Dear Students TF - 3o. Ano 2007,
Confira aqui o nosso Provão de Inglês - do 4o. bim./2007
Searching for Life in Other Solar Systems
Life remains a phenomenon we know only on Earth. But an innovative telescope in space could change that by detecting signs of life on planets orbiting other stars.
The search for extraterrestrial life can now be extended to planets outside our solar system. After years of looking, astronomers have turned up evidence of giant planets orbiting several distant stars similar to our sun. Smaller planets around these and other stars may have evolved living organisms. (…)
Pictures sharp enough to display geologic features of planets around other stars would require an array of space telescopes the size of the U.S. But pictures of Earth do not reveal the presence of life unless they are taken at very high resolution.
Such images could be obtained with unmanned spacecraft sent to other solar systems, but the huge distance between Earth and any other planet makes this approach impractical.
Taking photographs, however, is not the best way to study distant planets. (…)
Searching for Another Earth
Planets similar to Earth in size and distance from their sun — ones likely to have oceans of water — represent the most plausible homes for carbon-based life in other solar systems. Water provides a solvent for life’s biochemical reactions and serves as a source of needed hydrogen. If each star has planets spanning a range of orbital distances, as occurs in our solar system, then one of those planets is likely to orbit at the right distance to sustain liquid water — even if the star shines more or less brightly than the sun.
Temperature, though, means little if a planet’s gravitational pull cannot hold on to oceans and an atmosphere. If distance from a star were the only factor to consider, Earth’s moon would have liquid water. But gravity depends on the size and density of the body. Because the moon is smaller and less dense than Earth, its gravitational pull is much weaker. Any water or layers of atmosphere that might develop on or around such a body would quickly be lost to space. (…)
The discovery of life on another planet, NASA administrator Daniel S. Goldin said, “would change everything — no human endeavor or thought would be unchanged by that discovery.”
ROGER ANGEL and NEVILLE J. WOOLF. This article updates a version that appeared in Scientific American in April 1996. SA
Copyright 1998 Scientific American, Inc.[Adapted]
Escrito por Nunes às 23h14
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Todas as questões são baseadas no texto acima:
01. It is correct to say that
a) this is an e-mail to talk about life in other solar systems.
b) this is an article to update a version published in a scientific magazine
c) this is a letter from ROGER ANGEL to NEVILLE J. WOOLF.
d) this is an article to tell students that extraterrestrial life is just a science fiction.
02. To the authors,
a) there are evident signs of life in other planets.
b) a simple modern telescope in space can detect signs of life in other planets.
c) big planets can not orbit distant stars similar to our sun.
d) maybe living organisms inhabit some smaller planets around stars.
03. Why taking photographs is not a good method to study distant planets? Because ______________
I) it would be necessary a very big array of space telescopes.
II) photos of the Earth planet [in normal resolution] do not reveal the presence of life.
III) the distance between Earth and other planets makes impractical the sending of spacecrafts to obtain photos.
Possible answer(s) to this question can be
a) only I
b) only II and III
c) I, II and III
d) only III
04. Planets similar to Earth in size and distance from their sun
a) can not have water for life’s biochemical reactions
b) do not need hydrogen to maintain life.
c) are the most evident home for carbon-based life – if they have oceans of water.
d) shines more or less brightly than the sun.
Escrito por Nunes às 23h14
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05. Em “If each star has planets spanning a range of orbital distances, as occurs in our solar system, then one of those planets is likely to orbit at the right distance to sustain liquid water” os autores apresentam o argumento de que
a) se cada estrela tem planetas em órbitas de diferentes distâncias, como ocorre no nosso sistema solar, é possível que algum deles tenha sua órbita a uma distância que lhe permita sustentar a água líquida em sua superfície.
b) todos os planetas têm órbitas diferentes em seus sistemas solares, por isso não podem sustentar a água líquida em suas superfícies.
c) todas as estrelas têm planetas em órbitas semelhantes ao nosso sistema solar, conseqüentemente, em todos pode haver água.
d) se cada estrela tem planeta em órbitas de diferentes distâncias, como ocorre no nosso sistema solar, então somente a terra poderá sustentar água líquida em sua superfície.
06. But the distance from the planet to its star is not the only factor to assure water in its surface. The other factor is
a) brightness of its star
b) how many moons the planet has
c) the distance from the Earth.
d) the planet’s gravitational pull
07. Em “If distance from a star were the only factor to consider, Earth’s moon would have liquid water.” as autores justificam que
a) se a distância do planeta à sua estrela fosse o único fator para esse reter oceanos e atmosfera, haveria água líquida na lua da terra.
b) a distância do planeta à sua estrela faz com que seja possível haver água líquida na lua da terra.
c) a lua é muito mais distante da terra do que a terra é do sol, e por isso não pode haver água líquida lá.
d) se a distância entre as estrelas fosse o único fator a considerar, a lua da terra teria água líquida.
08. Devido a força gravitacional da lua ser como se apresenta,
a) qualquer água ou camada de atmosfera que pudesse se desenvolver lá seria rapidamente perdida no espaço.
b) qualquer água ou camada de atmosfera que pudesse se desenvolver lá daria início ao ciclo da vida.
c) qualquer água que pudesse se desenvolver lá geraria uma nova camada de atmosfera.
d) qualquer água ou camada de atmosfera que se desenvolvesse lá se perderia no solo lunar.
Escrito por Nunes às 22h56
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