Introduction to Planetary Science

the urge to explore 3
deliberating for four years, the Commission
declared that Columbus’ proposal was nonsense.
However, the defeat of the Moors by the Spanish
armies in the battle of Granada in 1492 caused the
Queen to reconsider. Columbus was recalled to
the Spanish court and his proposal was approved
on April 17 of 1492. Six months later, on October
12, Columbus sighted land after sailing west
across the Atlantic Ocean six years before Vasco
da Gama reached India.
Christopher Columbus had, in effect, rediscovered
North America which had been
populated thousands of years earlier by people
from Siberia and which had also been visited
by Vikings led by Leif Eriksson, son of Erik
the Red, who had established a settlement in
Greenland in 986 AD. In fact, all of the continents
(except Antarctica) and most of the large
islands contained human populations in the 15th
century when the Portuguese began their quest
to find a way to India, China, and the islands in
the Molucca Sea of Indonesia.
In spite of the discoveries Christopher
Columbus had made, he had not actually reached
China or the Moluccas. Therefore, Emperor
Charles V of Spain authorized the Portuguese
nobleman Ferdinand Magellan to reach the
Moluccas by sailing around the southern end
of the landmass that Columbus had discovered.
A small fleet of five ships sailed on September
20, 1519, with 200 people on board. One year
later, on November 28, 1520, the three remaining
ships sailed through a narrow passage (now
known as the Straits of Magellan) and entered
a new ocean on a calm and sunny day. Accordingly,
Magellan and his surviving associates
named it the Pacific Ocean. However, the
voyage across the Pacific Ocean was a nightmare
because of the lack of fresh food and water. Many
crew members died of scurvy and Magellan
himself was killed in a battle with natives in the
Philippines. The 18 survivors completed the first
circumnavigation of the Earth and returned to
Seville in 1522 AD after three years at sea.
All of the expeditions of the fifteenth to the
seventeenth centuries were motivated primarily
by the desire for wealth and power. The exploration
of the Earth that resulted from these
voyages was an unintended byproduct. Not until
the eighteenth century did scientific exploration
become a factor in motivating the expeditions
organized by England and France. Noteworthy
among the leaders of these extended voyages
of discovery were Captain Louis Antoine de
Bougainville of France (1729–1811) and Captain
James Cook of Britain (1728–1779).
Captain de Bougainville had an illustrious
career in the service of France. He first served as
aide-de-camp to General Louis-Joseph Montcalm
in Canada during the French and Indian War
(1756–1763) described by Anderson (2005). In
1763, he led an expedition to the South Atlantic
Ocean and set up a French colony on the
Falkland Islands. Next, he sailed around the
world between 1766 and 1769 accompanied by
a group of scientists. In 1772, de Bougainville
became the secretary to King Louis XV of France
and served as the Commodore of the French
fleet which supported the American Revolution
(1779–1782). After the French Revolution in
1792, he settled on his estate in Normandy. Later,
Napoleon I appointed him to be a Senator, made
him a Count, and a Member of the Legion of
Honor. He died on August 31, 1811, in Paris at
the age of 82.
James Cook learned his craft as a seaman on
wooden sailing ships that hauled cargo along
the North-Sea coast of England. In 1752 he
enlisted in the Royal Navy and participated in
the siege of Louisburg in Nova Scotia during the
Seven-Years War (1756–1763) between Great
Britain and France (Anderson, 2000). He also
helped General Wolfe to cross the St. Lawrence
River for an attack on the city of Quebec.
The British army commanded by General Wolfe
scaled the rocky cliff along the northern bank of
the river under cover of darkness and defeated
the French army of General Montcalm on the
Plain of Abraham on September 13, 1759.
In 1768 the Royal Society of England selected
James Cook to command the first scientific
expedition to the Pacific Ocean. His orders were
to transport a group of British scientists led by
Joseph Banks to the island of Tahiti in order
to observe the transit of Venus across the face
of the Sun on June 3, 1769. Subsequently, he
was ordered to sail south to explore the socalled
Terra Australis. During this leg of the
expedition Cook discovered and circumnavigated
New Zealand. He then crossed the Tasman Sea
and, on April 19,1770, discovered the east coast
of Australia. On this voyage he mapped not only