Early Astronomers: their lives and discoveries.
For centuries many have marveled at the greatness of the Moon and even based traditions around it. Although one may think the Moon is so close and big enough to touch, only twelve people have actually touched the Moon and walked on its surface. In ancient times, Chinese, Babylonians, Greeks and Egyptians recorded their observations of the night sky. In the late 1500's - early 1600's however, came much change. Nicolaus Copernicus was the one who put the Sun in its proper place, the center of the Solar System despite Ptolemy's idea that the Earth was the center and the Sun and Moon went around it. Johannes Kepler wrote the laws of planetary motion: All planets follow an elliptical orbit around the Sun. The planets move faster when they are passing closer to the Sun. Each planet's orbit time is related mathematically to its distance from the Sun. Galileo Galilei however proved that Copernicus and Kepler were right. Through experiments and observations he was also able to disprove much of medieval science. Galileo is responsible for having built the first telescope. A device that was able to magnify objects to twenty times their size. Galileo discovered that the Moon wasn't smooth, because he was able to see the craters and mountains on the Moon's surface through his telescope. These discoveries proved that the planets and their Moons were actual worlds rather than the god like figures of light that many cultures dreamed them to be. Sir Isaac Newton is then credited for having discovered that gravity is simply the force of attraction among all matter. He noted that objects that are far apart have less gravitational attraction than objects that are close and that the more mass an object has, the greater its gravitational force. Additionally, Newton created a revolutionary reflecting telescope. From here, astronomers were able to use telescopes to get a closer look at what was out there, and used their observations to calculate the sizes of the planets, its' distance from the Sun, and rotation periods. Later new tools were introduced such as cameras to photograph telescopic viewing and the spectroscope that was used to magnify and split visible light into bands of color. It was not until 1956 however that the first liquid fueled rocket was launched which was followed closely by the first satellite, Sputnik 1 to orbit the Earth in 1957. One year later, in 1958, the National Aeronautics and Space Administration (NASA) was formed and the race for space began.
Reaching the Moon
The United States was the first to take a shot at reaching the Moon. Pioneer 0 a space probe (a robotic space explorer) packed with a camera launched in August of 1958 but exploded about a minute after lift off. Pioneer 1, NASA's first spacecraft was the launched toward the Moon with Pioneer 2 and Pioneer 3 closely following without success. Meanwhile the Soviet Union tried and failed at their first three attempts to reach the Moon via a lunar probe. The Soviet Union's Luna 1 became the first lunar flyby probe coming within four thousand miles of the Moon and artificial object to orbit the Sun where it remains today. Meanwhile, the United States Pioneer 4 became America's first flyby probe to the Moon but was unable to get close enough for pictures. The USSR's Luna 2 became the first spacecraft to touch the Moon, closely followed by Luna 3 which snapped pictures of the Moon. The 1960's brought in with it a new era of exploring the Moon. This time, scientists explored the idea of having humans become space travelers. The USSR and the United States did not begin with humans. NASA started with monkeys and chimpanzees while the USSR drafted canines. After successfully putting these spacecrafts in orbital flight around the Earth, the United States chose the 'Mercury Seven'. The Mercury Seven were the first seven astronauts "sailors of the stars" to be chosen by NASA to be sent into space. The actual first human in space however was a USSR cosmonaut, i.e. "sailor of the universe" by the name of Yuri Gagarin in 1961. Approximately 23 days later, Alan B. Shepard became the first American in space. With this, NASA developed the Apollo program which was created to send a man to the Moon. NASA then sent seven Surveyors to the Moon between 1966 and 1968 to map the Moons surface as earlier seen through lunar pictures sent by Ranger 7. Finally NASA sent five lunar orbiters to the Moon to scout a landing site. By the time the Ranger, surveyor and Lunar Orbiter missions were complete, Apollo astronauts were not left with any guesswork about what they would find on the Moon and where they would land. The orbiters also checked the radiation levels and looked for meteoroids in order to design spacesuits to protect the astronauts. Despite all of this work, the first Apollo mission unfortunately ended before it left Earth when the capsule caught fire in 1967. After having been put on hold for some time, Apollo 4, Apollo 5, Apollo 6 were launched without a crew as test runs. Apollo 7 and Apollo 8 carried astronauts into space to orbit the Earth, demonstrate the command and service module and test communication systems. Apollo 9 and Apollo 10 followed carrying with it a crew to test the performance of the landing sites by passing over them, evaluate the performance in lunar orbit and the lunar environment. These rehearsals made way for Apollo 11 which launched on July 16, 1969 from Kennedy Space Center in Florida to bring astronauts Neil Armstrong, Mike Collins and Buzz Aldrin to the Moon. Neil Armstrong and Buzz Aldrin walked the surface of the Moon with Armstrong creating the first footprints on the Moon. Mike Collins' job was to keep Command Service Module Columbia in orbit around the Moon while the landing module Eagle would land.
A total of 12 humans were landed on the Moon because of the Apollo program. The technology, instruments and methods used during the missions were later used in robotic space probes. Thanks to Apollo, much of what we know about the Moon's geology is due to more than 841 pounds of lunar samples that were brought back, including Moon rocks, bags of dust and core samples. We learned that the Moon as its own history of volcanic activity, Moonquakes and meteorite impact. We have even been able to compare the ages of the Moon's youngest rocks with that of the Earth's oldest rocks. While the Moon does not have what is needed for an atmosphere or surface water to sustain life at least life can visit there! Following Apollo NASA wanted spacecrafts to go beyond the Moon in exploration of the planets, but because of the expense, the visits were canceled. The expense was not the only challenge presented. We have yet to know how to successfully shield astronauts from radiation during the missions. Additionally, the distance of the planets from Earth added its own obstacles.
From the Moon to Mars
In an attempt to continually comprehend the awesomeness of the universe, the space race needed to go on, so space probes that were also an orbiter were designed to withstand the obstacles. NASA's space probe, Mariner 9 however became the first spacecraft to orbit another planet, Mars. Because Mariner 9 was an orbiter it was able to wait out the wind and dust storms often produced there. Mariner 9's success taught us that there are volcanoes and canyons on Mars. Its remains of dry river channels and landslides also gave us the idea that there may have been water that flowed there. This sparked NASA to send missions to explore the possibility of life there. The Viking Project was designed for this exploration. It was created to map the surface of Mars from space, while landers could look for life on the ground. Scientific instruments and experiments measured the weather and temperature. Evidence of lakes and rivers that had gone dry were noted. The polar ice cap on Mars was confirmed to have been made from water rather than carbon dioxide and the element nitrogen was found in Mars' atmosphere.
The region visited by the Viking spacecraft proved Mars to be lifeless, but also gave birth to new questions for scientists. Our Earth and Mars seemed to have started from the same material, but overtime evolved into two very different worlds and scientists were left with questions as to why. Mars was seen as a cold desert with below freezing temperatures. Its atmosphere consists of mostly carbon dioxide. Because Mars is tilted it has seasons. It is a rocky planet with canyons, and plains and the soil on Mars is colored red from iron oxide. This red dust in the air makes the planet appear pink or reddish in the sky giving Mars, the nickname The Red Planet. It has two Moons. Since the Viking Project NASA has received images and data from Mars via the Mars Global Surveyor, Mars Pathfinder and Sojourner the Mars rover. The Mars Odyssey began to map the surface of Mars in 2001, while NASA's Mars Exploration Rovers, Spirit and Opportunity study the planets geology, giving evidence to ancient surface water. In 2006 Mars Reconnaissance Orbiter began scanning for water on Mars.
From Galileo's telescopes to human spaceflight, space probes, rovers and orbiters we have learned allot about our solar system. More than 50 missions have visited and studied the planets. So what is next for NASA? Another trip to the Moon? Human spaceflight to Mars? In 2004, United States president, George W. Bush suggested in a State of the Union address, that NASA plan another trip to the Moon in order to pave the way to a manned mission to Mars by 2030. A trip to Mars is a fifty million mile long journey which would take today's space craft up to nine months to even reach The Red Planet. This would be a very long journey for astronauts to sustain. Although floating in space appears to be fun, it is often hard on the human body. Astronauts suffer from backaches and stomachaches from their bones and organs moving within them. Living and working in a small cramped space for an approximately 2 year round trip mission would carry the weight of many physical and mental problems. In an attempt to make a trip to Mars a reality, exercise, medications and certain nutrients that astronauts would be given are being examined. Currently, the Mars Science Laboratory, a rover, is scheduled to land on Mars in 2010 and stay for at least one Martian year (687 Earth days). Its mission is to search for fossil or living signs of life. It is scheduled to return by 2014 with rock and soil samples getting NASA one step closer to human planetary exploration. The Mars Exploration Program is designed to determine if life had ever arisen on Mars, characterize its climate and geology and prepare for human exploration. In order to help make this dream a reality, NASA is in search of budding scientists and astronauts.