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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

Japão estabelece uma rede de satélites espiões

Fevereiro 28, 2007

Vera Gomes

After nearly a decade of trying, Japan has succeeded in establishing a network of spy satellites that can peer at any point on the globe, officials said Monday.

The successful launch Saturday of the last of a fleet of four reconnaissance satellites significantly boosts Japan's ability to gather independent intelligence and re-establishes Tokyo as a major player in Asia's accelerating space race.

Previously, Japan had to rely more heavily on its main ally, the United States, for spy satellite data.

“I welcome the success of the launch, and I hope Japan's space program will mark results that are appropriate for a leading nation in space,'' said Prime Minister Shinzo Abe, in a statement. The satellite lifted off aboard an H-2A rocket from the remote island of Tanegashima.

Japan started its spy satellite program in 1998 after North Korea launched a missile over the country's main island. The Japanese program has been plagued by delays and setbacks -- including a spectacular mid-air explosion three years ago and problems with optics aboard the probes.

But officials said Monday the latest satellite had attained its orbit and was functioning without problems. A prototype for future more advanced probes was also launched aboard the rocket.

“The satellite will undergo a three-month test period,'' said Yasuhiro Itakura of the Cabinet office in charge of the program. “But it is functioning fine so far.''

The launch, which was delayed three times because of bad weather, reaffirms Japan as one of Asia's top space powers. Officials stress the Japanese-designed-and-built H-2A rocket has a better than 90 percent success rate in its 12 launches to date, which is comparable to other advanced countries.

Tokyo needed the boost.

In November 2003, Japan's second spy satellite was aborted and the spacecraft exploded in a fireball. A short time later, China put its first astronauts in orbit, establishing itself as the leader in Asia's push into space.

Last month, China blasted a satellite out of orbit with a ground-based missile and last week, Pakistan tested one of its most advanced long-range missiles. India's rocket development efforts are also rapidly advancing.

These military programs have influenced Japan's goals in space.

Japan has limited its space program to non-military uses since 1969. Late last year, the ruling party proposed the military be allowed to mount space missions, as long as they were for defensive purposes.

Japan, following China's lead, is also mulling the possibility of launching manned space flights. It has yet to send astronauts into space, though Japanese crew members have flown aboard U.S. Space Shuttle flights.

“With China planning a moon mission and rapidly improving its space program, Japan is at a crucial stage,'' The Nikkei, a major business daily, said in an editorial. “We must continue to have successful launches.''

Japan's spy satellites have been slammed by critics as inadequate -- the quality of the photos they provide is far worse than their U.S. counterparts.

The improved version isn't due for launch until 2009, after the first two satellites complete their planned five-year lifespan.


in: Japan establish Spy Satellite Network

Detritos Espaciais - um problema cada vez maior

Fevereiro 22, 2007

Vera Gomes

(do sítio do Boletim Em Órbita)

"Um estágio superior Breeze-M explodiu em órbita terrestre criando mais de
1000 detritos espaciais.

A 28 de Fevereiro de 2006 o foguetão 8K82KM Proton-M/Breeze-M (53511/88515)
era lançado desde o Complexo LC200 PU-39 do Cosmódromo GIK-5 Baikonur,
Cazaquistão, transportano o satélite Badr-1 (Arabsat-4A) a bordo. Os três
estágios do foguetão lançador desempenharam a sua função sem qualquer
problema, mas a queima do estágio superior Breeze-M (88515) não correu como
previsto deixando o satélite numa órbita inútil. Após considerações iniciais
acerca de planos para salvar o satélite de comunicações utilizando a
gravidade lunar, foi decidido abandonar o Badr-1 e este acabou por reentrar
na atmosfera. Entretanto o estágio Breeze-M (88515) permaneceu em órbita com
os tanques quase cheiros de propolentes hipergólicos.

Os propolentes hipergólicos são altamente tóxicos e corrosivos, entrando em
ignição quando em contacto, não necessitando de um oxidante como o oxigénio
líquido. As membranas de isolamento que se encontram nas condutas dos
propolentes acabaram por sofrer os efeitos da corrosão devido à exposição
prolongada aos mesmos em órbita, levando a que entranssem em contacto e à
posterior explosão do veículo.

No dia 19 de Fevereiro, astrónomos amadores na Austrália detectaram uma
brilhante explosão em órbita que se assemelhava à combustão de um veículo no
espaço. Inicialmente era desconhecida a causa deste fenómeno, mas análises
posteriores levaram à determinação de que se tratava da mesma órbita onde se
encontrava o estágio Breeze-M (88515). Outras hipóteses sugeriram que o
veículo tería sido atingido por um micrometeoro, mas a explicação mais
lógica parece sugerir uma falha no mesmo relacionada com os seu propolente
(situação já anteriormente verificada em órbita com outros estágios
superiores).

O Comando Espacial norte-americano já detectou 1111 detritos em órbita.
Tendo em conta que somente os detritos superiores a 10 cm são detectados,
então pode-se concluir que o resultado da explosão será muito maior. O
número de detritos detectados será superior aos que resultaram da destruição
do satélite meteorolígico chinês Feng Yun-1C durante um teste anti-míssil no
passado mês de Janeiro.

A órbita dos detritos irá eventualmente fazer com que estes acabem por
reentrar na atmosfera, mas devido à sua altitude ainda deverão permanecer em
torno da Terra durante algum tempo."

Space Security Index

Fevereiro 19, 2007

Vera Gomes

No site Space Security Index pode-se encontrar vários textos acerca variadas facetas da segurança espacial. Áreas como Leis e Doutrina Espaciais, Programas Civis e Utilidades Globais e Protecção de Sistemas Espaciais, são alguns exemplos de abordagens que se podem encontrar neste site. Anualmente é publicado neste a publicação Space Security que aborda as já mencionadas áreas, entre outras, com base na opinião dos diversos estudiosos deste tema de investigação.

Programa espacial turco: um modelo para potências regionais emergentes

Fevereiro 12, 2007

Vera Gomes

"Turkey’s military satellite program: a model for emerging regional powers"
by Taylor Dinerman
Tuesday, January 2, 2007

Turkey’s air force is planning to spend at least $200 million to buy and launch an electro-optical reconnaissance satellite with a resolution of 80 centimeters. They hope to have it in orbit and operational by 2011. They are apparently not going to impose the onerous “local content requirements” that have recently bedeviled so many Turkish military procurement programs. This suggests that this is being treated as a priority and the Turkish military is not going to allow local industrial politics to get in the way of their need for broad, persistent, and sovereign regional observation.
As a NATO member Turkey has some access to information from US satellites, and they can also buy imagery on the open market from Spot Image, DigitalGlobe, or others. In spite of this, they want to have their own satellite and later they will surely want to have an all-weather radar imaging system and multi- and hyperspectral capability. Turkey is in a geopolitically rough neighborhood, and their need to be able to keep track of what is happening throughout the region is all too obvious. Space-based observation is one important way that they can keep track of activities in places like Armenia, Iraq, or the Aegean Sea, where Turkey’s national security interests are at stake.
For $200 million Turkey may be able to buy a satellite with the resolution they want. However, it may not work as well as expected, because for that price they cannot expect to buy sophisticated pointing, maneuvering, and field-of-view technology. Effective space-based reconnaissance, even for a medium-sized power, depends on a minimum level of space situational awareness. Not only do they need to know exactly where their satellite is at all times, they need to also be able to precisely control where its sensors are pointing.
There is also the problem of communicating with the satellite. Imagery requires a lot of bandwidth: the bigger the antenna and the more powerful the transmitter, the easier it will be for the Turks to download the data. This adds to the system’s complexity and expense, and also requires one or more large ground stations. Since they will be using it for regional monitoring they do not need the expensive relay systems used by the US and other global powers. They may find, though, that it will be difficult to gather timely imagery from places like Afghanistan or Central Asia, where Turkey has significant interests.
Turksat, a government-owned civilian corporation, owns and operates three Alcatel-built satellites (with a fourth under construction) that provide direct broadcast and other communications services to Turkey and Central Asia. This has given the Turkic-speaking peoples of that geopolitically sensitive region access to the Turkish media and helps Ankara compete for cultural, economic, and political influence against the other major regional powers such as Russia, Iran, Pakistan, India, and China. The military reconnaissance program, as currently defined, will probably not give their government much, if any, information from these countries, but will instead concentrate on taking pictures of nations that directly border on Turkey.
More and more nations understand that the one place from which they can legitimately spy on their neighbors is low Earth orbit (LEO) and they rarely hesitate to do so. No nation in a zone of conflict—or potential conflict—can escape the need for situational awareness, and only observation satellites supply that need. From this fact two things follow. One is that without a highly trained and experienced team of imagery interpreters an expensive satellite’s information is useless. Any nation that buys a satellite without insuring that it has at least as much money to spend on people as it does on hardware is wasting its money and probably deluding itself as well.
For the last four years Turkey has been sending a number of experts to the European Union Satellite Centre in Torrejon, Spain. There they received training in satellite imagery interpretation and management. By the time the first Turkish imaging satellite is launched in 2011 Turkey will have a good-sized cadre of experts. Since Turkey is already buying imagery from commercial sources, they are building the imagery archive that is indispensable for any nation that wants to make real use of satellite reconnaissance. This program is obviously pragmatic and well thought out. The prestige of owning such a spacecraft is a minor consideration compared to the overall practical need for information.
A second issue that a nation such as Turkey has to take into account is that, with more and more observation satellites up there, nations and organizations will find themselves making ever greater efforts to hide their activities underground or under the anti-satellite surveillance systems know as “roofs”. This limitation does not mean that satellites are useless: the same problem existed when the only eyes in the sky were propeller-driven aircraft with “wet” film cameras. It does mean that satellites, and the men and women who examine their pictures, are going to be engaged in an eternal game of hide-and-seek. All-weather radar imagery and multi- and hyperspectral data will help to defeat some types of camouflage, but for Turkey to think that a satellite by itself provides them with a sure and reliable source of information on their region is to open the door to dangerous surprises.
The bright hopes of the early 1990s that Turkey would be able to provide a bridge between the newly independent nations of Central Asia and the West have long since evaporated. The neighborhood from the Balkans through to Chinese Turkistan and, of course, Iraq is over-endowed with angry, violent, and well-armed groups and governments. Turkey’s armed forces are engaged in a low-level war against the terrorist PKK, they are committed on a small scale to the NATO force in Afghanistan and have to cope with dangerous dictatorships in Syria and Iran as well as with the complex struggles ongoing in the Caucasus.
Under these strategic circumstances, Turkey’s decision to acquire an independent satellite surveillance capability is a wise one. They do not intend to waste their resources on a techno-nationalist prestige program: the situation is too serious for that. Someday, no doubt, the Turks will be able to build their own satellites. For the moment they are using the “smart buyer” approach. If they stay on this track they will be a model for other medium-sized nations who need the regional situational awareness that only a LEO-based spacecraft can provide.
________________________________________
Taylor Dinerman is an author and journalist based in New York City.

ESA desenvolve sofisticada ferramenta de meteorologia espacial

Fevereiro 05, 2007

Vera Gomes

Uma ferramenta sofisticada, em desenvolvimento no ESOC, promete fornecer meios eficazes de monitorização e previsão, de modo a prevenir que os sistemas electrónicos de bordo se despedacem, os instrumentos científicos se danifiquem e o satélite se perca de vez, devido a partículas de elevada energia ou outros fenómenos de meteorologia espacial.

De acordo com a ESA, a actividade solar influencia todo o sistema solar de várias formas, incluindo a geração de correntes de partículas energéticas que se movem rapidamente e explosões repentinas de raios X perigosos durante as chamas solares. Os raios cósmicos energéticos de qualquer outro ponto na galáxia penetram também no nosso sistema solar. Estes fenómenos estão entre as principais causas do comportamento anormal e do envelhecimento dos satélites e dos seus sensíveis instrumentos científicos.

Mas desde inícios de 2005, o SEISOP (Sistema de Informação sobre o Ambiente Espacial para Operações) – ferramenta de monitorização e previsão da meteorologia espacial, em desenvolvimento no Centro de Operações Espaciais da ESA – tem vindo a oferecer, com sucesso, relatórios quase em tempo real ao Integral, o observatório espacial de raios gama da ESA.

Como informa a ESA, o SEISOP, desenvolvido em colaboração com o Projecto Piloto de Aplicações de Meteorologia Espacial da ESA com financiamento da portuguesa Task Force ESA/ Portugal, inclui uma base de dados dos registos do estado dos satélites e das observações meteorológicas espaciais a nível mundial, juntamente com sofisticadas aplicações de software que fornecem relatórios, avisos, previsões e um rastreio histórico para a Equipa de Controlo de Voo do Integral.

"A meteorologia espacial afecta os satélites de várias formas. Podem dar-se perdas aleatórias de dados, alterações na dinâmica da órbita e uma redução da qualidade de dados científicos. Por isso, as actualizações em tempo real são essenciais na altura de decidir quanto tempo se devem desligar os instrumentos durante períodos de risco," afirma Alessandro Donati, responsável pelo Gabinete de Tecnologias e Conceitos Avançados de Missões, sedeado no ESOC.

O SEISOP, membro da Rede Europeia de Meteorologia Espacial (SWENET), permite aos controladores da missão preverem quando devem desligar instrumentos como star trackers, colocar os sistemas no 'modo de segurança' ou tomar outras medidas para proteger os sensíveis componentes electrónicos e os sensores científicos a bordo.

Enquanto que alguns instrumentos estão equipados para se desligarem automaticamente durante períodos adversos, nem todos eles estão, e reactivar um instrumento após uma paragem automática requer bastante tempo. Além disso, e ainda segundo a ESA, até hoje tem sido difícil saber quando a radiação desce a níveis seguros, depois de se dar um fenómeno particular, como por exemplo uma chama solar.

No decorrer deste ano, o SEISOP passará por um desenvolvimento operacional com vista a fornecer a todas as missões da ESA as mesmas actualizações vitais de meteorologia espacial. Alessandro Donati e a restante equipa espera começar a trabalhar este ano para criar a versão operacional final. Estes responsáveis salientam que “o SEISOP pode potencialmente fornecer serviços de aviso não só para a ESA mas também para agências espaciais em todo o mundo, uma vez que a meteorologia espacial pode afectar qualquer satélite".

in: http://www.cienciapt.net/noticiasdesc.asp?id=14501

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