SPACE EXPLORATION

DEVELOPMENT IN ASTRONOMY

Ancient Arabs	Used the stars to guide them in long journeys across the deserts. They stated that one month consists of 30 days.
Ancient Chinese	Named some constellations after animals and their gods. They were able to predict eclipses of the Sun and the Moon.
Priests in India	Made and recorded very careful observations on stars and planets. They believed that the lives of human beings were influenced by heavenly bodies.
Pythagoras (582-500 BC)	Stated that the Earth was a sphere. It looked flat because it was very large.
Aristotle (384-322 BC)	Also stated the Earth was spherical but he believed that the Earth was the centre of the Universe and that the Sun and planets were orbiting it.
Claudius Ptolemy (100-170)	Believed that the Earth was the centre of Solar System and that the Sun, the Moon and planets orbiting the Earth Each planet also moved around its own orbit. The stars were situated on a sphere far away from the planets. The stars moved across the sky when the sphere turned.
Al-Batani (858-929)	Used mathematical principle such as trigonometry and logarithms in the study of astronomy.
Nicholas Copernicus (1473-1543)	Suggested that the Sun was the centre of the Solar System, not Earth. He wrote a book on this theory.
Galileo Galilei (1564-1642)	Supported Copernics' theory. His observation of the four moons of Jupiter using his first self-made telescope confirmed for him that Copernicus' theory was correct. He also used his telescope to observe the Moon's surface and sunspots on the Sun.
Johannes Kepler (1571-1630)	Showed that the orbits of planets were elliptical and not circular as was widely believed.
Isacc Newton (1642-1727)	Discovered the law of gravity. Explained that the planets were kept in their orbits by the force of gravity of the Sun.
Edmond Halley (1656-1742)	Predicted that the comet seen in 1682 would return in 1758. His prediction is true and the comet was later named Halley's Comet.
William Herschel (1738-1822)	Discovered planet Uranus in 1781.
Johann G. Galle (1812-1910)	Discovered planet Neptune in 1848.
Albert Einstein (1879-1955)	Famous for his theory of relativity which changed the ideas of time, space and energy.
Edwin Hubble (1889-1953)	Proved the existence of galaxies and suggested that the Universe was made up of galaxies.
Clyde W. Tombaugh (1906-1997)	Discovered planet Pluto when he was only 24 years old.

ACHIEVEMENT IN SPACE EXPLORATION

Year	Achievements
1957 (October)	Sputnik I, the first man-made satellite, was launched into space by the Russians. It orbited the Earth.
1957 (November)	Sputnik II, with a dog in it, was launched into orbit. The satellite was burnt on entry into the Earth's atmosphere.
1959	Lunar 2, the first spaceship built by the Russians, was launch to photograph the surface of the Moon. The spaceship crashed on the Moon's surface.
1961	Major Yuri Gagarin became the first man to orbit the Earth in his spaceship. He returned safely to Earth 108 minutes after launching.
1965	Alexei A. Leonov became the first man to walk in space. He was attached, to his spaceship, Voskhod 2, by a gold-plated cable.
1966	Lunar 9, Russian spaceship. Successfully landed on the Moon. There was no astronaut on board.
1969 (21 July)	American astronaut, Neil Armstrong, landed on the Moon. He and his two companions returned safely to Earth on board Apollo 11.
1973	Skylab, the first space station, was sent into orbit by America.
1970-1989	Several spaceships were launched to study Mercury. Jupiter, Saturn, Uranus and Neptune. They sent back photographs and other information to Earth.
1990	The Discovery, America's first shuttle spaceship was launched. It carried 5 astronauts and placed Hubble Space Telescope in orbit. This telescope is still sending back photographs of distant galaxies.
2000	The International Space Station sponsored by 16 nations was launched. It is scheduled to be completed in 2006. It will have living accommodations, a power station and laboratories. It will be about the size of a football field when completed. It orbits the Earth every 90 minutes at a speed of 27,000 km/h and at altitude of 400 km.
2004 (July)	Cassini, a NASA spaceship, went into orbit around Saturn after travelling 7 years from the Earth. This probe will study the planets, its rings and its 31 known moons.
2005	International astronomers released an image of a giant planet observed outside our Solar System.

TECHNOLOGY USED IN SPACE EXPLORATION

• Space telescopes (Eg: Hubble Space Telescope)
• Radio telescopes
• Rockets
• Space shuttles (Eg: Columbia, Discovery)
• Satellites
• Spaceship and space probes
• Space station (Eg: Skylab, Mir, International Space Ship)

APPLICATION OF SPACE TECHNOLOGY

• Telecommunication
  • Receive signals from Earth, amplify them and send back to receiving stations on Earth.
• Weather forecasting
  • Detect changes in atmosphere (changes of temperature, atmospheric pressure, wind direction, clouds)
  • Information sent to meteorological stations on Earth
• Locating natural resources
  • Locate areas on Earth which are rich in minerals, petroleum, natural gas, metal ores
  • Shows areas suitable for growing crops and condition of forests
  • Detect oil spills on sea
• Navigation of ships and aeroplanes
  • Help sailor and pilots find their position by sending necessary information.
• National defence
  • Spy satellites are used to get information of foreign countries regarding their military capabilities.
• Alloy and medicine manufacturing
  • Certain medicines and alloys are best prepared in vacuum.
• Solar panels
  • Developed for spaceship to operate satellites
• Heat resistant materials
  • Developed for spaceships and now used in electronic industry.
• Photography techniques
  • Techniques and lenses developed for spaceships are now used in everyday cameras.