DAFINE SATELITE AND ENUMERATE IT FUNCTION In general, a satellite is anything that orbits something else, as, for example, the moon orbits the earth. In a communications context, a satellite is a specialized wireless receiver/transmitter that is launched by a rocket and placed in orbit around the earth. There are hundreds of satellites currently in operation. They are used for such diverse purposes as weather forecasting, television broadcast, amateur radio communications, Internet communications, and the Global Positioning System, (GPS). Or it could also be defined as: A satellite is a moon, planet or machine that orbits a planet or star. For example, Earth is a satellite because it orbits the sun. Likewise, the moon is a satellite because it orbits Earth. Usually, the word "satellite" refers to a machine that is launched into space and moves around Earth or another body in space. FUNCTIONS OF SATELITE Weather • Weather satellites send down a constant stream of data, reporting to us myriad facts from around the globe. Information beamed down includes temperature, rainfall, wind speed, and cloud patterns. Meteorologists use this information to help them predict the weather, especially in spotting severe storms before they become dangerous. This gives people a chance to take shelter from tornadoes and evacuate areas in the path of hurricanes. Exploration • Another important function of satellites is to explore and map the Earth and other planets. Many satellites are equipped with cameras that capture still and video pictures of the surface of the planet. Infrared images, showing patterns of heat and cold, are also common. Scientists use satellite images to track changes in hard-to-reach places, such as the polar ice caps. The Hubble satellite orbits the earth, but has its cameras pointed at the stars. Being positioned in space allows it to transmit images that are not affected by the Earth's atmosphere. The pictures of stars and nebulae are studied by astronomers, but they are also made available to the general public through a variety of outlets, such as the Hubble Gallery on the Wired Science website. In 2009, Google Earth added a feature allowing users to explore the surface of Mars using maps from sources such as the Mars Reconnaissance Orbiter, a satellite project of NASA. Satellites can be divided into six principal types based on their functions i.e. (i) Research (ii) Communications (iii) Weather (iv) Navigation (v) Applications and (vi) Military satellites (I) Research satellites: These measure fundamental properties of outer space, e.g., magnetic fields, the flux of cosmic rays and micrometeorites, and properties of celestial objects that are difficult or impossible to observe from the earth. Early research satellites included a series of orbiting observatories designed to study radiation from the sun, light and radio emissions from distant stars, and the earth's atmosphere. Notable research satellites have included the Hubble Space Telescope , the Compton Gamma-Ray Observatory, the Infrared Space Observatory, and the Solar and Heliospheric Observatory. (ii) Communications satellites: These provide a worldwide linkup of radio, telephone, and television. The first communications satellite was Echo 1, launched in 1960. Relay 1 and Telstar 1, both launched in 1962, were the first active communications satellites; Telstar 1 relayed the first live television broadcast across the Atlantic Ocean. In principle, these can provide complete coverage of the earth's surface, instantaneous communications throughout the world and a variety of telecommunications tasks. • A communications satellite is one that serves as a relay for signals from one point on the ground to another. These satellites are typically geosynchronous, which means they are placed into orbit in such a way that they are always over the same spot on the earth. Communications satellites handle telephone signals, mobile communications, and ship-to-shore radio. They also relay television and radio signals from the broadcast point to stations around the country. (III) WEATHER SATELLITES OR METEOROLOGICAL SATELLITES: These provide continuous, up-to-date information about large-scale atmospheric conditions such as cloud cover and temperature profiles. Tiros 1, the first such satellite, was launched in 1960; it transmitted infrared television pictures of the earth's cloud cover and was able to detect the development of hurricanes and to chart their paths. Current weather satellites can transmit visible or infrared photos, focus on a narrow or wide area, and maneuver in space to obtain maximum coverage. (IV) NAVIGATION SATELLITES: These were developed primarily to satisfy the need for a navigation system that nuclear submarines could use to update their inertial navigation system. This led the U.S. navy to establish the Transit program in 1958. Transit satellites provided a constant signal by which aircraft and ships could determine their positions with great accuracy. It provides greater accuracy in a shorter time; users can obtain information 24 hours a day. These satellites were of enormous help to transportation companies, especially transportation over water and through the air.Navigation satellites are also used for distance measurements for instance between buildings. (V) APPLICATIONS SATELLITES: These are designed to test ways of improving satellite technology itself. Areas of concern include structure, instrumentation, controls, power supplies, and telemetry for future communications, meteorological, and navigation satellites. (VI) MILITARY SATELLITES Satellites also have been used for a number of military purposes, including infrared sensors that track missile launches; electronic sensors that eavesdrop on classified conversations; and optical and other sensors that aid military surveillance. These are Very similar to weather satellites but generally with higher resolution cameras and instead of normal communications equipment, they use encryption as well. WRITE THE HISTORICAL DEVELOPMENT AND FUNCTION OF NIGERIAN SATI AND SAT IINICOMSAT • The National Space Research and Development Agency (NASRDA) is the national space agency of Nigeria. It is a part of the Federal Ministry of Science and Technology and it is overseen by the National Council on Space Science Technology. The Agency based in the Nigerian capital Abuja has a ground receiving station. Nigeria has cooperation in space technology with the United Kingdom, China, Ukraine and Russia. History NASRDA was established in 1 August 2001 after preparation period since in 1998 by Nigerian president Olusegun Obasanjo and the Nigerian government with a primary objective of establishing a "fundamental policy for the development of space science and technology" with an initial budget of $93 million. In May 2006, the new extended national space program was adopted. There is no nation in the world that can develop without the development of its science and technology. In recognition of this, Nigeria last week went to the space , launching two satellites into the orbit. The history of satellites started in Nigeria in 1976, when the then Head of State made it known to Economic Council of Africa/Organization of Africa Union (ECA/OAU ), member countries at an inter-government meeting in Addis-Ababa. The Federal Government between 1976 and 1980, made a development plan to invest the sum of N10 million. After considering much policies, the Federal Ministry of Science and Technology that was formally a council in 1970 became a fully fledged ministry in 1980 and thereafter, the National Space Research and Development Agency was carved out of the ministry in 1988. Federal Government launched the first satellite, NigSat-1, into the orbit on September 26th, 2003 in Plestek, Russia after some experts have undergone training at Surrey Satellite Technology in London. NigeriaSat-1 is one of the five disaster monitoring satellites that form a network called the Disaster Monitoring Constellation and by so will share information with each other when disaster monitoring is needed. That first satellite (Sat – 1), was supposed to last for five years but it is still working in the orbit but the second communication satellite (Nigcomsat) that was launched in May 2007 got lost due a cut to the fuel supply link of the panel resulting in a solar flare. But Nigcomsat – would be replaced at the end of the year because according to a source it is about 75% completed. The launched of Nigsat – 2 and Nigsat – X on Wednesday 17th August, 2011, at exactly 8:12am local time was strategic for the nation and the global community. The launch which was done in Yasny which is about two hours flight from the Russian capital, marked another important feat for Nigeria. Also, the fact that Nigsat – X was solely built and designed by Nigerian Engineers and has a 2.5 meter high spatial resolution sensor as a strength point was another added advantage. The satellites can be used for demography, like mapping and planning of population survey, census enumeration areas, mapping, planning and monitoring of rural and urban growth and also give advance warnings of natural disasters like floods, earthquakes, volcanic eruptions and storms. Nigeria can use Sat – 2 and Sat – X to mange oil pollutions, desertification, erosion, forest fire and deforestation. It will also be used for mapping, land use planning, and management of sustainable gazing, forest logging, planning afforestation programmes, crop inventory and yield forecast. Flaunting the achievement of HIS Agency in launching the satellites, Head, media and corporate affairs of the National Space Research and Development Agency (NASDA), Mr. Felix Ale said, “the two spacecrafts were integrated on the launch vehicle. NigeriaSat-2 after its launch will be the most advanced satellite of its kind in the global community. The imaging mode is unique, due to the agility of the spacecrafts. “The satellites will allow imaging in the various modes, and pave way for data sets for more applications which are not possible with most satellites of its kind. The launch of NigeriaSat-2 and NigeriaSat-X is expected to provoke data revolution of high resolution in Nigeria and indeed all Africa” he added. The data from the two satellites can be used in agriculture, forestry, land use and mapping, environmental and disaster monitoring, mitigation and management, geological mapping and transportation. Scope The initial scope of the Nigerian Space Programme (NSP) to be implemented by the National Space Research and Development Agency (NASRDA) should include: The study of basic space science in order to lay the foundation for deriving maximum benefits from the nation’s participation in the space enterprise; For the attainment of space capabilities, Nigeria’s efforts should focus on research and rigorous education, engineering development, design and manufacture, particularly in the areas of instrumentation, rocketry and small satellites as well as in satellite data acquisition, processing, analysis and management of related software; The establishment of a national earth observation station for remote sensing and satellite meteorology data acquisition. Such an infrastructure will enhance the indigenous ability to adopt, modify and create new techniques for national resources inventories, monitoring, evaluation and management; The provision of efficient, reliable and adequate telecommunications services in Nigeria in order to enhance the growth of the industrial, commercial and administrative sectors of the economy. The focus areas of the National Space Programme (NSP) include: Basic Space Science and Technology to provide the understanding of how the universe works and what its impact is on the world. This will enable us to lay the foundation for deriving maximum benefits from the nation’s participation in the space enterprise. Remote sensing to help Nigerians understand and manage our environment and natural resources using space-acquired information. This technology will enable us to better understand our land, air and water resources and their associated problems. Satellite Meteorology to study atmospheric and weather sciences using satellite data to facilitate the effective management of our environment. Communication and Information Technology to provide efficient and reliable telecommunications services for Nigeria in order to enhance the growth of the industrial, commercial and administrative sectors of the economy.