Text A. WHAT IS A STAR?

A star is a body of luminous gas, like the sun. But as stars are much farther away from the earth than the sun, they appear to be only small points of twinkling light. With the naked eye it is possible to see about 2,000 stars at any one time or place but with the most powerful telescope over 1,000 million stars are visible. Although light travels at 186,000 miles a second, the light from the stars takes many years to reach the earth.

Stars are not fixed in space, but are traveling in different directions at different speeds. Seen from the earth, these movements appear to be so small that groups of stars, or constellations, seem to have a permanent relationship. The star patterns we see in the sky are almost the same as those seen by our ancestors hundreds, or even thousands of years ago.

The sizes of stars vary tremendously, from less than the diameter of the sun to thousands of times its size. Most stars appear white when looked at with the naked eye, but some are bluish-white, yellow, orange and red. The varied colours are due to differences in surface temperature. The brilliant, white stars are hottest with surface temperatures of several hundred thousand degrees. The less brilliant, orange and red stars have surface temperatures of about 2, 000 degrees.

There are exceptions, however. The red giant, Betelgeux, in the constellation (or group) of Orion, appears to be brilliant because of its size. Its diameter is 250 million miles, which is greater than the diameter of the earth's orbit round the sun.

Shooting stars which are sometimes seen moving across the night sky for a few seconds are really meteors. These small particles flare up as they strike the earth's atmosphere and usually burn out.

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I. Practise the pronunciation of the following words:

luminous, earth, surface, orange, giant, diameter, meteor, farther, naked, ancestor, tremendously.

II. Match the adjectives and nouns:

III. Read and translate the words of the same root. Pay attention to suffixes:

A. to differ - difference - different;

to relate - relation - relationship;

to vary - variety - various;

to move - movement - movable;

to direct - direction - directly;

to except - exception - exceptional.

B. real - really;

usual - usually;

tremendous - tremendously;

visible-visibly;

careful - carefully.

IV. Read and translate the words with the component tele - Mind! The Greek word "tele" means "far, at a great distance":

telegraph, television, telescope, telephone, telefax, telepathy, telemetry.

V. Memorize the following word combinations:

VI. Read the text ‘What is a star?’. Answer the questions below:

1. What is a star? Find the definition in the text.

2. How many stars can a man see with the naked eye? With the most powerful telescope?

3. How long does it take the light from the stars to reach the earth?

4. Stars are not fixed in space, are they?

5. What do we call groups of stars?

6. How do the sizes of stars vary?

7. What are the varied colours of stars due to?

8. Which stars are the hottest?

9. What surface temperatures do the hottest stars have?

10. What are meteors?

VII. Complete the sentences.

1. A star is....

2, It is possible tо see....

3. The light from the stars takes....

4. Stars are traveling....

5. Constellations seem to have....

6. The sizes of stars....

7. The varied colours of stars....

8. Shooting stars are....

VIII. Find in the text ‘What is a Star?’ the sentences with the Subjective Infinitive Construction. Translate them.

IX. Say what you have learned from the text about:

a) the number of visible stars;

b) the speed of light;

c) the sizes of stars;

d) the colours of stars;

e) shooting stars.

X. Imagine you are a teacher of astronomy. Deliver a lecture on the topic ‘What is a Star?’.

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