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NASA Researchers Studying Advanced Nuclear Rocket Technologies
January 9, 2013
By using an innovative test facility at NASA’s Marshall Space Flight Center in Huntsville, Ala., researchers are able to use non-nuclear materials to simulate nuclear thermal rocket fuels - ones capable of propelling bold new exploration missions to the Red Planet and beyond. The Nuclear Cryogenic Propulsion Stage team is tackling a three-year project to demonstrate the viability of nuclear propulsion system technologies. A nuclear rocket engine uses a nuclear reactor to heat hydrogen to very high temperatures, which expands through a nozzle to generate thrust. Nuclear rocket engines generate higher thrust and are more than twice as efficient as conventional chemical rocket engines.
The team recently used Marshall’s Nuclear Thermal Rocket Element Environmental Simulator, or NTREES, to perform realistic, non-nuclear testing of various materials for nuclear thermal rocket fuel elements. In an actual reactor, the fuel elements would contain uranium, but no radioactive materials are used during the NTREES tests. Among the fuel options are a graphite composite and a “cermet” composite - a blend of ceramics and metals. Both materials were investigated in previous NASA and U.S. Department of Energy research efforts.
Nuclear-powered rocket concepts are not new; the United States conducted studies and significant ground testing from 1955 to 1973 to determine the viability of nuclear propulsion systems, but ceased testing when plans for a crewed Mars mission were deferred.
The NTREES facility is designed to test fuel elements and materials in hot flowing hydrogen, reaching pressures up to 1,000 pounds per square inch and temperatures of nearly 5,000 degrees Fahrenheit - conditions that simulate space-based nuclear propulsion systems to provide baseline data critical to the research team.
“This is vital testing, helping us reduce risks and costs associated with advanced propulsion technologies and ensuring excellent performance and results as we progress toward further system development and testing,” said Mike Houts, project manager for nuclear systems at Marshall.
A first-generation nuclear cryogenic propulsion system could propel human explorers to Mars more efficiently than conventional spacecraft, reducing crews’ exposure to harmful space radiation and other effects of long-term space missions. It could also transport heavy cargo and science payloads. Further development and use of a first-generation nuclear system could also provide the foundation for developing extremely advanced propulsion technologies and systems in the future - ones that could take human crews even farther into the solar system.
Building on previous, successful research and using the NTREES facility, NASA can safely and thoroughly test simulated nuclear fuel elements of various sizes, providing important test data to support the design of a future Nuclear Cryogenic Propulsion Stage. A nuclear cryogenic upper stage - its liquid- hydrogen propellant chilled to super-cold temperatures for launch - would be designed to be safe during all mission phases and would not be started until the spacecraft had reached a safe orbit and was ready to begin its journey to a distant destination. Prior to startup in a safe orbit, the nuclear system would be cold, with no fission products generated from nuclear operations, and with radiation below significant levels.
“The information we gain using this test facility will permit engineers to design rugged, efficient fuel elements and nuclear propulsion systems,” said NASA researcher Bill Emrich, who manages the NTREES facility at Marshall. “It’s our hope that it will enable us to develop a reliable, cost-effective nuclear rocket engine in the not-too-distant future."
The Nuclear Cryogenic Propulsion Stage project is part of the Advanced Exploration Systems program, which is managed by NASA’s Human Exploration and Operations Mission Directorate and includes participation by the U.S. Department of Energy. The program, which focuses on crew safety and mission operations in deep space, seeks to pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future vehicle development and human missions beyond Earth orbit.
Marshall researchers are partnering on the project with NASA’s Glenn Research Center in Cleveland, Ohio; NASA’s Johnson Space Center in Houston; Idaho National Laboratory in Idaho Falls; Los Alamos National Laboratory in Los Alamos, N.M.; and Oak Ridge National Laboratory in Oak Ridge, Tenn.
The Marshall Center leads development of the Space Launch System for NASA. The Science & Technology Office at Marshall strives to apply advanced concepts and capabilities to the research, development and management of a broad spectrum of NASA programs, projects and activities that fall at the very intersection of science and exploration, where every discovery and achievement furthers scientific knowledge and understanding, and supports the agency’s ambitious mission to expand humanity’s reach across the solar system. The NTREES test facility is just one of numerous cutting-edge space propulsion and science research facilities housed in the state-of- the-art Propulsion Research & Development Laboratory at Marshall, contributing to development of the Space Launch System and a variety of other NASA programs and missions.
Available in: http://www.nasa.gov
“Nuclear-powered rocket concepts are not new.”
Choose the alternative in which the extract is in the same verb tense as the one above.
NASA Researchers Studying Advanced Nuclear Rocket Technologies
January 9, 2013
By using an innovative test facility at NASA’s Marshall Space Flight Center in Huntsville, Ala., researchers are able to use non-nuclear materials to simulate nuclear thermal rocket fuels - ones capable of propelling bold new exploration missions to the Red Planet and beyond. The Nuclear Cryogenic Propulsion Stage team is tackling a three-year project to demonstrate the viability of nuclear propulsion system technologies. A nuclear rocket engine uses a nuclear reactor to heat hydrogen to very high temperatures, which expands through a nozzle to generate thrust. Nuclear rocket engines generate higher thrust and are more than twice as efficient as conventional chemical rocket engines.
The team recently used Marshall’s Nuclear Thermal Rocket Element Environmental Simulator, or NTREES, to perform realistic, non-nuclear testing of various materials for nuclear thermal rocket fuel elements. In an actual reactor, the fuel elements would contain uranium, but no radioactive materials are used during the NTREES tests. Among the fuel options are a graphite composite and a “cermet” composite - a blend of ceramics and metals. Both materials were investigated in previous NASA and U.S. Department of Energy research efforts.
Nuclear-powered rocket concepts are not new; the United States conducted studies and significant ground testing from 1955 to 1973 to determine the viability of nuclear propulsion systems, but ceased testing when plans for a crewed Mars mission were deferred.
The NTREES facility is designed to test fuel elements and materials in hot flowing hydrogen, reaching pressures up to 1,000 pounds per square inch and temperatures of nearly 5,000 degrees Fahrenheit - conditions that simulate space-based nuclear propulsion systems to provide baseline data critical to the research team.
“This is vital testing, helping us reduce risks and costs associated with advanced propulsion technologies and ensuring excellent performance and results as we progress toward further system development and testing,” said Mike Houts, project manager for nuclear systems at Marshall.
A first-generation nuclear cryogenic propulsion system could propel human explorers to Mars more efficiently than conventional spacecraft, reducing crews’ exposure to harmful space radiation and other effects of long-term space missions. It could also transport heavy cargo and science payloads. Further development and use of a first-generation nuclear system could also provide the foundation for developing extremely advanced propulsion technologies and systems in the future - ones that could take human crews even farther into the solar system.
Building on previous, successful research and using the NTREES facility, NASA can safely and thoroughly test simulated nuclear fuel elements of various sizes, providing important test data to support the design of a future Nuclear Cryogenic Propulsion Stage. A nuclear cryogenic upper stage - its liquid- hydrogen propellant chilled to super-cold temperatures for launch - would be designed to be safe during all mission phases and would not be started until the spacecraft had reached a safe orbit and was ready to begin its journey to a distant destination. Prior to startup in a safe orbit, the nuclear system would be cold, with no fission products generated from nuclear operations, and with radiation below significant levels.
“The information we gain using this test facility will permit engineers to design rugged, efficient fuel elements and nuclear propulsion systems,” said NASA researcher Bill Emrich, who manages the NTREES facility at Marshall. “It’s our hope that it will enable us to develop a reliable, cost-effective nuclear rocket engine in the not-too-distant future."
The Nuclear Cryogenic Propulsion Stage project is part of the Advanced Exploration Systems program, which is managed by NASA’s Human Exploration and Operations Mission Directorate and includes participation by the U.S. Department of Energy. The program, which focuses on crew safety and mission operations in deep space, seeks to pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future vehicle development and human missions beyond Earth orbit.
Marshall researchers are partnering on the project with NASA’s Glenn Research Center in Cleveland, Ohio; NASA’s Johnson Space Center in Houston; Idaho National Laboratory in Idaho Falls; Los Alamos National Laboratory in Los Alamos, N.M.; and Oak Ridge National Laboratory in Oak Ridge, Tenn.
The Marshall Center leads development of the Space Launch System for NASA. The Science & Technology Office at Marshall strives to apply advanced concepts and capabilities to the research, development and management of a broad spectrum of NASA programs, projects and activities that fall at the very intersection of science and exploration, where every discovery and achievement furthers scientific knowledge and understanding, and supports the agency’s ambitious mission to expand humanity’s reach across the solar system. The NTREES test facility is just one of numerous cutting-edge space propulsion and science research facilities housed in the state-of- the-art Propulsion Research & Development Laboratory at Marshall, contributing to development of the Space Launch System and a variety of other NASA programs and missions.
Available in: http://www.nasa.gov
“The program, which focuses on crew safety and mission operations in deep space, seeks to pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future vehicle development and human missions beyond Earth orbit.”
Choose the alternative that presents the words that best substitutes, respectively, the bold and underlined ones in the sentences above
NASA Researchers Studying Advanced Nuclear Rocket Technologies
January 9, 2013
By using an innovative test facility at NASA’s Marshall Space Flight Center in Huntsville, Ala., researchers are able to use non-nuclear materials to simulate nuclear thermal rocket fuels - ones capable of propelling bold new exploration missions to the Red Planet and beyond. The Nuclear Cryogenic Propulsion Stage team is tackling a three-year project to demonstrate the viability of nuclear propulsion system technologies. A nuclear rocket engine uses a nuclear reactor to heat hydrogen to very high temperatures, which expands through a nozzle to generate thrust. Nuclear rocket engines generate higher thrust and are more than twice as efficient as conventional chemical rocket engines.
The team recently used Marshall’s Nuclear Thermal Rocket Element Environmental Simulator, or NTREES, to perform realistic, non-nuclear testing of various materials for nuclear thermal rocket fuel elements. In an actual reactor, the fuel elements would contain uranium, but no radioactive materials are used during the NTREES tests. Among the fuel options are a graphite composite and a “cermet” composite - a blend of ceramics and metals. Both materials were investigated in previous NASA and U.S. Department of Energy research efforts.
Nuclear-powered rocket concepts are not new; the United States conducted studies and significant ground testing from 1955 to 1973 to determine the viability of nuclear propulsion systems, but ceased testing when plans for a crewed Mars mission were deferred.
The NTREES facility is designed to test fuel elements and materials in hot flowing hydrogen, reaching pressures up to 1,000 pounds per square inch and temperatures of nearly 5,000 degrees Fahrenheit - conditions that simulate space-based nuclear propulsion systems to provide baseline data critical to the research team.
“This is vital testing, helping us reduce risks and costs associated with advanced propulsion technologies and ensuring excellent performance and results as we progress toward further system development and testing,” said Mike Houts, project manager for nuclear systems at Marshall.
A first-generation nuclear cryogenic propulsion system could propel human explorers to Mars more efficiently than conventional spacecraft, reducing crews’ exposure to harmful space radiation and other effects of long-term space missions. It could also transport heavy cargo and science payloads. Further development and use of a first-generation nuclear system could also provide the foundation for developing extremely advanced propulsion technologies and systems in the future - ones that could take human crews even farther into the solar system.
Building on previous, successful research and using the NTREES facility, NASA can safely and thoroughly test simulated nuclear fuel elements of various sizes, providing important test data to support the design of a future Nuclear Cryogenic Propulsion Stage. A nuclear cryogenic upper stage - its liquid- hydrogen propellant chilled to super-cold temperatures for launch - would be designed to be safe during all mission phases and would not be started until the spacecraft had reached a safe orbit and was ready to begin its journey to a distant destination. Prior to startup in a safe orbit, the nuclear system would be cold, with no fission products generated from nuclear operations, and with radiation below significant levels.
“The information we gain using this test facility will permit engineers to design rugged, efficient fuel elements and nuclear propulsion systems,” said NASA researcher Bill Emrich, who manages the NTREES facility at Marshall. “It’s our hope that it will enable us to develop a reliable, cost-effective nuclear rocket engine in the not-too-distant future."
The Nuclear Cryogenic Propulsion Stage project is part of the Advanced Exploration Systems program, which is managed by NASA’s Human Exploration and Operations Mission Directorate and includes participation by the U.S. Department of Energy. The program, which focuses on crew safety and mission operations in deep space, seeks to pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future vehicle development and human missions beyond Earth orbit.
Marshall researchers are partnering on the project with NASA’s Glenn Research Center in Cleveland, Ohio; NASA’s Johnson Space Center in Houston; Idaho National Laboratory in Idaho Falls; Los Alamos National Laboratory in Los Alamos, N.M.; and Oak Ridge National Laboratory in Oak Ridge, Tenn.
The Marshall Center leads development of the Space Launch System for NASA. The Science & Technology Office at Marshall strives to apply advanced concepts and capabilities to the research, development and management of a broad spectrum of NASA programs, projects and activities that fall at the very intersection of science and exploration, where every discovery and achievement furthers scientific knowledge and understanding, and supports the agency’s ambitious mission to expand humanity’s reach across the solar system. The NTREES test facility is just one of numerous cutting-edge space propulsion and science research facilities housed in the state-of- the-art Propulsion Research & Development Laboratory at Marshall, contributing to development of the Space Launch System and a variety of other NASA programs and missions.
Available in: http://www.nasa.gov
NASA Researchers Studying Advanced Nuclear Rocket Technologies
January 9, 2013
By using an innovative test facility at NASA’s Marshall Space Flight Center in Huntsville, Ala., researchers are able to use non-nuclear materials to simulate nuclear thermal rocket fuels - ones capable of propelling bold new exploration missions to the Red Planet and beyond. The Nuclear Cryogenic Propulsion Stage team is tackling a three-year project to demonstrate the viability of nuclear propulsion system technologies. A nuclear rocket engine uses a nuclear reactor to heat hydrogen to very high temperatures, which expands through a nozzle to generate thrust. Nuclear rocket engines generate higher thrust and are more than twice as efficient as conventional chemical rocket engines.
The team recently used Marshall’s Nuclear Thermal Rocket Element Environmental Simulator, or NTREES, to perform realistic, non-nuclear testing of various materials for nuclear thermal rocket fuel elements. In an actual reactor, the fuel elements would contain uranium, but no radioactive materials are used during the NTREES tests. Among the fuel options are a graphite composite and a “cermet” composite - a blend of ceramics and metals. Both materials were investigated in previous NASA and U.S. Department of Energy research efforts.
Nuclear-powered rocket concepts are not new; the United States conducted studies and significant ground testing from 1955 to 1973 to determine the viability of nuclear propulsion systems, but ceased testing when plans for a crewed Mars mission were deferred.
The NTREES facility is designed to test fuel elements and materials in hot flowing hydrogen, reaching pressures up to 1,000 pounds per square inch and temperatures of nearly 5,000 degrees Fahrenheit - conditions that simulate space-based nuclear propulsion systems to provide baseline data critical to the research team.
“This is vital testing, helping us reduce risks and costs associated with advanced propulsion technologies and ensuring excellent performance and results as we progress toward further system development and testing,” said Mike Houts, project manager for nuclear systems at Marshall.
A first-generation nuclear cryogenic propulsion system could propel human explorers to Mars more efficiently than conventional spacecraft, reducing crews’ exposure to harmful space radiation and other effects of long-term space missions. It could also transport heavy cargo and science payloads. Further development and use of a first-generation nuclear system could also provide the foundation for developing extremely advanced propulsion technologies and systems in the future - ones that could take human crews even farther into the solar system.
Building on previous, successful research and using the NTREES facility, NASA can safely and thoroughly test simulated nuclear fuel elements of various sizes, providing important test data to support the design of a future Nuclear Cryogenic Propulsion Stage. A nuclear cryogenic upper stage - its liquid- hydrogen propellant chilled to super-cold temperatures for launch - would be designed to be safe during all mission phases and would not be started until the spacecraft had reached a safe orbit and was ready to begin its journey to a distant destination. Prior to startup in a safe orbit, the nuclear system would be cold, with no fission products generated from nuclear operations, and with radiation below significant levels.
“The information we gain using this test facility will permit engineers to design rugged, efficient fuel elements and nuclear propulsion systems,” said NASA researcher Bill Emrich, who manages the NTREES facility at Marshall. “It’s our hope that it will enable us to develop a reliable, cost-effective nuclear rocket engine in the not-too-distant future."
The Nuclear Cryogenic Propulsion Stage project is part of the Advanced Exploration Systems program, which is managed by NASA’s Human Exploration and Operations Mission Directorate and includes participation by the U.S. Department of Energy. The program, which focuses on crew safety and mission operations in deep space, seeks to pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future vehicle development and human missions beyond Earth orbit.
Marshall researchers are partnering on the project with NASA’s Glenn Research Center in Cleveland, Ohio; NASA’s Johnson Space Center in Houston; Idaho National Laboratory in Idaho Falls; Los Alamos National Laboratory in Los Alamos, N.M.; and Oak Ridge National Laboratory in Oak Ridge, Tenn.
The Marshall Center leads development of the Space Launch System for NASA. The Science & Technology Office at Marshall strives to apply advanced concepts and capabilities to the research, development and management of a broad spectrum of NASA programs, projects and activities that fall at the very intersection of science and exploration, where every discovery and achievement furthers scientific knowledge and understanding, and supports the agency’s ambitious mission to expand humanity’s reach across the solar system. The NTREES test facility is just one of numerous cutting-edge space propulsion and science research facilities housed in the state-of- the-art Propulsion Research & Development Laboratory at Marshall, contributing to development of the Space Launch System and a variety of other NASA programs and missions.
Available in: http://www.nasa.gov
I. Engines powered by expanded hydrogen work better than regular chemical engines.
II. A CERMET composite is made of ceramics, metal and graphite.
III. The Nuclear Cryogenic Propulsion Stage created the technology that took human crews to Mars.
According to the text, the correct assertion(s) is(are)
O Nervo trigêmio, _____ par dos nervos cranianos, possui duas raízes, uma _________ e outra sensitiva, sendo esta com _____ divisões. A divisão __________ deixa o crânio pelo forame oval.
A candidose é a patologia __________ mais comum no homem. Conhecida também como ________, pode ser desencadeada pela exposição a ____________________ ou em pacientes _______________.
O ph ________, propicia a dissolução do esmalte. Este processo conhecido por ___________ é causado principalmente pelo ___________ que produz a fermentação da ____________.
I. Quando ele __________ os quadros, nós iremos à galeria.
II. Se eles se __________, o filho não estaria com tantos problemas na escola.
III. Vou estudar para que eu não __________ de ajuda.
Você reconhece quem teve uma festa de criança em casa no dia anterior. Alguma coisa no rosto. A expressão de quem chegou à terrível conclusão de que Herodes talvez tivesse razão.
- Que respiração ofegante o senhor tem!
- Foi de tanto encher balão.
- Que dificuldade o senhor tem para caminhar!
- Foi de tanto levar canelada tentando apartar briga.
- Como suas mãos estão trêmulas!
- Foi de tanto me controlar para não esgoelar ninguém!
Respeito e consideração para quem teve uma festa de criança em casa no dia anterior.
O pai e a mãe estão atirados num sofá, um para cada lado. Semiconscientes. Já é noite, mas a festa ainda não acabou. Sobram três crianças que não param de correr pela casa.
- Tenho uma ideia - diz o pai.
- Qual é?
- Vamos mandar eles brincarem no meio da rua. Esta hora tem bastante movimento.
- Não seja malvado. Daqui a pouco eles vão embora.
- Quando? Essas três foram as primeiras a chegar. Acho que os pais deixaram elas aqui e fugiram para o exterior.
Uma menina cruza a sala na corrida. Quando chegou, tinha o vestido mais engomado da festa. Depois de três banhos de guaraná e uma batalha de brigadeiro, parece uma veterana das trincheiras.
- Essa aí é a pior - diz o pai, num sussurro dramático.
- Essa baixinha! É um terror!
- Coitadinha. É a Cândida.
- Cândida?! É uma terrorista!
- Sshhh. - De onde é que saiu essa figura?
- É uma colega do Paulinho.
- E aquele ranhento que não para de comer?
- É o Chico. Também é colega.
- Será que não alimentam ele em casa? E o outro, o que está pulando de cima da mesa?
- É o Paulinho! Você não reconhece o seu próprio filho?
- Ele está coberto de chocolate.
- É que ele teve uma luta de brigadeiros com a Cândida...
- E perdeu, claro. A Cândida é imbatível. Guerra de brigadeiros, jiu-jítsu, vôlei com balão, hipismo com cachorro. Ela foi a única que conseguiu montar no Atlas.
- Por falar nisso, onde é que anda o Atlas?
- Fugiu de casa, lógico. Era o que eu devia ter feito.
- Ora, é só uma vez por ano...
- Você precisava me lembrar? Pensar que daqui a um ano tem outra...
- Você não pode falar. Você também gosta de fazer festa no seu aniversário.
- Mas nós somos finos. Nenhuma festa teve guerra de chocolate. Nos embebedamos como pessoas civilizadas.
- Ah é? E o anão com o trombone?
- Ah, não? A Araci é que sabe dessa história. Só que ela foi embora no mesmo dia. O Chico se aproxima.
- Tem mais cachorro, quente?
- Não, meu filho. Acabou. - Brigadeiro?
- Também acabou, Chico.
- Dá uma lambida na cabeça do Paulinho
- sugere o pai, sob um olhar de reprimenda da mãe. - Puxa, não tem mais nada?
- diz Chico. E se afasta, desconsolado.
- E ainda reclama, o filho da mãe!
- Shhh.
- Bom, você eu não sei, mas eu...
- Você o quê? - Vou tomar meu banho, se é que ainda tenho forças para ligar um chuveiro, e ver televisão na cama.
- E quando chegarem os pais? - Que pais?
- Os pais da Cândida e dos outros, ora.
- O que é que eu tenho com eles?
- Quando eles chegarem, você tem que receber. - Ah, não.
- Ah, sim!
- Mais essa?
Batem na porta. O pai vai abrir, esbravejando sem palavras. É um casal que se identifica como os pais da Cândida.
- Entrem, entrem.
- Entrem, entrem. - Nós só viemos buscar a...
- Não, entrem. A Cândida não vai querer sair agora. Ela é um encanto. Meu bem, os pais da Cândida. Sentem, sentem.
O pai esfrega as mãos, subitamente reanimado.
- Quem sabe uma cervejinha? Querida, vá buscar.
Como Araci se foi, a própria mãe - que se ocupou com a festa desde de manhã cedo, que mal se aguenta em pé, que podia matar o marido - vai buscar a cerveja. Pisando nos embrulhos de doces, nos copos de papelão e nos balões estourados que cobrem o chão e que ela mesma terá que limpar no dia seguinte. Respeito e comiseração para as mães que tiveram festa de criança em casa, no dia seguinte.
Enquanto isso o pai acaba de abrir a porta para os pais do Chico e os manda entrar, entusiasmado com a ideia de começar sua própria festa.
- Querida, mais cerveja!
Luis Fernando Veríssimo. In: comédias da vida privada - 101
crônicas escolhidas. P. 223-225.