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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

Vorsat

Setembro 19, 2008

Vera Gomes

Tal como o nome sugere, é um satélite. O que o nome não deixa adivinhar é que se trata de um satélite português!!!! É verdade: o Vorsat é o segundo satélite português criado por alunos da Faculdade de Engenharia da Universidade do Porto com um custo aproximado de 100 mil euros.

 

Neste momento o projecto académico tem como único objectivo medir a altitude do satélite nas órbitas terrestres, mas conta já com o apoio da ESA que dará "boleia ao pequeno satélite para ser colocado em órbita.

 

Poderão ler mais sobre o assunto na Exame Informática Online, clicando aqui.

Space-based missile defense and the psychology of warfare

Setembro 09, 2008

Vera Gomes

by Taylor Dinerman
Monday, September 8, 2008

Anyone who wants to understand the way our enemies really think, as well as how and why we fail to grasp their reality should read Kevin Woods recent book The Mother of All Battles: Saddam Hussein’s Strategic Plan for the Persian Gulf War published by the Naval Institute Press. It tell the story of the 1991 Gulf War from the Iraqi point of view based largely on captured documents and published Arabic sources. The most important point in this study is that, from Saddam’s point of view, as well as that of the Ba’athist leadership, they won. After all, in spite of being ignominiously kicked out of Kuwait and having their armies thoroughly defeated on the battlefield, they remained in power. Political power was the only thing that counted and they had been able to keep it.

 

One of the keys to their belief that they won was that they were able to launch dozens of long-range missiles at their enemies, especially at Israel. They believed that the boost that this gave them, at home and in the Arab world, somehow compensated for everything that happened on the battlefield in Kuwait and southern Iraq.

 

Looking back on the German V-2 campaign against London and Antwerp, the greatest military effect was not the physical and psychological damage done to England and Belgium, but the impact on Germany’s national morale.

In his autobiography It Doesn’t Take A Hero Norman Schwarzkopf wrote that “…in essence what they had was a weapon that could fly 300 miles and miss the target by a couple of miles with a warhead of only 160 pounds. Militarily, that was the equivalent of a single airplane flying over and dropping one small bomb and flying away—terrible for anyone it happened to land on but in the grand scheme of warfare, a mosquito.

 

However the Scud was effective as a terror weapons against civilian populations.” Ever since 1991 this has been the accepted US and Western view of the missile campaign. Kevin Wood now has given us a much different view these attacks, one that has profound implications for missile defense policy and for the way that political leaders have to rethink the instructions they give to the military.

 

Looking back on the German V-2 campaign against London and Antwerp that went on from September 1944 until April 1945, the greatest military effect was not the physical and psychological damage done to England and Belgium, but the impact on Germany’s national morale. One should never forget that these were called Vengeance weapons. For a population suffering under nearly non-stop Allied bombardment and facing defeat on every front, the fact that they were in some small way able to keep hitting back with a wonder weapon that their enemies could not match was a factor keeping them fighting. Nazi propaganda did not fail to manipulate these feelings.

 

Ba’athist Iraq’s war-weary population was likewise subject to massive and—let’s face it—masterful propaganda. Hitting the hated Israelis, even with ineffective weapons, and the fact that due to US political pressure the Israelis did not strike back, was seen by Iraqis and by other Arabs as a great victory. A claim made explicit in a memoir written by Saddam’s missile force commander Hazim Abd al-Razzaq al-Ayyubi Forty-Three Missiles on the Zionist Enemy published in Amman, Jordan in 1998.

 

Al-Ayyubi described how, in the years and months leading up to the war, his two missile brigades practiced their “shoot and scoot” operational techniques. He also wrote about the very serious efforts the Iraqis made building multiple secure communications links using both radio and phone lines. According to a report to Saddam, they started the war with 230 missiles and 75 “special” warheads. Interestingly, he also bragged about the success of his deception units, not only in fooling US and Coalition targeting efforts, but also in deceiving the UN inspectors who tried to account for the missiles. Wood makes it clear “that despite the cost to the Iraqi people, Iraq’s successful violation of UNSC [United Nations Security Council] resolution 687 was a source of great pride to its leaders.”

 

Most, but not all, of what the Iraqis believed they had accomplished with their attacks was nonsense. The claims that they hit Ben Gurion Airport and the Ministry of Defense in Tel Aviv, or the Haifa Technology Institute, are just not serious. As was their claim to have been “the first Arab country to conduct effective offensive operations against the enemy (Israel).” What is true is that these attacks “fulfilled the Iraqi President’s vow that he would retaliate against Israel as revenge for their attacks against the Iraqi reactor.”

 

It is exactly this need for revenge that should get the attention of those in the US government who are trying to design a realistic missile defense policy for the next fifty years. Tyrannical regimes and terrorist movements share the need to excite people with dramatic and violent events. The more spectacular the attack, the better. Firing long-range missiles at an enemy, even if you only hit an empty parking lot, can provide followers with a level of emotional satisfaction. This in turn can motivate them to continue to fight even in a seemingly hopeless battle.

 

In future wars, those who are fighting against the West—today Iran or North Korea, tomorrow, who knows?—will use ballistic missiles not only to terrorize enemy civilian populations but to build morale among their own forces and people. Missile defense is the key to winning this critical psychological battle. As long as their missiles are being shot out of the sky, claims that they are hurting the enemy and thus filling people’s need for revenge can be shown to be utterly empty.

 

Missile defense is the key to winning this critical psychological battle. As long as their missiles are being shot out of the sky, claims that they are hurting the enemy and thus filling people’s need for revenge can be shown to be utterly empty.

This, however, cannot be done with terminal phase defense weapons. To hit a missile or a warhead that is descending towards its target may be a feat of technological skill, but it does nothing to decrease the emotional satisfaction that comes from striking a hated enemy. Midcourse interceptors such as the US GBI or the Israeli Arrow are better, but the best way to publicly humiliate those who are launching Scud-type missiles is to shoot them down as soon after they leave the launch pad as possible. The only weapon now in development that will—in theory—be able to do this is the Airborne Laser (ABL), which the Missile Defense Agency plans to test next year.

This is indeed a promising system, but it has its limits. Its range is, according to unclassified reports, about 300 kilometers, and the US only plans to build, at most, seven aircraft. If the goal is to prevent the enemy from using its missile attacks to build its own side’s morale and thus lengthen the war, another solution must be found.

 

Space-based interceptors, such as a new version of the Brilliant Pebbles program that was canceled in 1993, could, in combination with space- and ground-based sensors, knock down missiles of this type in the boost phase. Significantly, they would do so over the launching country’s own territory and at least some of the citizens would witness the destruction of their leader’s vengeance weapons. This news would spread through word of mouth. This might be one of the keys to undermining their will to make war and help shorten the conflict.

 


Alternativas de acesso ao espaço

Setembro 09, 2008

Vera Gomes

Ainda no seguimento da polémica em torno do acesso dos americanos ao espaço em geral e à ISS em particular, Taylor Dinnerman escreveu um artigo na Space Review sobre o assunto.

"Alternatives for human space access

by Taylor Dinerman
Tuesday, September 2, 2008

When President Kennedy announced that America was going to the Moon in 1961 he had a pretty good idea that the mission was doable with the decade. He was lucky that his predecessor, President Eisenhower, in spite of his skepticism towards the whole idea of a “space race”, had given the go ahead to Wernher von Braun and his team to begin work on the giant F-1 rocket engines that would power the Saturn 5. The ability to put 120 tons into low Earth orbit (LEO) in one go was an essential part of the Apollo Moon program.

 

The alternative, to slowly assemble a Moon vehicle in orbit, was rejected. Today NASA’s plan for an affordable and sustainable Moon, Mars, and beyond program relies on a new set of systems, the Ares 1 and Ares 5 launch vehicles and the Orion capsule. If these systems work as planned the US will be able to deliver substantial payloads to the lunar surface and eventually be able to shuttle astronauts and cargo back and forth.

 

Keeping the shuttle alive will cost anywhere from four to five billion dollars a year in additional spending, even if they launch only two or three times a year. Bumping NASA’s overall budget to 23 billion dollars or more may not be politically feasible.

It will take considerable time and money to develop these systems, but time may be the one thing that US politicians do not want to give the space agency. Russia’s invasion of Georgia has changed the situation and even without a future crisis it will be very hard for NASA to ask Congress to fund future Soyuz flights for US passengers to the International Space Station after the existing deal runs out in 2011.

 

Senator and presidential candidate John McCain, and others, have asked NASA and President Bush to do nothing that would jeopardize the ability of the next President to continue to fly the Shuttle until the Ares/Orion system is ready in 2015. If McCain or Barack Obama decides to take this path, it will cost anywhere from four to five billion dollars a year in additional spending, even if they launch only two or three times a year. Bumping NASA’s overall budget to 23 billion dollars or more may not be politically feasible. Getting the extra money needed to keep this option open within the next few months looks exceptionally difficult: Congress would probably have to return after the election and vote either on a supplemental budget or pass a fiscal year 2009 budget with the appropriations needed to keep building the Shuttle tanks at Michoud in Louisiana.

 

There has been speculation that the US may seek to buy transportation from China to the ISS using their Long March/Shenzhou combination. In the past this has been rejected for mostly political reasons. China’s lack of transparency about their space program is also a factor in the US reluctance to consider this alternative. Even if China has a successful first flight of its Long March 5 rocket in 2010, as currently planned, it will be take at least two or three successful manned test flights before the US would be willing to risk American lives on this vehicle.

 

The Long March 5 is intended to be a vehicle in the EELV or improved Ariane 5 class capable of putting a total of more than 25 tons into LEO. If it works this will be an impressive achievement. It is a sign of just how far China has come, this will be by far the most power launch vehicle ever built by an Asian nation.

 

There are a number of possible US alternatives, but none of them has been proven. Many in the space industry were hoping that SpaceX’s Falcon 9/Dragon capsule would be ready to compete for an as yet unannounced award for Capability D (human spaceflight) of NASA’s Commercial Orbital Transportation Services program. The failure of the Falcon 1 launch last month was a big disappointment. They apparently have plans to try again as soon as late ths month, but after three failures they have a pretty steep hill to climb to gain the credibility needed to fly US astronauts as paying passengers in 2011, which is when the system would be needed.

 

The second COTS award has now gone to Orbital Sciences Corporation, who plans to use their new Taurus 2 launcher that is supposed to make its first test flight in 2010 and a Cygnus capsule to deliver cargo to the ISS. They hope to fly their first operational mission out of Wallops Island on the Virginia coast sometime in 2012. While intended solely for cargo missions, Cygnus could perhaps be converted into a manned spacecraft.

 

An interesting alternative might be to try and fit a Dragon or Cygnus capsule atop an EELV or even a Delta 2. This would take a lot of testing and certainly a lot of investment, from the government as well as from industry. There has also been talk that the Boeing X-37 spaceplane might be adopted for this mission. The situation that the next President and Congress will face is a tough one, but if they have the right combination of guts and imagination they can take this lemon and make lemonade.

It will be pretty expensive keeping the Shuttle flying for a few more years and financing a new alternative manned space vehicle based on the COTS D program, but if the Congress refuses to buy any more seats on Soyuz the US government may not have any real choice.

As the US and its partners build a permanent Moon base they will want to have multiple ways of getting there and back. The US has a number of ways to get to its bases in Antarctica; it should be the same with the Moon. Building an alternative system based on either Dragon, Cygnus, or X-37 will provide that security. One, or maybe more, of these spacecraft and their launchers will also provide access to private space facilities such as Bigelow’s space hotel project.

 

It will be pretty expensive keeping the Shuttle flying for a few more years and financing a new alternative manned space vehicle based on the COTS D program, but if the Congress refuses to buy any more seats on Soyuz the US government may not have any real choice. They should make the best of it."

 

(artigo disponível em: http://www.thespacereview.com/article/1201/1)

Geórgia e o Espaço

Setembro 05, 2008

Vera Gomes

O Universe Today noticia que os astronautas americanos poderão abandonar a ISS em 2012 por causa da legislação americana existente que dificulta o pagamento aos russos, uma vez que a excepção existente apenas está vigente até 2011. É por isso necessário que o Congresso Americano aprove um prolongamento dessa excepção legislativa por forma a que a NASA possa pagar à Agência Espacial Russa os lugares do Soyuz.

 

O próprio Michael Griffin admite que depois do conflito na Geórgia, dificilmente o Congresso Norte-Americano irá prolongar essa autorização.

 

Para saber mais, clique aqui.

Nasa avalia possibilidade de os vaivéns poderam voar até cinco anos depois do previsto

Setembro 01, 2008

Vera Gomes

O máximo responsável da agência espacial norte-americana Nasa, Michael Griffin, solicitou um relatório para avaliar quais as opções possíveis para que os vaivéns espaciais voem até 2015, mais cinco anos do que o previsto.

 

O pedido consta de um e-mail interno da Nasa a que o jornal norte-americano Orlando Sentinel teve acesso.

 

«O Administrador (M. Griffin) pediu aos responsáveis do programa dos vaivéns, da Constellation (o programa que vai suceder aos actuais vaivéns) e do programa da Estação Espacial Internacional (ISS) para que apresentassem opções com vista a prolongar os voos dos vaivéns até 2015», escreveu John Coggeshall, director de planeamento do Centro Espacial Johnson (no Texas) no e-mail enviado quarta-feira.

 

«Queremos concentrar-nos na forma de eliminar o fosso (entre 2010 e 2015) no que diz respeito ao acesso de astronautas norte-americanos ao espaço», acrescenta Coggeshall nos excertos do seu e-mail publicados pelo Orlando Sentinel.

 

Um porta-voz da Nasa confirmou a autenticidade do e-mail, minimizando no entanto a notícia.

 

A opção de prolongar os voos dos vaivéns espaciais é «prematura», uma vez que a Nasa ainda nem concluiu os estudos para tomar essa decisão, declarou o porta-voz John Yembrick.

 

«O nosso objectivo, naturalmente, por enquanto mantém-se: deixar de utilizar os vaivém em 2010», acrescentou.

 

No entanto, os estudos pedidos por Griffin podem significar uma mudança da política espacial norte-americana, com a entrada de um novo presidente e de um novo Congresso em Janeiro de 2009.

 

Em 2004 a administração Bush decidiu retirar das missões de voo os três vaivéns a partir de 01 de Outubro de 2010, uma vez finalizada a construção da ISS, financiada em grande parte pelos Estados Unidos.

 

Os quatro mil milhões de dólares de poupança por ano que significaria esta medida permitiriam aos Estados Unidos financiar o desenvolvimento do programa Constellation, com a cápsula Orion, que deverá suceder aos vaivéns.

 

Isto sem aumentar o orçamento anual da Nasa, que se estima ser de cerca de 17 mil milhões de dólares.

A Orion não estará pronta a voar antes de 2015, o que faz com que durante cinco anos os Estados Unidos dependam exclusivamente das naves Soyouz russas para que os seus astronautas cheguem à ISS.

 

Mas as recordações da Guerra Fria, que a recente crise na Geórgia tornou bastante mais vívidas, inquietam vários congressistas norte-americanos, que dizem agora - e abertamente - que querem mais opções quanto à forma de evitar que o acesso dos astronautas americanos ao espaço entre 2011 e 2015 dependa exclusivamente da «boa-vontade» de Moscovo.

 

O senador John McCain, candidato republicano às presidenciais de Novembro, pediu na semana passada - numa carta enviada à Casa Branca - para que Bush adie em pelo menos um ano a decisão de acabar com o programa dos vaivéns espaciais, de forma a manter mais uma opção em aberto.

 

O seu rival na corrida à Casa Branca, o democrata Barack Obama, propôs recentemente aumentar o orçamento da Nasa em dois mil milhões de dólares.

 

(in Sol Online)

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