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Batteries In Space
Batteries are used on spacecraft as a means of power storage. Primary batteries contain all their usable energy when assembled and can only be discharged. Secondary batteries can be recharged from some other energy source, such as solar panels or radioisotope-based power ( RTG), and can deliver power during periods when the space vehicle is out of direct sunlight. Batteries generate electrical current from a chemical reaction. Batteries for spacecraft must be sealed to operate in vacuum. They must withstand the acceleration of launch, and vibration while attaining orbit. They must be able to operate over a wide temperature range, and must not emit gases that would corrode the space vehicle, disturb its trajectory, or contaminate instruments or life support systems. Batteries for vehicles orbiting the Earth must also resist the high ionizing radiation level above the shield of the Earth's atmosphere. Artificial satellites, such as communication satellites, require battery sys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Events January–March * January – **Benito Juárez (1806–1872) becomes Liberal President of Mexico. At the same time, conservatives install Félix María Zuloaga (1813–1898) as president. **William I of Prussia becomes regent for his brother, Frederick William IV, who had suffered a stroke. * January 9 ** British forces finally defeat Rajab Ali Khan of Chittagong ** Anson Jones, the last president of the Republic of Texas, commits suicide. * January 14 – Orsini affair: Felice Orsini and his accomplices fail to assassinate Napoleon III in Paris, but their bombs kill eight and wound 142 people. Because of the involvement of French émigrés living in Britain, there is a brief anti-British feeling in France, but the emperor refuses to support it. * January 25 – The ''Wedding March'' by Felix Mendelssohn becomes a popular wedding recessional, after it is played on this day at the marriage of Queen Victoria's daughter Victoria, Princess Royal, to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battery (electricity)
An electric battery is a source of electric power consisting of one or more electrochemical cells with external connections for powering electrical devices. When a battery is supplying power, its positive terminal is the cathode and its negative terminal is the anode. The terminal marked negative is the source of electrons that will flow through an external electric circuit to the positive terminal. When a battery is connected to an external electric load, a redox reaction converts high-energy reactants to lower-energy products, and the free-energy difference is delivered to the external circuit as electrical energy. Historically the term "battery" specifically referred to a device composed of multiple cells; however, the usage has evolved to include devices composed of a single cell. Primary (single-use or "disposable") batteries are used once and discarded, as the electrode materials are irreversibly changed during discharge; a common example is the alkaline battery use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radioisotope Thermoelectric Generator
A radioisotope thermoelectric generator (RTG, RITEG), sometimes referred to as a radioisotope power system (RPS), is a type of nuclear battery that uses an array of thermocouples to convert the heat released by the decay of a suitable radioactive material into electricity by the Seebeck effect. This type of generator has no moving parts. RTGs have been used as power sources in satellites, space probes, and uncrewed remote facilities such as a series of lighthouses built by the Soviet Union inside the Arctic Circle. RTGs are usually the most desirable power source for unmaintained situations that need a few hundred watts (or less) of power for durations too long for fuel cells, batteries, or generators to provide economically, and in places where solar cells are not practical. Safe use of RTGs requires containment of the radioisotopes long after the productive life of the unit. The expense of RTGs tends to limit their use to niche applications in rare or special situations. B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionizing Radiation
Ionizing radiation (or ionising radiation), including nuclear radiation, consists of subatomic particles or electromagnetic waves that have sufficient energy to ionize atoms or molecules by detaching electrons from them. Some particles can travel up to 99% of the speed of light, and the electromagnetic waves are on the high-energy portion of the electromagnetic spectrum. Gamma rays, X-rays, and the higher energy ultraviolet part of the electromagnetic spectrum are ionizing radiation, whereas the lower energy ultraviolet, visible light, nearly all types of laser light, infrared, microwaves, and radio waves are non-ionizing radiation. The boundary between ionizing and non-ionizing radiation in the ultraviolet area is not sharply defined, as different molecules and atoms ionize at different energies. The energy of ionizing radiation starts between 10 electronvolts (eV) and 33 eV. Typical ionizing subatomic particles include alpha particles, beta particles, and neutrons. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communication Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The high frequency radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications sate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosynchronous Orbit
A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbital period means that, for an observer on Earth's surface, an object in geosynchronous orbit returns to exactly the same position in the sky after a period of one sidereal day. Over the course of a day, the object's position in the sky may remain still or trace out a path, typically in a figure-8 form, whose precise characteristics depend on the orbit's inclination and eccentricity. A circular geosynchronous orbit has a constant altitude of . A special case of geosynchronous orbit is the geostationary orbit, which is a circular geosynchronous orbit in Earth's equatorial plane with both inclination and eccentricity equal to 0. A satellite in a geostationary orbit remains in the same position in the sky to observers on the surface. Commu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Shuttle
The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was Space Transportation System (STS), taken from a 1969 plan for a system of reusable spacecraft where it was the only item funded for development. The first ( STS-1) of four orbital test flights occurred in 1981, leading to operational flights (STS-5) beginning in 1982. Five complete Space Shuttle orbiter vehicles were built and flown on a total of 135 missions from 1981 to 2011. They launched from the Kennedy Space Center (KSC) in Florida. Operational missions launched numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST), conducted science experiments in orbit, participated in the Shuttle-''Mir'' program with Russia, and participated in construction and servicing of the International Space Station (IS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuel Cell
A fuel cell is an electrochemical cell that converts the chemical energy of a fuel (often hydrogen fuel, hydrogen) and an oxidizing agent (often oxygen) into electricity through a pair of redox reactions. Fuel cells are different from most battery (electricity), batteries in requiring a continuous source of fuel and oxygen (usually from air) to sustain the chemical reaction, whereas in a battery the chemical energy usually comes from substances that are already present in the battery. Fuel cells can produce electricity continuously for as long as fuel and oxygen are supplied. The first fuel cells were invented by Sir William Robert Grove, William Grove in 1838. The first commercial use of fuel cells came more than a century later following the invention of the hydrogen–oxygen fuel cell by Francis Thomas Bacon in 1932. The alkaline fuel cell, also known as the Bacon fuel cell after its inventor, has been used in NASA space programs since the mid-1960s to generate power for sat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reserve Battery
A reserve battery, also called stand-by battery, is a primary battery where part is isolated until the battery needs to be used. When long storage is required, reserve batteries are often used, since the active chemicals of the cell are segregated until needed, thus reducing self-discharge. A reserve battery is distinguished from a backup battery, in that a reserve battery is inert until it is activated, while a backup battery is already functional, even if it is not delivering current. Uses These batteries are used in radiosondes, missiles, projectile and bomb fuzes, and various weapon systems. While not advertised as reserve batteries, the principle is illustrated by the sale of "dry charged" car batteries where the electrolyte is added at the time of sale. Another example is zinc-air batteries where the cell is sealed until use: a tab is removed to admit air and activate the cell. Activation Reserve batteries may be activated by addition of water, by adding electrolyte, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Spacecraft Powered By Non-rechargeable Batteries
This is a list of spacecraft powered by non-rechargeable batteries. While most spacecraft are powered by longer-lasting power sources such as solar cells or radioisotope thermoelectric generators, which can provide power for years to decades, some have been powered by primary (non-rechargeable) electrochemical cells, which provide runtimes of minutes to months. This is typically done only on spacecraft that are planned to operate for only a short time, even if they must travel for a long time before being activated. Some spacecraft classes where this applies are atmospheric probes, short-duration landers, and technology demonstrators. Some early Earth satellites, such as the first Sputnik and Explorer satellites, also used primary batteries, before solar panels were widely adopted. Uncrewed Primary power comes from a chemical battery, but a secondary system exists. For example, Luna 9 ran out of power after three days. Crewed *early Gemini with on silver-zinc (Ag-Zn), la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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