Explain what the author means by the following statements.

1. A laser is a source of light but unlike anything that had ever been

seen before 1960.

2. With this invention the laser age was born.

3. According to this legend, they are supposed to work fairly well.

4. In many ways, the laser was a solution looking for a problem.

5. In fact, it is safe to say that the vast majority of laser applications

have not yet even been suggested.

6. If treated inadequately, an extremely powerful beam of laser light

can be a source of destruction.

Write two paragraphs, one about advantages, the other about possible

Dangers of lasers.

 

 

LESSON 12

Scientific Exploration

Discuss the following questions.

a) How do scientists explore micro- and macroworlds?

b) What means of scientific exploration do you know?

c) Do you believe we can contact alien civilizations? How?

 

2.Read and learn the new words, write them down into your vocabulary:

Alien -іноземець

Scanning- перегляд

Interstellar- міжзоряний

Hardly -навряд

Detected- визначений

Maintained- підтриманий

Advanced- прогресивний

Fruitful - плідний

Across- через

Lasting- тривалий

Brief- короткий

Entire-п овний

Spot- пляма

Brighter - яскравіше

Distant -віддалений

Practicabl e-реальний

Read the students' conversation and learn about an unusual

Application of the laser telescope.

Peter: Pavel, have you heard about artificial stars?

Pavel: Not yet, but I'd like to know about them more, anyway.

Peter: Well, this article says they are created with the help of a laser telescope. One of these experiments is described here.

Pavel: Really? And what was the result of the experiment?

Peter: The reporter claimed that a bright sodium star, as big as about a natural star, had been generated.

Pavel: That sounds fascinating! How was the experiment carried out?

Peter: Oh, it was said in the article that the Solar Vacuum Tower Telescope had launched a 4-watt laser beam to the atmosphere and recorded the return light from the generated artificial star at the same time.

Pavel: Why do you think this artificial star has been created?

Peter: Well, there may be other reasons but I'm sure the star will serve as a model for further research of the universe.

Pavel: Oh really? May be in this way we'll be able to establish interstellar communication?

Peter: That's a good idea, but the scientists will have to carry out a number of experiments to prove that.

 

Complete the dialogue.

- How are artificial stars...?

- As far as I know, a laser telescope is....

- And... about any successful...?

- Yes, yesterday I found out...

-... interesting.... carried out?

- …

- I wonder why...

-Well...

- Do you suppose...?

- …

Match a line in A with a line in B.

А В

1. Would you like to know more a) An unusual application of

about artificial stars? a laser telescope.

2. What are the means of b) They believed radio waves were

scientific exploration? the most energy-efficient way of

3.What does the article deal sending signals across the space.

with? c) A telescope and a microscope,

4.What did the reporter claim? for example.

5.The scientists hope they'll d) Of course, I would!

contact distant civilizations e) He maintained that an artificial

with the help of a laser. sodium star had been generated.

6.Why did scientists look for f) That sounds fascinating!

radio signals from aliens?

 

Read the article attentively and learn how scientists try to establish

Interstellar communication.

BBC News Online

 

A telescope designed to search for laser signals from alien intelligences is to start scanning the skies next year. The 1.8-metre (6 ft) Optical SETI (Search for Extra-Terrestrial Intelligence) Telescope is currently being built in Harvard.

For more than 40 years, scientists have looked for radio signals from aliens on the understanding that radio waves provide the most energy-efficient way to send a signal across interstellar distances. But despite using the world's largest radio telescopes with highly sensitive detectors, no sign of a signal has been found in space as yet.

Several years ago some astronomers said it was hardly surprising that no radio signal had been

detected yet. They maintained that researchers might be looking for the wrong kind of message. It was assumed that a technologically advanced race might be more likely to communicate using pulsed laser beams rather than radio. The new approach was hoped to be more fruitful.

Searching for laser pulse signals was first suggested by the Nobel

prize winning scientist Charles

Townes in 1961 and was, according to

its supporters, met with 'more

interest than enthusiasm'. It was

thought that a high-powered laser

coupled with a large telescope could

send a signal across many light

years of space. Scientists believed

that an alien laser beam would be

pulsed to encode a signal.

During the pulse, lasting perhaps

less than a millionth of a second, the

laser light could be much brighter

than the light from the star in the

system from which the signal is being

 

sent. The new SETI Telescope will look for these brief pulses of laser light, scanning the entire northern sky once every 200 clear nights. It will have a special camera fitted with an array of 1,024 ultra-fast detectors that can spot flashes as short as a billionth of a second.

According to the researchers, using only the Earth 2001 technology we can now generate a beamed laser pulse that appears 5,000 times brighter than our Sun, as seen by a distant civilization. In other words, interstellar laser communication is altogether practicable with the new Optical SETI Telescope searching the sky for such signs of intelligent life elsewhere in the galaxy.