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Small Satellite
A small satellite, miniaturized satellite, or smallsat is a satellite of low mass and size, usually under . While all such satellites can be referred to as "small", different classifications are used to categorize them based on mass. Satellites can be built small to reduce the large economic cost of launch vehicles and the costs associated with construction. Miniature satellites, especially in large numbers, may be more useful than fewer, larger ones for some purposes – for example, gathering of scientific data and radio relay. Technical challenges in the construction of small satellites may include the lack of sufficient power storage or of room for a propulsion system. Rationales One rationale for miniaturizing satellites is to reduce the cost; heavier satellites require larger rockets with greater thrust that also have greater cost to finance. In contrast, smaller and lighter satellites require smaller and cheaper launch vehicles and can sometimes be launched in multip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estcube-1 2012-12-27
ESTCube-1 is the first Estonian satellite and first satellite in the world to attempt to use an electric solar wind sail (E-sail). It was launched on 7 May 2013 aboard Vega VV02 carrier rocket and successfully deployed into orbit. The CubeSat standard for nanosatellites was followed during the engineering of ESTCube-1, resulting in a 10×10×11.35 cm cube, with a volume of 1 liter and a mass of 1.048 kg. The mission ended officially on 17 February 2015 and it was said that during this time it resulted in 29 bachelor's and 19 master's dissertations, 5 doctoral theses and 4 start-ups. The deployment of the E-sail tether was unsuccessful, and thus no measurements were taken of the E-sail or of the plasma braking deployment system. The last signal from ESTCube-1 was received on 19 May 2015. Scientific purpose Developed as part of the Estonian Student Satellite Program, ESTCube-1 was an educational project in which university and high school students participated. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medium Earth Orbit
A medium Earth orbit (MEO) is an geocentric orbit, Earth-centered orbit with an altitude above a low Earth orbit (LEO) and below a high Earth orbit (HEO) – between above sea level.''Catalog of Earth Satellite Orbits'' NASA Earth Observatory. 4 September 2009. Accessed 2 May 2021. The boundary between MEO and LEO is an arbitrary altitude chosen by accepted convention, whereas the boundary between MEO and HEO is the particular altitude of a geosynchronous orbit, in which a satellite takes 24 hours to circle the Earth, the same period as the Earth’s own rotation. All satellites in MEO have an orbital period of less than 24 hours, with the minimum period (for a circular orbit at the lowest MEO altitude) about 2 hours. Satellites in MEO or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SSOT (satellite)
The Satellite System for Terrestrial Observation, Sistema Satelital para Observación de la Tierra (SSOT), also known as FASat-Charlie, is a Chilean satellite which was launched on December 16, 2011. The objective of the SSOT is to have a satellite system for the observation of Earth based on international cooperation. The project was commissioned by the Ministry of Defense from the European space manufacturer EADS Astrium - based in Toulouse, France - and had an acquisition cost of 72.5 million dollars, according to the contract signed on July 25, 2008. The Soyuz rocket was used to put the satellite into orbit, which was launched in French Guiana from the spaceport of Kourou, currently used by the European Space Agency. SSOT is a Miniaturized satellite built on the Myriade satellite bus by EADS Astrium. It was part of a six-satellite payload along with Pléiades-HR 1, ELISA 1, ELISA 2, ELISA 3 and ELISA 4. Background Prior to FASat-Charlie, Chile had two experiences with m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ELISA (satellite)
ELISA (ELectronic Intelligence by SAtellite) is a suite of four French military satellites launched on 17 December 2011 from Arianespace's Kourou spaceport in French Guiana. It consists of microsatellites ELISA 1 (or ELISA W11, COSPAR ID: 2011-076A), ELISA 2 (or ELISA E12, COSPAR ID: 2011-076D), ELISA 3 (or ELISA W23, COSPAR ID: 2011-076C), and ELISA 4 (or ELISA E24, COSPAR ID: 2011-076B) The entire ELISA suite was launched on a single Soyuz ST-A launch vehicle, along with Pléiades-1 and SSOT. The ELISA programme is a demonstrator meant to pave the way for a planned Signals intelligence constellation called CERES. The ELISA satellites are in a Low Earth orbit a few kilometres from each other to record radar and radio transmissions. Since 2014, they are used as a pre-operational system. The satellites are built around the Myriade microsatellite bus. See also * ESSAIM - another French military SIGINT microsatellite project * CERES Ceres most commonly refers to: * Ceres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TARANIS
In Celtic mythology, Taranis (Proto-Celtic: *''Toranos'', earlier ''*Tonaros''; Latin: Taranus, earlier Tanarus) is the god of thunder, who was worshipped primarily in Gaul, Hispania, Britain, and Ireland, but also in the Rhineland and Danube regions, amongst others. Taranis, along with Esus and Toutatis, was mentioned by the Roman poet Lucan in his epic poem ''Pharsalia'' as a Celtic deity to whom human sacrificial offerings were made. Taranis was associated, as was the Cyclops Brontes ("thunder") in Greek mythology, with the wheel. Many representations of a bearded god with a thunderbolt in one hand and a wheel in the other have been recovered from Gaul, where this deity apparently came to be syncretised with Jupiter. Name and etymology The Proto-Celtic form of the name is reconstructed as *''Toranos'' ('Thunder'), which derives through metathesis (switch of sounds) from an earlier *''Tonaros'', itself from the Proto-Indo-European (PIE) stem for 'thunder', *''(s)tenh₂- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MICROSCOPE (satellite)
A microscope () is a laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. Microscopic means being invisible to the eye unless aided by a microscope. There are many types of microscopes, and they may be grouped in different ways. One way is to describe the method an instrument uses to interact with a sample and produce images, either by sending a beam of light or electrons through a sample in its optical path, by detecting photon emissions from a sample, or by scanning across and a short distance from the surface of a sample using a probe. The most common microscope (and the first to be invented) is the optical microscope, which uses lenses to refract visible light that passed through a thinly sectioned sample to produce an observable image. Other major types of microscopes are the fluorescence microscope, electron microscope (both the transmis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picard (satellite)
PICARD is a satellite dedicated to the simultaneous measurement of the absolute total and spectral solar irradiance, the diameter and solar shape, and to the Sun's interior probing by the helioseismology method. These measurements obtained throughout the mission allow study of their variations as a function of solar activity. It launched, along with the Prisma spacecraft, on 15 June 2010 on a Dnepr launcher from Dombarovskiy Cosmodrome, near Yasny, Russia. The mission, originally planned for two years, ended on 4 April 2014. Objectives The objectives of the PICARD mission are to improve our knowledge of: * the functioning of our star through new observations, * the influence of the solar activity on the climate of the Earth. History The PICARD mission was named after the French astronomer of the 17th century Jean Picard (1620–1682) who achieved the first accurate measurements of the solar diameter. These measurements are especially important as they were made during a p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasol (satellite)
PARASOL (Polarization & Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) was a French-built Earth observing research satellite. It carried an instrument called POLDER which studied the radiative and microphysical properties of clouds and aerosols. PARASOL was launched from the French spaceport in Kourou, French Guiana on December 18, 2004 by an Ariane 5 G+. It flew in formation in the " A Train" constellation with several other satellites (Aqua, CALIPSO, CloudSat and Aura). These satellites had, for the first time ever, combined a full suite of instruments for observing clouds and aerosols, from passive radiometers to active lidar and radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, w ... sounders. On 2 December 2009, PARASOL was man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Essaim (satellite)
Essaim (''swarm'', in French) was a French military reconnaissance microsatellite constellation. Its main purpose was to collect and map signals intelligence around the world. The Direction générale de l'armement (DGA) described it as a "vacuum cleaner for adiowaves". Description Essaim was a constellation of four 120 kg microsatellites (one of which was a spare) in low Earth orbit (LEO). They were demonstration models which were supposed to last three years. They flew separated by a few hundreds of kilometers. Missions were designed by the ''Celar'' (Centre d'électronique de l'armement) in Bruz, near Rennes and were uploaded from CNES in Toulouse to the constellation. Collected data followed the same path in reverse order. Launch The constellation was launched from Kourou, in French Guiana, by an Ariane 5 G+ launch vehicle on 18 December 2004. The flight was shared with Helios 2A and two other auxiliary payloads: Parasol and Nanosat. Individual members of the cons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Demeter (satellite)
DEMETER (Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions) was a French micro-satellite operated by CNES devoted to the investigation of the ionospheric disturbances due to seismic and volcanic activity. It was launched on June 29, 2004, on a quasi Sun-synchronous circular orbit with an inclination of about 98.23° and an altitude of about 710 km. The altitude was changed to about 660 km in December 2005. Due to the specific orbit, DEMETER was always located either shortly before the local noon (10:30 local time) or local midnight (22:30 local time). The satellite performs 14 orbits per day and measures continuously between -65° and +65° of invariant latitude. DEMETER observed an increase in ultra low frequency radio waves in the month before the 2010 Haiti earthquake. During the 2010 eruption of Mount Merapi, DEMETER noted anomalies in the ionosphere. Scientific operations ended December 9, 2010. Scientific Objectives * To study the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wet Mass
In aerospace engineering, mass ratio is a measure of the efficiency of a rocket. It describes how much more massive the vehicle is with propellant than without; that is, the ratio of the rocket's ''wet mass'' (vehicle plus contents plus propellant) to its ''dry mass'' (vehicle plus contents). A more efficient rocket design requires less propellant to achieve a given goal, and would therefore have a lower mass ratio; however, for any given efficiency a higher mass ratio typically permits the vehicle to achieve higher delta-v. The mass ratio is a useful quantity for back-of-the-envelope rocketry calculations: it is an easy number to derive from either \Delta or from rocket and propellant mass, and therefore serves as a handy bridge between the two. It is also a useful for getting an impression of the size of a rocket: while two rockets with mass fractions of, say, 92% and 95% may appear similar, the corresponding mass ratios of 12.5 and 20 clearly indicate that the latter syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Technology 5 On Payload Structure
Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum known as spacetime. The concept of space is considered to be of fundamental importance to an understanding of the physical universe. However, disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework. Debates concerning the nature, essence and the mode of existence of space date back to antiquity; namely, to treatises like the ''Timaeus'' of Plato, or Socrates in his reflections on what the Greeks called ''khôra'' (i.e. "space"), or in the ''Physics'' of Aristotle (Book IV, Delta) in the definition of ''topos'' (i.e. place), or in the later "geometrical conception of place" as "space ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
