SatelliteA transponders is capable of : When satellites reach the end of their mission, satellite operators have the option of de-orbiting the satellite, leaving the satellite in its current orbit or moving the satellite to a graveyard orbit. Satellite subsystems attend many tasks, such as power generation, thermal control, telemetry, attitude control and orbit control. The first fictional depiction of a satellite being launched into orbit is a short story by Edward Everett Hale, The Brick Moon.
The unanticipated announcement of Sputnik 1 s success precipitated the Sputnik crisis in the United States and ignited the so-called Space Race within the Cold War. Sputnik 2 was launched on November 3, 1957 and carried the first living passenger into orbit, a dog named Laika. In May, 1946, Project RAND had released the Preliminary Design of a Experimental World-Circling Spaceship, which stated, A satellite vehicle with appropriate instrumentation can be expected to be one of the most potent scientific tools of the Twentieth Century. On July 29, 1955, the White House announced that the U.S. Satellite orbits vary greatly, depending on the purpose of the satellite, and are classified in a number of ways.
He also suggested that three geostationary satellites would provide coverage over the entire planet. The first artificial satellite was Sputnik 1, launched by the Soviet Union on 4 October 1957, and initiating the Soviet Sputnik program, with Sergei Korolev as chief designer and Kerim Kerimov as his assistant. Common types include military (spy) and civilian Earth observation satellites, communication satellites, navigation satellites, weather satellites, and research satellites.
It is common on commercial satellite space for earth stations to transmit at the wrong time or on the wrong frequency and dual illuminate the transponder rendering the frequency unusable. Launched in 1958, Vanguard 1, the 4th manmade satellite put in Geocentric orbit, was still in orbit as of August 2009. Instead of being de-orbited, most satellites are either left in their current orbit or moved to a graveyard orbit. This list includes countries with an independent capability to place satellites in orbit, including production of the necessary launch vehicle.
The SSN currently tracks more than 8,000 man-made orbiting objects. Such jamming is limited to the geographical area within the transmitter s range.
The SSN tracks space objects that are 10 centimeters in diameter (baseball size) or larger. There are three basic categories of non-military satellite services: Fixed satellite services handle hundreds of billions of voice, data, and video transmission tasks across all countries and continents between certain points on the earth’s surface. Mobile satellite systems help connect remote regions, vehicles, ships, people and aircraft to other parts of the world and/or other mobile or stationary communications units, in addition to serving as navigation systems. Scientific research satellites provide us with meteorological information, land survey data (e.g., remote sensing), Amateur (HAM) Radio, and other different scientific research applications such as earth science, marine science, and atmospheric research. The first satellite, Sputnik 1, was put into orbit around Earth and was therefore in geocentric orbit. He calculated the orbital speed required for a minimal orbit around the Earth at 8 km/s, and that a multi-stage rocket fueled by liquid propellants could be used to achieve this.
These originate from more than 50 countries and have used the satellite launching capabilities of ten nations. Russia, the United States and China have demonstrated the ability to eliminate satellites. Due to the low received signal strength of satellite transmissions they are prone to jamming by land-based transmitters.
~560 satellites), the rest are space debris. The project succeeded, and Explorer 1 became the United States first satellite on January 31, 1958. In June 1961, three-and-a-half years after the launch of Sputnik 1, the Air Force used resources of the United States Space Surveillance Network to catalog 115 Earth-orbiting satellites. The largest artificial satellite currently orbiting the Earth is the International Space Station. The United States Space Surveillance Network (SSN) has been tracking space objects since 1957 when the Soviets opened the space age with the launch of Sputnik I.
Low Earth orbit is any orbit below 2000 km, and Medium Earth Orbit is any orbit higher than that but still below the altitude for geosynchronous orbit at 35786 km. Since then, the SSN has tracked more than 26,000 space objects orbiting Earth.
Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon. The first artificial satellite, Sputnik 1, was launched by the Soviet Union in 1957. Historically, due to budgetary constraints at the beginning of satellite missions, satellites were rarely designed to be de-orbited.
intended to launch satellites by the spring of 1958. By 2009 thousands of satellites had been launched into orbit around the Earth.
The idea surfaces again in Jules Verne s The Begum s Fortune (1879). In 1903 Konstantin Tsiolkovsky (1857–1935) published The Exploration of Cosmic Space by Means of Reaction Devices (in Russian: Исследование мировых пространств реактивными приборами), which is the first academic treatise on the use of rocketry to launch spacecraft. He conceived of a space station in detail and calculated its geostationary orbit.
By far this is the most common type of orbit with approximately 2456 artificial satellites orbiting the Earth. The book described geostationary satellites (first put forward by Tsiolkovsky) and discussed communication between them and the ground using radio, but fell short of the idea of using satellites for mass broadcasting and as telecommunications relays. In a 1945 Wireless World article the English science fiction writer Arthur C.
Satellite operators now have sophisticated monitoring that enables them to pin point the source of any carrier and manage the transponder space effectively. . In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavor.
Geocentric orbits may be further classified by their altitude, inclination and eccentricity. The commonly used altitude classifications are Low Earth Orbit (LEO), Medium Earth Orbit (MEO) and High Earth Orbit (HEO). The space objects now orbiting Earth range from satellites weighing several tons to pieces of spent rocket bodies weighing only 10 pounds.
Note that some novel architectural concepts such as Fractionated Spacecraft somewhat upset this taxonomy. This bus module consist of the following subsystems: The structural subsystem provides the mechanical base structure, shields the satellite from extreme temperature changes and micro-meteorite damage, and controls the satellite’s spin functions. The telemetry subsystem monitors the on-board equipment operations, transmits equipment operation data to the earth control station, and receives the earth control station’s commands to perform equipment operation adjustments. The power subsystem consists of solar panels and backup batteries that generate power when the satellite passes into the earth’s shadow. Clarke examined the logistics of satellite launch, possible orbits and other aspects of the creation of a network of world-circling satellites, pointing to the benefits of high-speed global communications.
GPS satellites are potential targets for jamming, It is trivial to transmit a carrier to a geostationary satellite and thus interfere with any other users of the transponder. Clarke (1917-2008) described in detail the possible use of communications satellites for mass communications.
High Earth Orbit is any orbit higher than the altitude for geosynchronous orbit. The satellite’s functional versatility is imbedded within its technical components and its operations characteristics. On July 31, the Soviets announced that they intended to launch a satellite by the fall of 1957. Following pressure by the American Rocket Society, the National Science Foundation, and the International Geophysical Year, military interest picked up and in early 1955 the Air Force and Navy were working on Project Orbiter, which involved using a Jupiter C rocket to launch a satellite.
This became known as Project Vanguard. He described the use of orbiting spacecraft for detailed peaceful and military observation of the ground and described how the special conditions of space could be useful for scientific experiments.
The story is serialized in The Atlantic Monthly, starting in 1869. Optical Solar Reflector) The attitude and orbit controlled subsystem consists of small rocket thrusters that keep the satellite in the correct orbital position and keep antennas positioning in the right directions. The second major module is the communication payload, which is made up of transponders.
Nuclear power sources (Radioisotope thermoelectric generators) have been used in several successful satellite programs including the Nimbus program (1964-1978). The thermal control subsystem helps protect electronic equipment from extreme temperatures due to intense sunlight or the lack of sun exposure on different sides of the satellite’s body (e.g. This list does not consider those numerous countries, but only lists those capable of launching satellites indigenously, and the date this capability was first demonstrated.
Well-known (overlapping) classes include low Earth orbit, polar orbit, and geostationary orbit. Satellites are usually semi-independent computer controlled systems. A few space probes have been placed into orbit around other bodies and become artificial satellites to the Moon, Venus, Mars, Jupiter and Saturn. Satellites are used for a large number of purposes.
This in turn triggered the Space Race between the Soviet Union and the United States. Sputnik 1 helped to identify the density of high atmospheric layers through measurement of its orbital change and provided data on radio-signal distribution in the ionosphere. About seven percent of the space objects are operational satellites (i.e.
A few hundred satellites are currently operational, whereas thousands of unused satellites and satellite fragments orbit the Earth as space debris. This marked the first time that a privately built liquid-fueled booster was able to reach orbit. While Canada was the third country to build a satellite which was launched into space, In recent times satellites have been hacked by militant organizations to broadcast propaganda and to pilfer classified information from military communication networks. Satellites in low earth orbit have been destroyed by ballistic missiles launched from earth.
He proposed the use of liquid hydrogen and liquid oxygen, though other combinations can be used. In 1935 Slovenian Herman Potočnik (1930–1996) published his sole book, The Problem of Space Travel — The Rocket Motor (German: Das Problem der Befahrung des Weltraums — der Raketen-Motor), a plan for a breakthrough into space and a permanent human presence there. USSTRATCOM is primarily interested in the active satellites, but also tracks space debris which upon reentry might otherwise be mistaken for incoming missiles.
The rest have re-entered Earth s atmosphere and disintegrated, or survived re-entry and impacted the Earth. Because the satellite s body was filled with pressurized nitrogen, Sputnik 1 also provided the first opportunity for meteoroid detection, as a loss of internal pressure due to meteoroid penetration of the outer surface would have been evident in the temperature data sent back to Earth.
Space stations and human spacecraft in orbit are also satellites. Looking at the “anatomy” of a typical satellite, one discovers two modules.
Note: many more countries have the capability to design and build satellites — which relatively speaking, does not require much economic, scientific and industrial capacity — but are unable to launch them, instead relying on foreign launch services. One example of this practice is the satellite Vanguard 1.
Does not include consortium satellites or multi-national satellites. On September 28, 2008, the private aerospace firm SpaceX successfully launched its Falcon 1 rocket in to orbit.