1. Astronomy is the field of study about natural objects in the sky.
2. Ancient astronomers from the Middle East, China and India had made observations about the movements of the Sun, stars and Moon.
3. Ancient astronomers like the Greeks had tried to explain the movements of planets and stars.
ASTRONOMERS AND THEIR CONTRIBUTION TO THE FIELD OF ASTRONOMY
The first astronomer to suggest that the Earth rotates on its axis and moves following its own orbit.
Classified stars according to their brightness.
Developed theory about the Solar System.
Suggest that the Earth is the centre of the Solar System.
· Invented the first astronomical telescope and used it to observe :
(a) the Moon’s surface
(c) Saturn and its rings(d) the four moons that orbit Jupiter
Said that the Earth’s orbit is elliptical in shape.
Discovered Halley’s Comet (this comet is predicted to reappear every 76 years)
|Albert Einstein |
Advanced the idea about the relationship between time, space and energy.
First man to detect radio waves from outer space with radio telescope.
|Johann G. Galle|
|Clyde W. Tombaugh|
DEVELOPMENT IN SPACE EXPLORATION
1. Space exploration was first done from the Earth with the use of a telescope.
2. Rockets, man-made satellites, space stations and space shuttles were later invented to continue the efforts of space exploration.
APPLICATION OF TECHNOLOGY RELATED TO SPACE EXPLORATION AND ASTRONOMY
DATE OF EVENTS IN THE FIELD OF ASTRONOMY
16 March 1926
· Goddard launched the first fuel-propelled rocket to space.
4 October 1957
· The first man-made satellite, Sputnik 1, was launched into orbit around the Earth. This satellite did not carry any living thing.
3 November 1957
· Sputnik 2 was launched into the Earth’s orbit.
13 September 1959
· First spaceship, Lunar 2, was launched. However, this spaceship crashed onto the Moon’s surface 24 hours after the launch.
12 April 1961
· Yuri Gagarin, the first man in space in his spaceship to orbit.
27 August 1962
· First space probe, Mariner 2, was launched to Venus.
28 November 1964
· Second space probe, Mariner 4, was launched to Mars.
3 February 1966
· Soviet Union’s spaceship, Lunar 9, landed on the Moon’s surface. This spaceship did not carry any astronaut.
21 July 1969
· Neil Armstrong was the first astronaut to land on the Moon in the spaceship, Apollo 11.
· Pioneer 10 was launched to Jupiter.
· Pioneer 11 was launched to Saturn.
· Mariner 10 was launched to Mercury and Venus.
· Space station, Skylab, was launched to orbit the Earth.
· Viking 1 and Viking 2 landed on Mars.
· Space shuttle Columbia was launched.
· Voyager 2 moved across the space of Uranus.
· Voyager 2 moved across the space of Pluto.
25 April 1990
· Space shuttle, Discovery, carried five astronauts. The Hubble telescope was placed in the Earth’s orbit to gather information about the galaxies.
25 September 1992
· Spaceship Mars Observer orbited Mars.
APPLICATION OF TECHNOLOGY RELATED TO SPACE EXPLORATION AND ASTRONOMY
A few types of modern technological instrument have been invented for outer space exploration. Among them are the :
(c) space station
(e) space shuttle
There are three types of telescope used for outer space exploration, i.e. :
(a) refracting telescope
(b) reflecting telescope
(c) radio telescope
A reflecting telescope uses mirrors to take and send photographs on outer space.
A radio telescope is used to receive electric signals and radiation from outer space.
Today, astronomical telescope like the Hubble telescope are used to observe the galaxies.
1. Spaceship have been launched into outer space to obtain various information.
2. Spaceship that carry astronaut are launched by rockets into outer space.
3. A probe is a spaceship that does not carry humans. Examples of space probes are Voyager 2, Viking 1, Pioneer 10 and Mariner 10.
4. Space probes are launched to collect information by taking photograph of our Solar System. Then, the information is sent back to Earth in the form of radio signals and received on Earth through radio telescopes.
1. A space station provides a place in space that enables astronauts to carry out research while in outer space.
2. Russia’s space station, Salyut, and America’s space station, Skylab, were launched for this purpose.
|International Space Station|
3. The International Space Station is a space station which is now being built in orbit through the co-operation of 16 countries.
ROCKETS1. Rockets are used to launch objects like spaceships or probes and satellites.
2. Rockets cannot be used repeatedly. Today, the roles of rockets have eventually been replaced by space shuttles.
SPACE SHUTTLE1. Such a spaceship can be launched, return to Earth and be used repeatedly.
2. Nowadays, the launching of spaceships with rockets have been replaced by space shuttles.
3. The space shuttle is used to :
(a) carry astronauts and research equipment
(b) launch probes
(c) launch satellites
(d) bring back or repair satellites that have malfunctioned in space
4. For example, the spaceship Discovery was used to launch a satellite into its orbit.
1. A satellite is an object that moves around another object in a certain orbit.
2. The man-made satellite, Sputnik 1, was launched into space by the Russians in 1957. Since then, hundreds of such satellites have been launched.
3. Man-made satellites have been launched into certain orbits to play a role in remote sensing.
4. Satellites that have been launched have brought benefits to humans especially in the field of :
(g) disaster management
(h) national security management
(a) A communications satellites is a satellite that is able to send information through televisions, radios, telephones, telexes, the Internet etc. to the whole world very quickly.
(b) This type of satellite overcomes barriers like oceans, mountain ranges and deserts.
(c) A communications satellite enables us to receive live radio and television broadcasts and receive information through telegraphs, telexes, telephones, fax machines, the Internet etc.
(d) A communications satellite is launched to orbit the Earth. Signals transmitted from one place on Earth are reflected by the satellite back to another place on Earth that wants to receive them.(e) As an example, the Intelsat satellite located at the Atlantic Ocean, the Indian ocean and the Pacific Ocean connects the whole world.
(a) This type of satellite helps us to forecast weather conditions accurately.
(b) This type of satellite can detect changes of temperature, wind and pressure in the atmosphere.
(c) Information received from this satellite can help us in forecasting the place and time typhoons, floods, cyclones as well as high tide and low tide will happen.
(d) This satellite can take photographs such as clouds, ice and snow and send them through signals to meteorological stations on Earth.
(e) With this facility, an early warning can be given and steps can be taken to overcome or avoid possible disasters.
(f) Accurate weather forecast enable engineers to plan the best time to carry out big projects like building bridges, highways and dams.
(a) A navigational satellite helps ships and aeroplanes to plot their positions accurately, especially during bad weather.
(b) The satellite that receives an emergency signal can quickly and accurately relay signal to a rescue crew of the exact position of the victims.
(c) This satellite also helps sailing ships to identify the positions of icebergs and the occurrence of ocean currents.
(a) Satellite can help geologist to explore for oil and certain minerals.
(b) By studying photographs taken from a satellite, geologist can detect the existence of natural resources like petroleum, coal and metal ore beneath the surface of the Earth.
(a) A satellite can be used to detect agricultural land that will be suitable for certain crops.
(b) By taking photographs, a satellite can identify the type of crops found in a certain cultivated region.
(c) A satellite can also give information to farmers about cultivated regions that have been infected by a certain disease. With this information, steps can be taken quickly to control the problem.
(d) A satellite can help farmers to control irrigation and forecast drought.
(e) A satellite can detect the overflow of a river that causes flood. This enables farmers to take steps to overcome it.
(f) Weather forecast enable farmers to determine the time to plant of harvest their crops as well as to avoid their crops from being destroyed by snow or hail.
(g) This type of satellite plays an important role in determining the distribution of crops and how factors like air humidity, planting season, sunlight, temperature, type of soil, condition of irrigation and air pollutants affect the growth of crops.
(a) A satellite can give information about the productivity of forests and grassland, conditions of wildlife habitat, use of forest land, logging management, and places suitable for recreation. Therefore, protection of forest for the future can be planned.
(b) A satellite can help to determine the quantity of logs that can be cut down from certain forest areas.
(c) Apart from this, a satellite can also give information about the destruction of forest as a result of fire, pests or disease.
(a) A satellite enables us to manage the occurrence of natural disasters like typhoons and drought in a certain region.
(b) Early warning can be given to residents in the affected areas. With this, early steps can be taken to overcome the problem.
NATIONAL SECURITY MANAGEMENT
(a) A satellite can detect pollution like oil spills in the sea.
(b) A satellite can also detect occurrences like the thinning of the ozone layer in certain regions and global warming caused by the greenhouse effect.
(c) With this, early warning can be given and steps taken to overcome the problem.
(d) A satellite can help certain parties to observe enemy troops and their movement.
THE NEED TO CONTINUE SPACE EXPLORATION
(a) To expose the secrets of Earth, the planets and other space objects that have remained unknown all this while.
(b) To obtain minerals like aluminium, potassium, magnesium and iron found on the Moon, other planets or asteroids.
(c) To search for new settlements for humans on the Moon, other planets or in space.
(d) To study the setting up of power stations in space using solar energy. The solar energy obtained can then be sent back to Earth.