7. Translate the following word combinations and parts of the sentences into Russian:

since ancient times; to revolve around the Earth; not to agree with the model; the results of his many years of work; on one’s deathbed; to observe; an eclipse of the Sun; to record carefully; the exact positions of the planets and stars; to orbit the Earth; to be worth of observations; to explain the number, distance, and motion of the planets; to exert a force on the planets; careful analysis; the motion of every planet and satellite; the paths of the planets; long-period comets; short-period comets; orbital period; to sweep out equal areas in equal time intervals; a mathematical relationship; mean distance; the square of the ratio of the periods; average distance; artificial satellites.

8. Translate the definitions into Russian. Find in the text terms defined by these definitions:

1. the scientific study of the Sun, the earth, the Moon, stars, planets, etc.;

2. a natural object that moves around a larger natural object in space;

3. the amount of space between two thing or places;

4. a complete circular movement around the point, especially of one planet around another;

5. a simple description of a system, used for explaining how smth. works or calculating what might happen, etc.;

6. to go in a circle around the central point;

7. a mass of dust and ice that moves around the Sun and looks like a bright star with a tail;

8. an occasion when the Moon passes between the Earth and the Sun so that you cannot see all or a part of the Sun for a time;

9. a large round object in space that moves around a star (such as the Sun) and receives light from it;

10. a large ball of burning gas in space that we see as a point of light in the sky at night;

11. a curved path followed by a planet or an object as it moves around another planet, star, etc.

9. Answer the following questions:

1. What did ancient people assume concerning the Sun, the Moon, planets and stars?

2. Was Nicholas Copernicus a Polish astronomer or a Czech mathematician?

3. When were the results of his many years of work published?

4. Nicholas Copernicus assumed that the Earth and other planets revolve around the Sun, didn’t he?

5. Tycho Brahe observed an eclipse of the Sun on August 21, 1560, didn’t he?

6. How long did T. Brahe study astronomy as he traveled throughout Europe?

7. What did T. Brahe conclude after having carefully recorded the exact positions of the planets and stars?

8. Who inherited 30 years’ worth of T. Brahe’s observations?

9. J. Kepler believed that the Earth exerted a force on the planets and placed the Earth at the center of the system, didn’t he?

10. What does Kepler’s first law state?

11. According to Kepler’s ideas Comets are divided into two groups (long-period comets and short-period comets), aren’t they?

12. What are the examples of comets of short-period comets and long-period comets?

13. What does Kepler’s second law state?

14. What does Kepler’s third law state?

15. Do Kepler’s first two laws apply to each planet, moon, and satellite individually?