History of exploration III (modern era)

Until the dawn of the twentieth century, exploration of Earth's surface was limited to the surface itself. The summits of the highest mountains, the depths of the oceans , and sky and space were unexplored. Technological advances, as well as fundamental shifts in scientific theory, opened the entire world, and beyond, to exploration. The twentieth century was the golden age of discovery, rivaled only by the Copernican Revolution and the European discovery of the New World in the fifteenth century.

In 1859, Charles Darwin published a natural history work that sparked great controversy. Darwin's book, On the Origin of Species, was a compilation of his scientific observations from an expedition to the Galapagos Islands. Darwin's observations led him to construct a model of the evolution of various animal species, including man. Over the course of his career, Darwin built upon Charles Lyell's earlier works on the antiquity of Earth. Darwin proposed that the dawn of man was not because of spontaneous creation, but was the result of a process of evolution and natural selection, the principle of survival of the fittest, which occurred over hundreds of thousands of years. Darwin thus concluded that man, animals, plants, geology , and environment were all connected in their development. During the course of the nineteenth century, some aspects of Darwin's theory fell out of favor, such as the principles of natural selection and inheritance, after the discovery of genetics. However, Darwin's work popularized the idea of evolution, brought it into mainstream science, and opened up the fields of anthropology (the study of man) paleontology (the study of fossils ) and geology (the study of Earth.)

At the turn of the twentieth century, wider communication was possible through the telegraph and telephone.

Railroads, steamships, and later automobiles allowed people to travel with greater ease. A voyage that took Columbus four months in 1492, took passengers a scant four days in 1915. The Panama Canal connected the Atlantic and Pacific Oceans, eliminating the need to traverse the feared and time-consuming Straits of Magellan. The advent of flight in 1901 provided the final link; within 60 years, even transatlantic passenger ships were rendered artifacts of the past. Flight also allowed man to see the surface of the earth from above, changing the way cartographers created maps. Electricity and cameras further revolutionized the perspectives from which people viewed the earth. This connectivity with once distant and remote places made the world seem smaller, while photography made the remote corners of the world accessible to everyone.

Exploration of the earth's surface continued. In the early decades of the twentieth century, several men led expeditions to the South Pole. In 1909, British explorer, Ernst Shackleton's voyage to Antarctica was particularly ill-fated, leaving much of the crew stranded on the continent as ice floes crushed the ship. The team did not reach magnetic south, but provided some of the first observational clues that Antarctica was a landmass, not only a polar ice cap like its northern counterpart. Norwegian explorer Roald Amundsen reached magnetic south in 1911, and attempted to reach the North Pole in 1926, but failed. Not until 1978 did a manned expedition reach the surface of the North Pole. In 1953, British mountaineer Sir Edmund Hillary and his guide Tenzing Norgay climbed Mt. Everest on the border between Nepal and China. The mountain is the highest peak on the earth's surface (the only larger mountains are submerged beneath the sea). Everest continues to be a draw to adventurers and explorers, claiming several lives on its harsh slopes.

By the middle of the twentieth century, most of Earth's surface had been explored. As technology grew more sophisticated and complex, explorers turned to space, the inner layers of the earth, and the unknown depths of the sea as venues for modern exploration and discovery. After World War II, the technology that was developed for the war was not only used for weapons, but also for scientific research. Remote sensing equipment such as sonar was used for mapping the ocean floor and locating ridges, reefs, and other underwater features. Jet engines, rockets, and robotics allowed for the launching of satellites by the United States and the Soviet Union in the late 1950s. The "Space Race" followed, with the Soviet Union and the United States each competing to achieve landmark space explorations before the other nation. In 1961, The USSR sent the first man, Yuri Gagarin, into space. The United States soon followed, sending the first astronaut to orbit Earth. Then, the ultimate goal of each nation was to send a team of astronauts to the Moon . In 1969, the United States sent the first team of astronauts, aboard the Apollo 11 craft, to the surface of the moon. Aside from meteoroids that crashed into the earth, the Moon mission was man's first contact with an alien geology.

In the 1990s, the United States and several other nations, including Russia, renewed their interest in space research. The International Space Station was planned and constructed, providing the first non-earthbound research laboratory. A growing fascination with deep-space exploration and astronomy prompted the launch of the Hubble Space Telescope to photograph stellar bodies that could not be clearly investigated on the earth's surface. In 2001, missions of unmanned probes to Mars yielded information about Martian geology, giving scientists their first basis of comparison for Earth's geological processes.

Just as exploration in centuries past was largely driven not only by curiosity but also by the need for certain goods and resources, exploration in the twentieth century was similarly motivated. The Industrial Revolution created the need for vast amounts of fuels—at first coal , then natural gases, and then nuclear materials. The first coal mines were dug in Britain in the 1200s, and the process of mining changed little from then until the 1800s, when railroads, steam engines, and steel were introduced to expedite production, processing, and increased mine safety. Research about the deep geology of the earth's crust not only altered mining processes but also opened new venues to resource acquisition, such as the ocean floor, and led to the discovery of new fuels , such as petroleum and uranium. Deep-crust geology gave scientists a better understanding of how forces within the earth combine with organic materials to produce these fuels.

Today, only the uppermost layers of the planet have been explored. The technology does not currently exist to drill or explore to the molten sub-crust surfaces. While studying earthquakes and volcanoes has helped researchers understand geological processes, sub-surface exploration remains limited.

With less than ten percent of the ocean floor mapped, explored, or even seen by human eyes, the depths of the oceans are perhaps the last great arena for man's exploration of his planet. Submarines and submersibles first appeared in the 1780s, but not until the invention of the German U-boat (battle submarine) in World War I was there technology for breathing apparatuses, long-term, deep submersion, and propulsion. The first viable and practical self-contained breathing apparatus (or SCUBA) was introduced in the early 1900s. In 1930, William Beebe created a bathysphere, a personal submersible that was lowered from a ship and dragged at a given depth. Beebe dove to 1,427 ft (435 m), deeper than modern personal SCUBA equipment can attain. Beebe thus pioneered the small submersible, which later became the fixture of deep-sea exploration.

By World War II, submarines were standard naval warfare ships, and diving gear such as the Mark V diving helmet, were standard. After the war, their principals of design were applied to scientific research. In the 1970s, scientists and engineers designed a small submersible named ALVIN. The submersible had a mechanical arm, modern surveying and recording equipment, and room for up to three researchers. The submersible was motorized, and once lowered, its crew could drive it for a more free range of exploration. This generation of submersibles could be used miles beneath the surface, and entered realms of the ocean that no human had ever seen. Some of the first notable discoveries were that of deep-water marine life. Without light or heat, scientists thought that no life could survive on the sea floor. Instead, researchers discovered a vibrant community of strange and primitive-looking creatures that thrived at great depths.

In 1973 and 1974, the Mid-Atlantic Ridge, a large underwater mountain range, was explored by divers in small submersibles that were equipped with sensory and photography devices. That same decade, scientists discovered underwater volcanic vents, thus gaining insight into the creation of the ocean floor itself. The discovery of hydrothermal vents provided a new means of understanding ocean chemistry , and the circulation of minerals , necessary for sustaining marine life, at great depths. Deep-sea exploration was further utilized in archaeological endeavors to locate sunken shipwrecks and other submerged sites. In 1985, Dr. Robert Ballard, who was part of many of the great deep-ocean expeditions of the late twentieth century, discovered the wreck of the RMS Titanic, a British luxury liner—the technological marvel of its time—that sank in 1912.

Not all modern exploration is achieved on a grand scale. During the modern era, explorers and scientists have also embarked on projects to explore mankind, both in the past and present. Physical anthropologists unearthed early hominid (human or human-like) fossils in the African Rift Valley as early as the nineteenth century. However, not until the last half of the twentieth century did scientists attempt to establish a chronology of man to match the desert fossils. In 1974, anthropologists Donald Johanson and Tom Gray discovered a nearly complete hominid skeleton. The bones, named Lucy, formed the then most complete skeleton of one of the earliest known human ancestors, Australopithecus. The skeleton dates back 3.18 million years—far longer than Darwin predicted over a century before.

Today, ethnographers (people who record other cultures) and other anthropologists study groups of people around the globe, especially those who live in the most remote areas and have little contact with other peoples. Archaeologists work to unearth the material remains of the past as a means of scientifically exploring the course of human history. Thus, the exploration of man is as concerned with re-discovery as it is with novel discovery.

Marine biologists are searching for the most primitive forms of life, often small, wormlike creatures and sponges, in the depths of the ocean. Mathematician and physicist, Albert Einstein , paved the way for exploration of atoms, and other fundamental structures of the universe. Physicists continue to break down these elemental structures into sub-atomic particles. Other physicists and astronomers research particles, gases, and forces in space to determine provide clues about the few hundredths of a second in the life of the universe.

See also Bathymetric mapping; Dating methods; Deep sea exploration; Evolution, evidence of; Geographic and magnetic poles; Historical geology; History of exploration I (Ancient and classical); History of exploration II (Age of exploration); History of manned space exploration; Hubble Space Telescope (HST); Petroleum, history of exploration; Physical geography