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Geosynchronous Transfer Orbit
A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellites that are destined for geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into a GTO as an intermediate step for reaching their final orbit. A GTO is highly elliptic. Its perigee (closest point to Earth) is typically as high as low Earth orbit (LEO), while its apogee (furthest point from Earth) is as high as geostationary (or equally, a geosynchronous) orbit. That makes it a Hohmann transfer orbit between LEO and GSO. Larson, Wiley J. and James R. Wertz, eds. Space Mission Design and Analysis, 2nd Edition. Published jointly by Microcosm, Inc. (Torrance, CA) and Kluwer Academic Publishers (Dordrecht/Boston/London). 1991. While some GEO satellites are launched direct to that orbit, often the launch vehicle lacks the power to put both the rocket and the satellite into that orbit. Instead extra fuel is added to the satellite, the launch vehicle la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EchoStar XVII
EchoStar XVII or EchoStar 17, also known as Jupiter 1, is an American geostationary high throughput communications satellite which is operated by Hughes Network Systems, a subsidiary of EchoStar. It is positioned in geostationary orbit at a longitude of 107.1° West, from where it is used for satellite internet access over HughesNet. EchoStar XVII was built by Space Systems/Loral, and is based on the LS-1300 satellite bus. It measures by by , with solar arrays which were deployed after launch, and generates a minimum of 16.1 kilowatts of power. The spacecraft had a mass at liftoff of , and is expected to operate for fifteen years. It carries sixty (NATO K band) transponders which is used to cover North America. EchoStar XVII was launched by Arianespace, using an Ariane 5ECA carrier rocket flying from ELA-3 at Kourou. The spacecraft was launched at 21:36 UTC on 5 July 2012. The MSG-3 weather satellite was launched aboard the same rocket, mounted below EchoStar XVII, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supersynchronous Orbit
A supersynchronous orbit is either an orbit with a period greater than that of a synchronous orbit, or just an orbit whose apoapsis (apogee in the case of the Earth) is higher than that of a synchronous orbit. A synchronous orbit has a period equal to the rotational period of the body which contains the barycenter of the orbit. Geocentric supersynchronous orbits One particular supersynchronous orbital regime of significant economic value to Earth commerce is a band of near-circular Geocentric orbits beyond the geosynchronous belt—with perigee altitude above , approximately above synchronous altitude —called the geo graveyard belt. The geo graveyard belt orbital regime is valuable as a storage and disposal location for derelict satellite space debris after their useful economic life is completed as geosynchronous communication satellites. Artificial satellites are left in space because the economic cost of removing the debris would be high, and current public polic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbekistan to the south, and Turkmenistan to the southwest, with a coastline along the Caspian Sea. Its capital is Astana, known as Nur-Sultan from 2019 to 2022. Almaty, Kazakhstan's largest city, was the country's capital until 1997. Kazakhstan is the world's largest landlocked country, the largest and northernmost Muslim-majority country by land area, and the ninth-largest country in the world. It has a population of 19 million people, and one of the lowest population densities in the world, at fewer than 6 people per square kilometre (15 people per square mile). The country dominates Central Asia economically and politically, generating 60 percent of the region's GDP, primarily through its oil and gas industry; it also has vast minera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baikonur Cosmodrome
''Baiqoñyr ğaryş ailağy'' rus, Космодром Байконур''Kosmodrom Baykonur'' , image = Baikonur Cosmodrome Soyuz launch pad.jpg , caption = The Baikonur Cosmodrome's "Gagarin's Start" Soyuz launch pad prior to the rollout of Soyuz TMA-13, 10 October 2008. , LID = GC0015 , type = Spaceport , owner-oper = Roscosmos Russian Aerospace Forces , location = Kazakhstan (leased to Russia) , opened = , built = , timezone = UTC+06:00 , utc = +06:00 , elevation-m = 90 , metric-elev = y , coordinates = , website = , image_map = , image_mapsize = , image_map_alt = , image_map_caption = , pushpin_map = Kazakhstan#Russia#Soviet Union , pushp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Russia
Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eighth of Earth's inhabitable landmass. Russia extends across eleven time zones and shares land boundaries with fourteen countries, more than any other country but China. It is the world's ninth-most populous country and Europe's most populous country, with a population of 146 million people. The country's capital and largest city is Moscow, the largest city entirely within Europe. Saint Petersburg is Russia's cultural centre and second-largest city. Other major urban areas include Novosibirsk, Yekaterinburg, Nizhny Novgorod, and Kazan. The East Slavs emerged as a recognisable group in Europe between the 3rd and 8th centuries CE. Kievan Rus' arose as a state in the 9th century, and in 988, it adopted Orthodox Christianity from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apogee Kick
An apogee kick motor (AKM) is a rocket motor that is regularly employed on artificial satellites to provide the final impulse to change the trajectory from the transfer orbit into its final (most commonly circular) orbit. For a satellite launched from the Earth, the rocket firing is done at the highest point of the transfer orbit, known as the apogee. An apogee kick motor is used, for example, for satellites launched into a geostationary orbit. As the vast majority of geostationary satellite launches are carried out from spaceports at a significant distance away from Earth's equator, the carrier rocket often only launches the satellite into an orbit with a non-zero inclination approximately equal to the latitude of the launch site. This orbit is commonly known as a "geostationary transfer orbit" or a "geosynchronous transfer orbit". The satellite must then provide thrust to bring forth the needed delta v to reach a geostationary orbit. This is typically done with a fixed on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semi-major Axis
In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the two most widely separated points of the perimeter. The semi-major axis (major semiaxis) is the longest semidiameter or one half of the major axis, and thus runs from the centre, through a focus, and to the perimeter. The semi-minor axis (minor semiaxis) of an ellipse or hyperbola is a line segment that is at right angles with the semi-major axis and has one end at the center of the conic section. For the special case of a circle, the lengths of the semi-axes are both equal to the radius of the circle. The length of the semi-major axis of an ellipse is related to the semi-minor axis's length through the eccentricity and the semi-latus rectum \ell, as follows: The semi-major axis of a hyperbola is, depending on the convention, plus or minus one half of the distance between the two branches. Thus it is the distance from the cente ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Mechanics For Engineering Students
''Orbital Mechanics for Engineering Students'' is an aerospace engineering textbook by Howard D. Curtis, in its fourth edition . The book provides an introduction to orbital mechanics, while assuming an undergraduate-level background in physics, rigid body dynamics, differential equations, and linear algebra. Topics covered by the text include a review of kinematics and Newtonian dynamics, the two-body problem, Kepler's laws of planetary motion, orbit determination, orbital maneuvers, relative motion and rendezvous, and interplanetary trajectories. The text focuses primarily on orbital mechanics, but also includes material on rigid body dynamics, rocket vehicle dynamics, and attitude control. Control theory and spacecraft control systems are less thoroughly covered. The textbook includes exercises at the end of each chapter, and supplemental material is available online, including MATLAB MATLAB (an abbreviation of "MATrix LABoratory") is a proprietary multi-paradigm pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Node
An orbital node is either of the two points where an orbit intersects a plane of reference to which it is inclined. A non-inclined orbit, which is contained in the reference plane, has no nodes. Planes of reference Common planes of reference include the following: * For a geocentric orbit, Earth's equatorial plane. In this case, non-inclined orbits are called ''equatorial''. * For a heliocentric orbit, the ecliptic or invariable plane. In this case, non-inclined orbits are called ''ecliptic''. * For an orbit outside the Solar System, the plane through the primary perpendicular to a line through the observer and the primary (called the ''plane of the sky''). Node distinction If a reference direction from one side of the plane of reference to the other is defined, the two nodes can be distinguished. For geocentric and heliocentric orbits, the ascending node (or north node) is where the orbiting object moves north through the plane of reference, and the descending nod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Eccentricity
In astrodynamics, the orbital eccentricity of an astronomical object is a dimensionless parameter that determines the amount by which its orbit around another body deviates from a perfect circle. A value of 0 is a circular orbit, values between 0 and 1 form an elliptic orbit, 1 is a parabolic escape orbit (or capture orbit), and greater than 1 is a hyperbola. The term derives its name from the parameters of conic sections, as every Kepler orbit is a conic section. It is normally used for the isolated two-body problem, but extensions exist for objects following a rosette orbit through the Galaxy. Definition In a two-body problem with inverse-square-law force, every orbit is a Kepler orbit. The eccentricity of this Kepler orbit is a non-negative number that defines its shape. The eccentricity may take the following values: * circular orbit: ''e'' = 0 * elliptic orbit: 0 < ''e'' < 1 * [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azimuth
An azimuth (; from ar, اَلسُّمُوت, as-sumūt, the directions) is an angular measurement in a spherical coordinate system. More specifically, it is the horizontal angle from a cardinal direction, most commonly north. Mathematically, the relative position vector from an observer ( origin) to a point of interest is projected perpendicularly onto a reference plane (the horizontal plane); the angle between the projected vector and a reference vector on the reference plane is called the azimuth. When used as a celestial coordinate, the azimuth is the horizontal direction of a star or other astronomical object in the sky. The star is the point of interest, the reference plane is the local area (e.g. a circular area with a 5 km radius at sea level) around an observer on Earth's surface, and the reference vector points to true north. The azimuth is the angle between the north vector and the star's vector on the horizontal plane. Azimuth is usually measured i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latitude
In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pole, with 0° at the Equator. Lines of constant latitude, or ''parallels'', run east–west as circles parallel to the equator. Latitude and ''longitude'' are used together as a coordinate pair to specify a location on the surface of the Earth. On its own, the term "latitude" normally refers to the ''geodetic latitude'' as defined below. Briefly, the geodetic latitude of a point is the angle formed between the vector perpendicular (or ''normal'') to the ellipsoidal surface from the point, and the plane of the equator. Background Two levels of abstraction are employed in the definitions of latitude and longitude. In the first step the physical surface is modeled by the geoid, a surface which approximates the mean sea level over the ocea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
