Man and the Universe
(From the history of
astronomy)
It is thought that man studied
the stars, the planets, the Moon and the Sun in prehistoric times and it is
believed that ancient monuments such as the Pyramids were built upon
astronomical knowledge.
What prehistoric ideas of
heavenly bodies may have been we do not know, except where some written
evidence has come down to us to decipher.
Probably the first big step
was the idea that the earth was a sphere. That idea, although, it was wrong, made
it possible to assert that the heavens revolved around the earth.
The Greeks made great advances
in geometry and mathematics from the observations they could make with the
naked eye and simple instruments for measurement. They measured rather accurately
the diameter of the earth and the distance to the Moon, but they could not
measure greater distances such as the distance to the Sun. They developed the
geocentric theory of the Universe according to which the Earth was a stationary
body around which everything revolved. This was the Ptolemaic system.
Even in the Middle Ages
astronomers thought the system was correct, and, though there were philosophers
who considered it wrong, they could give no proof tosupport
their ideas.
It was Copernicus who developed
a new theory of a heliocentric solar system. That was a much simpler idea and
explained many of' the errors discovered by increasing accuracy of
measurements, especially of the movement of the other planets.
Kepler perfected the
Copernican theory and Newton's law of gravitation, explained it so clearly that
even reactionary scientists had to accept it. With the help of the new
astronomic instrument, the telescope, it became clear that the geocentric
theory was entirely wrong. Even so, it was only in 1837 when Bessel measured
the actual distance to the nearest star (or so he thought) that scientists
received the final proof that the heliocentric theorywas correct.
This required powerful
telescopes and very accurate measurements down to a small fraction of a second
of arc (1/3600 part of a degree of an angle). Bigger telescopes with
photography helped man to look deeper intospace. Scientists could
now see beyond our solar system, beyond ourGalaxy. They
foundthere were other galaxies, so far away that the light from them
travelled many million years before itreached our planet. With the help of the
spectroscope itbecame possible to see those tiny beams of light, to learn
the composition of stars, their temperature andeven the speed at which they
were travelling away
from us or towards us.
Einstein's theory of
relativity added information to Newton's gravitation law.
The new knowledge of
sub-atomic physics and thermo-nuclear reactions gave us theoretical ideas about
the life history of stars, and the conditions and reactions that may be found
on them.
Then came radio astronomy
which helped to explore invisible objects beyond the reach of any telescope.
And now we are living in the Cosmic
era. Rockets have been sent to the Moon, round the Moon, giving us views man
has never seen before.
Vocabulary
1. somewrittenevidencehascomedowntoustodecipher– некоторые еще не
расшифрованные письменные свидетельства дошли до нас
2.made it possible to assert – давала возможность утверждать
3. with the naked eye – невооруженным глазом
4. Ptolemaic system – геоцентрическая
система Птолемея
5. It was Copernicus who
developed a new theory of a heliocentric solar system–лишьКоперниксумелобосноватьсвоюновуюгелиоцентрическуюсистему
6. that scientists received
the final proof that the heliocentric theory was correct–ученыеполучилиокончательноедоказательствоправильностигелиоцентрическойтеории
7. down to a small fraction
of a second of arc–сточностьюдомалыхдолейсекундыдуги
8. heavenly – небесный
9. evidence – свидетельство
10. probably – возможно
11. advance – открытие
12. according to smth. – согласно
чему-либо
13. stationary – неподвижный
14. the Middle Ages – Средние века
15. consider – считать, учитывать
16. proof
– доказательство, свидетельство
17. law
– закон
18. scientist – ученый
19. entirely – полностью, всецело
20. tiny beams of light – крошечные пучки света
21. Einstein’s theory of
relativity – теория относительности Эйнштейна
22. invisible objects – невидимые объекты
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