a. The idea is undermined by new discoveries: 1) supported; 2) underdeveloped; 3) proved beyond doubt; d) made less valid.
b. The position of our planet is eerily fortuitous: 1) surprisingly fortunate; b) probably rather unfortunate; c) due to a mysterious coincidence; d) determined by multiple factors.
c. This figure is too infinitesimal to record: 1) small; 2) unbelievable; c) infinite; d) improbable.
d. The Drake equation is flawed: a) has errors; 2) is a brilliant guess; c) is generally supported; d) has many important consequences.
3. Sum up M. Schmidt’s intention in just a few sentences (without using ready-made sentences from the text). (The article focuses on … The author provides data which points to … The author reasons that … Mr. Schmidt militates in favour of … His arguments unequivocally suggest that ….)
4. In class we will watch Carl Sagan give his interpretation of the Drake equation. Take note of his explanations. In pairs do your own calculations using whatever data you think is appropriate. Report your ideas to the class.
The Drake Equation was developed by Frank Drake in 1961 as a way to focus on the factors which determine how many intelligent, communicating civilizations there are in our galaxy. The Drake Equation is:
N = N* fp ne fl fi fc fL
The equation can really be looked at as a number of questions:
N* represents the number of stars in the Milky Way Galaxy
Question: How many stars are in the Milky Way Galaxy?
Answer: Current estimates are 100 billion.
fp is the fraction of stars that have planets around them
Question: What percentage of stars have planetary systems?
Answer: Current estimates range from 20% to 50%.
ne is the number of planets per star that are capable of sustaining life
Question: For each star that does have a planetary system, how many planets are capable of sustaining life?
Answer: Current estimates range from 1 to 5.
fl is the fraction of planets in ne where life evolves
Question: On what percentage of the planets that are capable of sustaining life does life actually evolve?
Answer: Current estimates range from 100% (where life can evolve it will) down to close to 0%.
fi is the fraction of fl where intelligent life evolves
Question: On the planets where life does evolve, what percentage evolves intelligent life?
Answer: Estimates range from 100% (intelligence is such a survival advantage that it will certainly evolve) down to near 0%.
fc is the fraction of fi that communicate
Question: What percentage of intelligent races have the means and the desire to communicate?
Answer: 10% to 20%
fL is fraction of the planet's life during which the communicating civilizations live
Question: For each civilization that does communicate, for what fraction of the planet's life does the civilization survive?
Answer: This is the toughest of the questions. If we take Earth as an example, the expected lifetime of our Sun and the Earth is roughly 10 billion years. So far we've been communicating with radio waves for less than 100 years. How long will our civilization survive? Will we destroy ourselves in a few years like some predict or will we overcome our problems and survive for millennia? If we were destroyed tomorrow the answer to this question would be 1/100,000,000th. If we survive for 10,000 years the answer will be 1/1,000,000th.
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When all of these variables are multiplied together when come up with:
N, the number of communicating civilizations in the galaxy.
The real value of the Drake Equation is not in the answer itself, but the questions that are prompted when attempting to come up with an answer. Obviously there is a tremendous amount of guess work involved when filling in the variables. As we learn more from astronomy, biology, and other sciences, we'll be able to better estimate the answers to the above questions.
5. Do you adhere to the viewpoint supported by Michael Schmidt or do you share Carl Sagan’s vision of the universe and the Earth’s place in it? Select and present the arguments that sound most convincing to you.
6. View the opening fragment of the video “Cosmos” (Episode 1) by Carl Sagan (in class). Pick up the English for the following:
Космос непостижимо насыщен материей. Мы все – из Космоса и жаждем туда вернуться. Мы отправимся в научную экспедицию на корабле Воображения, где нас не будут сковывать (to fetter) размеры Вселенной, а скорость полёта – не ограничена.
Теперь мы в просторах Вселенной, еще не нанесенных на небесные карты (to chart). Обычные меры расстояния не применимы к галактическим просторам. Нужна б о льшая единица - световой год, то есть расстояние, которое свет проходит за год.
Отдельные галактики рождаются, старятся, умирают, могут взрываться и сталкиваться. Составляющие их звезды также могут взрываться …
Каждое звёздное скопление (cluster) вращается вокруг массивного галактического ядря, словно рой пчёл, объединенных силой притяжения. Млечный путь – тоже галактика. Её спиральные рукава делают оборот каждые …. (how many?) … лет
HOME ASSIGNMENT
Compose a 1000 word essay on the theme “ Are we alone in the Universe”. Use some of the ideas from this lesson and materials to generate your own ideas and conclusions. To be handed in 1 week after this lesson. Don’t forget to quote your sources.