide the scientific community with a wealth of data on the nature of the Red Planet.

The meeting also reaffirmed ESA’s new paramilitary role, both with Galileo and with the GMES (Global Monitoring for Environment and Security) remote sensing program. ESA is becoming less and less a civilian space agency dedicated to science, technology, and exploration and more and more an institution dedicated to enhancing the power and prestige of the European Union, which leaves the non-EU members and associates of ESA, such as Switzerland and Canada, in an increasingly uncomfortable situation.

ESA is evolving into a unique organization whose main ambitions involve France’s long-standing desire to make “Europe” into a new superpower, rather than the more prosaic goals of other Europeans who want ESA to help provide them with a better standard of living, a cleaner environment, and more productive economy. ESA is not abandoning science and exploration any more than NASA is giving up on its aviation technology research programs. These are simply no longer important priorities.

NASA is emphasizing the completion of the final shuttle flights and the design and development of the Crew Launch Vehicle and the Crew Exploration Vehicle. It is following the Bush Administration’s vision as reaffirmed by the US Congress in last December’s NASA authorization bill. In Washington, 2005 will be remembered as the first year since the era of Apollo that both the executive and legislative branches came to a firm agreement on the future goals for America’s human spaceflight program. NASA administrator Mike Griffin’s main task will be to sustain and broaden this consensus. Getting back to the Moon and staying there is going to be at least a twenty-year-long effort, and doing so will require both political will and budgetary discipline.

ESA, with its much smaller budget, still wants to do a little of everything. It wants to support Europe’s launcher and satellite industries. It also wants to support robotic exploration and its aforementioned quasi-military role. It will also continue its partnership with the US, Russia, and Japan on the International Space Station. Jean-Jacques Dordain, ESA’s Director General, announced that, sometime this year, they will be shipping the Columbus laboratory module from Germany to Cape Canaveral, to be delivered to the ISS on a future shuttle mission. He said, “We can permit ourselves to be confident that Columbus will be launched and utilized.”

According to ESA, they are now on track to launch the Jules Verne Automated Transfer Vehicle (ATV) to the ISS sometime in 2007. For both the Europeans and for the space station, this will be a major step forward. The ATV will be one of the major resupply systems needed to keep the station operational after 2010, when the shuttle is retired. Russia’s Progress capsules have done excellent work since the Columbia disaster, but it is now showing its limits. If the larger ATV is a success, it will be an important factor in any decision to increase the ISS crew size.

Dordain also announced that ESA will begin talks with the Americans on their participation in NASA’s lunar exploration program. This will be tricky since Griffin has made it clear that all the elements in the so-called “critical path” will be American. In this he really had no choice. There is little appetite for international cooperation on Capitol Hill. The foreign policy arguments that the Clinton Administration used to promote the ISS in 1993 and 1994 no longer apply. America is planning to go back to the Moon. If it succeeds it will be an American triumph; if it fails, it will be an American failure.

There is room for cooperation in the various scientific aspects of the program. Data will shared and there will be lots of room for European instruments to fly on US space probes (and vice versa) and even for European astronauts to travel to the Moon on American CEVs. However, the US government has made it plain: the command and control of this effort is going to remain in Washington.

Philosophically, this is not going down well in Europe. Their belief in multilateralism for its own sake, and their distaste for the Bush Administration, to say nothing of generic anti-Americanism, puts limits on their willingness to be “loyal followers” in any blatantly American-led program.

Last September, writing in the left wing Paris newspaper Liberation, Sylvestre Huet wrote: “To go back to the Moon to build a scientific base, to prepare for a Mars mission that will help to discover the origins of the solar system and its relations or not with life on Earth… This looks like an open, peaceful program of scientific cooperation, with no one showing any will to dominate it and one that needs a regular source of financing. Bush or any his successors who want to imitate Kennedy and his show of force will not carry out such a program. The European Union could do so if it wanted to, with a rational and progressive program, structured around scientific objectives, and one day, under the flag of the UN.”

This is as good a representation as any of what the Europeans want to see happen. It is not what the US wants or is ready to pay for. This fundamental political incompatibility will continue to haunt any effort to restore close cooperation between the US and the European space programs.

EU-US chronowar, por Taylor Dinerman

Janeiro 22, 2006

Vera Gomes

When the Europeans claim that their new Galileo satellite navigation system will be more accurate than the US GPS, many in this country dismiss it as typical European bluster. For example, at their Lisbon meeting in 1999, they claimed that they were going to establish themselves as the most competitive information-based economy in the world by 2010. The Galileo project itself is the subject of numerous absurd claims, such as the idea that it is a civilian system and that it will create more than 100,000 jobs in the EU. However, not all of their claims should be ignored based on previous experience with Europe’s rhetorical excesses.

While it is probable that Galileo will not provide a significantly more accurate positioning system than GPS, especially when GPS 3, in its new orbital configuration, becomes operational in five or six years, the all-important timing signal from the Galileo system will, if all goes as planned, be more than an order of magnitude more accurate that the one from GPS 2R satellites. If the next generation of US space-based atomic clocks cannot do better, this will devastate American influence on everything from cell phone chip design to electronic funds transfer and communications systems. Control of an important element of the information age will pass from the US to an international consortium led by the likes of France and China.

Since the beginning of the GPS program, the US has used cesium and rubidium atomic clocks as the source of the timing signal. By any normal standard, these are amazingly accurate, to within about ten nanoseconds or less. Many years ago, the Naval Research Laboratory (NRL) suggested that a device called a hydrogen maser (microwave amplification by stimulated emission of radiation), which could provide sub-nanosecond accuracy, be used on future GPS satellites. The managers at both the Air Force and the multiagency Interagency GPS Executive Board rejected this idea as being too expensive.

Last year, the Air Force gave Symmetricom the contract to develop and eventually to manufacture the atomic clocks for the GPS 3 constellation. A spokeswoman for the Space and Missile Systems Center said that the hope was for a program that “will emphasize improved frequency stability and integrity of output signal.” The new clocks will use a proprietary “optically pumped, cesium beam technology.” The company expects that their technology will fully match the accuracy of the European clocks.

In fact, a hydrogen maser costs only about $250,000 more than a cesium clock, according to one source. The idea that the US government would turn away from a radical improvement in GPS capability over such trivial sums, when its spends more than a billion a year on the program as a whole, and as much as $400 million a year on research and development, is, frankly, incomprehensible.

On the other hand, we are dealing with a government bureaucracy that is probably comfortable with, and thoroughly understands, the rubidium/cesium technology. According to another source, there is also a good operational reason to stick with these clocks. They provide for a much more robust system which has a better chance of surviving attacks or accidents. Obviously, rubidium, cesium, and hydrogen masers have various advantages and disadvantages. The designers of any satellite navigation system have to take these into account.

The Europeans, who are building their program from scratch, understood, and intend to exploit, the promise of hydrogen masers. They are going to be launching an experimental one on their Giove-B satellite later this year. Their system is partly based on technology they obtained from Russia, which has long experience with masers. Made by a cooperative venture between Italy’s Galileo Avionica, which provides the electronics, and the Neuchatel Observatory and the company Temex Neuchatel Time, based in Switzerland’s traditional watch-making region, who are building the core. They hope to succeed in building and space-qualifying a passive hydrogen maser that will weigh less than 15 kilograms.

This is in contrast with the washing machine-sized active hydrogen masers made by Symmetricon. The US masers currently used by the Naval Observatory weigh in at about 250 kilograms. (It is interesting to note that this company seems to have a lock on all US ultra-precise time measuring systems.) NRL has, in storage, a few small masers that they hoped would be flown on an experimental satellite. This project should be revived. There are a few small satellite manufacturers that could put such a bird together on fairly short notice. It could be launched as a ride along payload on a larger Delta 4 or Atlas 5, or it could be orbited on a smaller rocket, such as the Pegasus or the Falcon 1, assuming they have a successful first flight next month.

It was reported that a little while ago, Defense Secretary Donald Rumsfeld sent one of his famous “Snowflake” memos to the Air Force, demanding to know why they had, so far, failed to carry out his instructions to accelerate the development and deployment of GPS 3. One speculates that the reasons for this involve the need for ever greater precision on an ongoing worldwide basis. The GPS operators can “tweak” the system today to get sub-meter accuracies in certain areas of the globe, such as Iraq. There is no way to predict where such accuracy will be needed in the future.

The natural desire of the Defense Department’s leaders for a better GPS system, as soon as possible, conflicts with the possible need to revamp the whole GPS 3 program to include hydrogen masers. It is a dilemma that could be resolved with more resources. In today’s budget environment, it seems doubtful that there will be more money available. So the answer might be to continue to build the a few more GPS 2R satellites while working hard to make the GPS 3 satellites have even more accurate timing systems than is planned for Galileo.

The Europeans have what is sometimes called the “second mover advantage.” The US has pioneered the GPS concept and the Europeans and their allies are going to try and take advantage of America’s possible missteps by building a better system. It may be prudent to take the claims made for Galileo’s superiority over GPS 3 with a few grains of salt. No one can be certain one way or the other. The US can take the bull by the horns and choose to develop an even better system, thus wrecking their hopes to dominate the satellite navigation market. In any case, the US must now recognize that it is in a “chronographical arms race” with the EU, and it cannot be passive.

________________________________________

Taylor Dinerman is an author and journalist based in New York City.
(fonte: http://www.thespacereview.com/article/534/1)

Artigo de Opinião de Miguel Monjardino publicado no Expresso de 6 de Janeiro

Janeiro 15, 2006

Vera Gomes

A fronteira final


Na madrugada do dia 28 de Dezembro a Europa deu o primeiro passo num projecto com enorme potencial político e estratégico quando um foguetão russo partiu para o espaço do cosmódromo de Baikonur, Cazaquistão, com o pequeno satélite europeu Giove-A. Durante os próximos meses, este pequeno satélite testará os relógios, o efeito das radiações e as frequências a usar pelo projecto Galileu, um ambicioso projecto espacial da Agência Espacial Europeia, União Europeia, empresas privadas e parceiros estrangeiros como a Índia, Israel, China, Ucrânia, Marrocos e Arábia Saudita. Orçado em 3.6 biliões de euros, o Galileu tem por objectivo colocar em órbita nos próximos anos trinta sofisticados satélites que permitirão uma navegação muito mais precisa e fiável do que a actualmente fornecida pelo sistema americano GPS. Um projecto tão ambicioso como este só será possível se todos os parceiros envolvidos conseguirem ultrapassar uma série de importantes obstáculos tecnológicos, financeiros e burocráticos. Uma presença permanente e fiável no espaço, a nossa fronteira final, é algo que nunca será nem barato nem fácil.

A presença do Velho Continente na fronteira final terá importantes consequências para as sociedades europeias. Para começar, o projecto Galileu será um importante empurrão para a indústria aeroespacial europeia, uma indústria absolutamente crucial hoje em dia. No caso de ser bem sucedido, a Comissão Europeia estima que o projecto possa ainda criar até 150.000 novos empregos na Europa. E numa altura em que a nossa dependência diária em relação à navegação por satélite é cada vez maior, um sistema como o Galileu terá um enorme potencial comercial. As vantagens serão também assinaláveis nas áreas da segurança e serviços de emergência.

O mesmo se diga do seu potencial político e estratégico. Na génese do Galileu está a ambição dos países europeus de diminuir a sua actual dependência em relação ao sistema GPS, um sistema facilmente acessível por qualquer interessado mas controlado pelos militares norte-americanos. Em caso de guerra, Washington tem sempre a possibilidade de restringir o acesso ao GPS ou de degradar a qualidade da informação fornecida a terceiros. Do ponto de vista político, o monopólio norte-americano no sistema de posicionamento global por satélite tem sido uma situação extremamente incómoda para os líderes europeus. Philippe Douste-Blazy, ministro dos Negócios Estrangeiros da França, não exagerou pois quando disse que o Galileu representa "a independência da União Europeia" em relação aos EUA nesta matéria.

Esta promessa de independência terá importantes consequências estratégicas. Não deixa de ser curioso notar que este ponto tem sido muito pouco acentuado pelos decisores políticos europeus. O que estes decisores acentuaram acima de tudo nos últimos dias foram as dimensões civil, tecnológica e comercial do Galileu. É verdade que a Agência Espacial Europeia está proibida de tomar parte ou financiar projectos militares. Mas também é óbvio que um sistema com tantos satélites em órbita e um grau de precisão tão elevado terá aplicações militares. A realidade é que o espaço é cada vez mais importante em termos estratégicos. O poder espacial, ou seja, o uso do espaço e de meios colocados no espaço para aumentar e projectar o poder militar é cada vez mais importante para países como os EUA, Rússia, China, Índia, Japão e alguns países europeus. O modo americano de fazer a guerra, por exemplo, com o seu ênfase no domínio da informação e ataques precisos a grande distância, seria impossível sem meios espaciais. Nas próximas décadas, quando os países europeus combaterem ou tentarem impôr a paz em regiões longe da Europa, a nossa dependência em relação ao espaço só poderá aumentar.

Quando se fala em coisas como poder espacial e a dimensão estratégica do espaço a reacção mais natural das pessoas é dizer que a última fronteira não pode ser militarizada. Mas este não é o verdadeiro problema. Por uma razão muito simples: o espaço tem sido profundamente militarizado desde 1961-1963, altura em que os EUA colocaram em órbita o satélite de reconhecimento Samos 1 e a primeira constelação de satélites para apoiar os seus submarinos com mísseis balísticos nucleares Polaris. Mas nem tudo foi mau na militarização do espaço. Os satélites de reconhecimento permitiram enorme transparência durante a Guerra Fria e ajudaram a manter a paz. Agora que o espaço é crucial do ponto de vista estratégico, a verdadeira questão é saber até que ponto vai haver guerra pelo controlo e acesso à ultima fronteira. A história estratégica sugere que mais tarde ou mais cedo tal acontecerá. Pensar estrategicamente sobre o espaço é pois para os europeus cada vez mais importante.

US retiram U-2

Janeiro 06, 2006

Vera Gomes

AA classified budget document approved by the Pentagon Dec. 23 calls for the termination by 2011 of one of the most heavily relied-upon reconnaissance planes in the Iraq war.

The storied U-2 spy plane would commence retirement in 2007 under the strictures of Program Budget Decision, or PBD, 720, according to Pentagon, defense industry and congressional officials familiar with the document.

All spoke on condition of anonymity because the decision is classified.

PBD 720 would retire three U-2s in 2007, six in 2008, seven in both 2009 and 2010 and the final 10 in 2011.

The document, one of a host of similar decisions approved in an annual ritual by senior defense officials as the finishing touches are being put to the department's budget request, does not explain the rationale for terminating the program, which has been unsuccessfully targeted for retirement multiple times in the last 10 years.

The decision emanated from the Quadrennial Defense Review deliberations, officials told United Press International. The review will be published early this year.

According to an undated Air Force briefing chart, the U-2 flew 19 percent of the air reconnaissance missions during the 2003 Iraq invasion but provided more than 60 percent of the signals intelligence and 88 percent of battlefield imagery.

The U-2, built by Lockheed Martin's Skunk Works, would likely be supplanted by the Northrop Grumman's high-altitude Global Hawk unmanned aerial vehicle; and champions of the venerable spy plane believe the U-2 termination is meant to hasten the transition away from manned toward unmanned reconnaissance. As long as the U-2 is performing these missions and is available, there is less impetus to develop unmanned platforms and space systems, the high-tech systems heavily favored by Defense Secretary Donald Rumsfeld's Pentagon.

Five years ago, then-Air Force Secretary F. Whitten Peters suggested the termination of the U-2 program in 2011 to free up funding to boost production of the nascent Global Hawk. But this and other attempts to retire the U-2 have been rebuffed by Congress.

"There has been a push for a long time and one has to wonder what the push is, and one is that it is a rationale for all to drive the Global Hawk on," said a Capitol Hill official who spoke to UPI on condition of anonymity.

The U-2 was first developed in the 1950s, and put into production again in the 1980s. Between 1995 and 1999 the entire fleet received new engines.

These upgrades, along with a new glass cockpit and new sensors, give it useful service life until 2050, according to a Congressional Research Service report from 2000.

The unmanned Global Hawk can fly twice as far as the U-2 and remain on station for three times as long. However, the U-2 can carry twice the payload as the Global Hawk and its superior electrical power from new engine increases some of the capabilities of its onboard sensors. The next generation of the Global Hawk is slated to boost its payload weight and an electrical generator to roughly match the U-2, according to information provided by Northrop Grumman.

The two aircraft have for the last five years been operating as complementary as bugs have been worked out of the relatively new Global Hawk, which suffered two major crashes in Afghanistan in December 2001 and July 2002.

Northrop announced this week the Global Hawk had exceeded 5,000 combat flight hours and flown 233 missions, 157 by a single aircraft. Six Global Hawks have been deployed in the Iraq and Afghan wars. The Air Force currently plans to purchase 51 more of the $50 million craft.

The difference between the aircraft goes beyond the sensors they carry and how long they can fly. A piloted aircraft can be redirected in flight to new targets; the Global Hawk is pre-programmed. Moreover, there are places where the FAA, international aviation regulations or host countries prohibit unmanned aircraft for safety reasons.

"We don't have the benefit of the QDR insights," said the congressional official. "But this is like saying, which one is better a Ford 500 or a Mercedes roadster? The Ford doesn't have a top that can come down. On the other hand you can't put a family of five in a roadster."

There may be a third option in what appears to be an either/or trade-off between manned and unmanned systems: making the U-2 an "optionally piloted vehicle" or OPV with the installation of a new command and control system.

The House of Representatives directed the Pentagon to support the development of the "OWL" OPV in 1998 for counter-drug and border enforcement missions. Sources suggested this might be a way to straddle the gap between the sensor capabilities of the U-2 and the loiter time of the Global Hawk.

The U-2 is a single engine, single-seat aircraft built for flight -- it is almost entirely wings. Flying above 70,000 feet to avoid detection and attack, pilots have to wear spacesuits to protect themselves from low pressure and oxygen starvation.

They affectionately call it the "Dragon Lady" because of its difficult handling at altitude, and the elaborate and dangerous process of landing it.

A chase car is dispatched to the runway to tell the pilot how far he is from the ground; the plane has to be deliberately stalled to get it to touch down.

Taking off is also dangerous: the wings are held aloft by rolling "pogo sticks" that sometimes fail to detach when the aircraft takes flight. U-2 pilots have to dip the wings to drop them, and if they over turn, they can crash. For the dangers and rigors of flight and the skill required for it, American U-2 pilots -- fewer than 75 -- are an elite and tight fraternity.

The small fleet of U-2s has a long and storied history in the Cold War as well as an active place in the war in Iraq.

For most of its history, the U-2 has been regarded as a "strategic" platform, providing information to the president and CIA rather than battlefield commanders.

The 1991 Persian Gulf war changed that: the U-2 provided 50 percent of all imagery and 90 percent of ground-targeting imagery. The war was a watershed for the U-2, when it proved it could provide near-immediate tactically useful imagery. It was the largest U-2 operation ever, with nine aircraft and 30 pilots flying as many as five sorties a day, according to the Congressional Research Service.

The plane also played a large role in the Kosovo conflict, providing 80 percent of battlefield imagery.

The aircraft is best known from the May 1960 shoot-down of Gary Francis Powers, a CIA pilot, over the Soviet Union. Powers' mission was one of several meant to determine for President Dwight D. Eisenhower whether the Soviet Union was building more nuclear bombers than was previously known. From U-2 imagery gathered before Powers' capture and public trial, the United States determined the Soviets had merely erected a façade and there was no bomber or missile gap.

Source: United Press International

in: http://www.spacewar.com/news/Pentagon_To_Retire_U2_Spy_Plane.html

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