Space exploration is the exploration and discovery of outer space by use of space technology and is conducted by both robotic spacecraft and humans. Astronomy, which is the viewing of objects in space from Earth, is thought to predate recorded history, but it was the inspiration to modern space exploration. Humans explore space for many reasons including the survival of humankind if Earth cannot sustain life, uniting nations, and scientific research.
Physical space exploration began in Germany, where scientists developed and tested a V-2 rocket during World War II. This rocket became the first man-made object to enter space, alongside the launch of the A-4 in October of 1942. After the war ended, the United States used rockets captured from the Germans and their scientists to research and study rockets for military and civilian purposes. Although the Germans launched the first man-made object into space, the first exploration of space occurred in May of 1946, when the United States launched a V-2 for an experiment to analyze cosmic radiation.
In 1947, fruit flies became the first animals in space and the first pictures of Earth were taken. Both of these experiments were conducted using American V-2s. The Soviets also launched animal and radiation experiments in 1947, with the help of German scientists. These experiments were conducted using a variant of the V-2 known as the R-1. All of these early space exploration experiments were limited to short flights in sub-orbital space.
The Soviets conducted the first successful orbital mission in October of 1957 after launching the unmanned space vehicle Sputnik 1. This satellite weighed around 184 pounds and transmitted beeps down to radios across the earth, which scientists analyzed to measure the electron density in the ionosphere. The beeps also contained encoded information about the temperature and pressure of Sputnik, which helped researchers know its safety status. Sputnik eventually burned up upon re-entering the atmosphere, but its launch and success paved the way for other missions, including the successful launch of Explorer 1 by America in 1958. The first human flight was launched by Russia in 1961, successfully sending cosmonaut Yuri Gagarin into space for one Earth orbit aboard Vostok 1. America launched Mercury-Redstone 3 about a month later with Alan Shepard on board, but this flight was suborbital.
The next step in space exploration was successfully landing an object on a planetary body. This was accomplished in 1959 when Russia’s Luna 2 landed on the moon. America’s Apollo 11 was the first manned spacecraft to reach the moon. Venera 7 was the first spacecraft to land on another planet, landing in 1970, but this mission lasted less than thirty minutes. Important figures in space exploration include Kerim Kerimov, who was one of the leaders in the Vostok 1 mission, and Christopher C. Kraft, Jr., who was NASA’s first flight director.
Through the 1970s NASA ramped up its space exploration with the launches of several space orbiters, including one would much later make history. NASA launched Voyager 1 on September 5, 1977, an orbiter that was expected to last several years, exploring the outer planets. It visited Jupiter in 1979 and Saturn in 1980. The spacecraft’s primary mission ended on November 20, 1980, however, Voyager 1 is still going strong today, 36 years later.
Space Exploration got a huge lift when NASA launched the first Space Shuttle mission on April 12, 1981. That launch touched off a 30-year manned space program that saw 135 crewed missions into space. In 2000, the International Space Station paved a way for a continuing human presence in space. The Space Shuttle then became utilized as a vehicle to transport humans to and from the orbiting lab. After 11 years of supplying humans and cargo to the ISS, the Shuttle program was retired, leaving Russia as the only space agency capable of launching humans to and from the ISS — aboard its Soyuz spacecraft.
During the 2000s, many plans were announced for space exploration, including China’s plan to build and launch a 60-ton multi-module space station by 2020. NASA announced in the NASA Authorization Act of 2010 that it would build the Space Launch System (SLS), which would carry important equipment for experiments, the Orion Multi-Purpose Crew Vehicle, and other needed cargo. This station would also provide international and commercial transportation services to the International Space Station.
The focus of space exploration has shifted to using automated vehicles because these make missions less expensive to operate and allows researchers to gather information from areas where humans cannot reach. Optimal automated vehicles should be able to operate if something fails, should be able to attain a goal with a given set of actions, and should be able to sense its environment and make choices based on its findings. These types of vehicles would provide space programs throughout the world the ability to explore deep space with great efficiency.
After the retiring of the Space Shuttle program in 2011, NASA began looking for large corporations to fund the future of space travel. Several companies had already been working on space vehicles and were looking to secure contracts with NASA and other agencies to launch vehicles into space.
SpaceX was the first company to move in this direction when it successfully launched its Dragon capsule in 2012 and successfully docked with the ISS. Orbital Sciences has also shown commercial success after launching its Cygnus resupply ship to the orbiting lab in 2013.
Among the most historic feats accomplished in the space exploration field is the deep space exploration that has occurred with NASA’s Voyager 1, which has traveled more than 11 billion miles since its launch in 1977. NASA reported in September 2013 that the orbiter has made history when it left the heliopause, moving out of the Solar System and into interstellar space.
Image Caption: Artistic illustration of Cassini orbiter in Saturnian system. Credit: NASA/Jet Propulsion Laboratory