72 PART 1^ |^ EXPLORING THE SKY
■ Figure 4-21
The 99 years between the death of Copernicus in 1543 and the death of Galileo in 1642 marked the transition from the ancient astronomy
of Ptolemy and Aristotle to the revolutionary theory of Copernicus and, simultaneously, the invention of science as a way of understanding
nature.
1543 99 years of astronomy 1642
GALILEO
Milton
Bacon
Guy Fawkes
Rembrandt
Shakespeare
Napoleon
George III
Voltaire
J. S. Bach Mozart
William Penn
NEWTON
Edward Teach
(Blackbeard)
1666 London
Black Plague
American War
of Independence
Tycho’s nova
1572
Destruction of the
Spanish Armada
Voyage of
theMayflower
Magellan’s
voyage
around the
world
Sidereal Messenger
1610
Telescope
invented
20 yrs at Hveen
Law III
1619
Laws I & II
1609
Principia
1687
Kite
Dialogues
1632
Imprisoned
1633
French and
Indian War
TYCHO BRAHE
KEPLER
Tycho
hires
Kepler
1600
Elizabeth I
COPERNICUS
Luther
Michelangelo
Columbus
Leonardo
da Vinci
Beethoven
Benjamin Franklin
John Marshall
George Washington
1500 1550 1600 1650 1700 1750
What Are We? Participants
The scientifi c revolution began when
Copernicus made humanity part of the
universe. Before Copernicus, people
thought of Earth as a special place different
from any of the objects in the sky; but,
in trying to explain the motions in the sky,
Copernicus made Earth one of the planets.
Galileo and those who brought him to
trial understood the signifi cance of making
Earth a planet. It made Earth and
humanity part of the universe, part of
nature.
Kepler showed that the planets move
according to simple rules. We are not in a
special place ruled by mysterious planetary
forces. Earth, the sun, and all of humanity
are part of a universe whose motions can be
described by a few fundamental laws. If
simple laws describe the motions of the
planets, then the universe is not ruled by
mysterious infl uences as in astrology or the
whims of the gods atop Mount Olympus. And
if the universe can be described by simple
rules, then it is open to scientifi c study.
Before Copernicus, people felt they
were special because they thought they
were at the center of the universe.
Copernicus, Kepler, and Galileo showed
that we are not at the center but are
part of an elegant and complex universe.
Astronomy tells us that we are special
because we can study the universe
and eventually understand what we
are. But it also tells us that we are not
just observers of nature; we are
participants.
