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2-2-1-2 DECLARATION OF THE FIRST MEETING OF EQUATORIAL COUNTRIES(Adopted on December 3,1976) The geostationary orbit is a circular orbit on the Equatorial plane in which the period of sideral revolution of the satellite is equal to the period of sideral rotation of the Earth and the satellite moves in the same direction of the Earth's rotation. Equatorial countries declare that the geostationary synchronous orbit is a physical fact linked to the reality of our planet because its existence depends exclusively on its relation to gravitational phenomena generated by the earth, and that is why it must not be considered part of the outer space. The geostationary orbit is a scarce natural resource, whose importance and value increase rapidly together with the development of space technology and with the growing need for communication; therefore, the Equatorial countries meeting in Bogota have decided to proclaim and defend on behalf of their peoples, the existence of their sovereignty over this natural resource. www.jaxa.jp /library/space_law/chapter_2/2-2-1-2_e.html   (1177 words)

satellite, artificial - HighBeam Encyclopedia If placed in an orbit high enough to escape the frictional effects of the earth's atmosphere, the motion of the satellite is controlled by the same laws of celestial mechanics that govern the motions of natural satellites, and it will remain in orbit indefinitely. Unless corrections are made, orbits are usually elliptical; perigee is the point on the orbit closest to the earth, and apogee is the point farthest from the earth. The combination of the small number of Transit satellites and their polar orbits meant there were some areas of the globe that were not continuously covered—as a result, the users had to wait until a satellite was properly positioned before they could obtain navigational information. www.encyclopedia.com /doc/1E1-satelart.html   (1735 words)

Satellite orbiting toward west in the equatorial plane and meteorological satellite system using the satellite - Patent ... Further, the polar orbit meteorological satellites are in sun synchronous orbits having altitudes of 833 to 870 km and inclination angles of 98.86 to 98.70 degrees, being deployed as one in each of the two orbits having their orbital planes perpendicular to each other. Since the orbital radius of the satellite according to the present invention is about one half that of the geostationary orbit, the fuel for maintaining the inclination angle of the orbit which is required in proportion to the tidal force becomes about one half that in the case of a geostationary meteorological satellite. The fact that a useful orbit must be in the equatorial plane can be seen from both the feasibility of using an antenna of such simple construction at a receiving station and the need for preventing a change in the configuration from one to another of the images as shown in FIG. www.freepatentsonline.com /6082677.html   (4378 words)

RS:Principles: Sensors The lowest satellites orbit the earth with a period of approximately 87 minutes per orbit (if a satellite were placed any lower in the orbit the atmosphere would interfere so much that it could not maintain its orbit). Inclination of a satellite orbit describes the tilt of the orbit plane with respect to the equatorial plane. An orbit with an inclination angle of 90º would orbit the Earth crossing the North and South Poles in a plane that is perpendicular to the equatorial plane. chesapeake.towson.edu /data/orbits3.asp   (616 words)

Introduction to satellite communications Orbits generally are described according to the physical shape of the orbit and the angle of inclination of the plane of the orbit. A satellite orbiting in an inclined orbit with an angle of inclination of 90 degrees or near 90 degrees is in a POLAR ORBIT. If the orbit is lower than 19,300 nautical miles, the period of orbit of the satellite is less than the period of orbit of the earth. www.tpub.com /neets/book17/76.htm   (1695 words)

Orbits The orbit chosen for a satellite is a compromise between the mission requirements, the capabilities of the rocket used to launch the satellite and orbital mechanics. Additionally the orbit is resonant with the rotation period of the earth, meaning that the satellite passes over the same point on the earth at the same time of day at regular intervals (which may be daily or every 2 or more days depending on the resonance). A geostationary orbit is a special case of the geosynchronous orbit where inclination = 0 and the period is equal to the rotation period of the earth (approx 1436 minutes), corresponding to a circular orbit of approx. zebu.uoregon.edu /~js/space/lectures/lec06.html   (3325 words)

orbit In an elliptical orbit, the speed varies and is greatest at perigee (minimum altitude) and least at apogee (maximum altitude). As long as the orbit of an object keeps it in the vacuum of space, the object will continue to orbit without propulsive power because there is no frictional force to slow it down. An open orbit is one in which a spacecraft does not follow a closed circuit around a gravitating body but simply has its path bent into the shape of a parabola or hyperbola. www.daviddarling.info /encyclopedia/O/orbit.html   (371 words)

Artificial Satellite - MSN Encarta The lifetime of a satellite depends on its orbit, the satellite’s orientation in its orbit, and the size, shape, and weight of the satellite. Most orbits are circular, but some satellites use elliptical orbits—that is, orbits in which the satellite’s distance from Earth is not constant. Satellites in geostationary equatorial orbit (GEO) orbit Earth around the equator at a very specific altitude that allows them to complete one orbit in the same amount of time that it takes Earth to rotate once. encarta.msn.com /encyclopedia_761551926_4/Artificial_Satellite.html   (701 words)

Spartanburg SC | GoUpstate.com | Spartanburg Herald-Journal   (Site not responding. Last check: 2007-11-04) Typical Sun-synchronous orbits are about 600–800 km in altitude, with periods in the 96–100 minute range, and inclinations of around 98° (ie slightly retrograde compared to the direction of Earth's rotation: 0° represents an equatorial orbit and 90° represents a polar orbit). Variations on this type of orbit are possible; a satellite could have a highly eccentric sun-synchronous orbit, in which case the "fixed solar time of passage" only holds for a chosen point of the orbit (typically the perigee). For a sun-synchronous orbit, the precession is retrograde (that is, opposite to the Earth's spin direction) in order to slow the apparent movement of the satellite around the Earth to match the Earth's rotation. www.goupstate.com /apps/pbcs.dll/section?category=NEWS&template=wiki&text=Sun-synchronous_orbit   (724 words)

Footprints by Dish Size - Definition of Geostationary (Geosynchronous), Polar, LEO, HEO, MEO, Sun Synchronous Orbits, ... More technically, a geostationary orbit is a circular prograde orbit in the equatorial plane with an orbital period equal to that of the earth; this is achieved with an orbital radius of 6.6107 (equatorial) earth radii, or an orbital height of 35786 km. If the orbit is in the equatorial plane, and if rotation is in the same direction as the Earth, (rotating at the same angular velocity as the Earth) and it overflies the same point on the globe permanently then the satellite is termed geostationary. Radarsat is in orbit 798 kilometres above the Earth, at an angle of inclination of 98.6 degrees to the equator as it circles the globe from north pole to south pole. www.geo-orbit.org /sizepgs/geodef.html   (6827 words)

Satellite Observing: Orbital Elements The orbit ellipse lies in a plane, and this plane forms an angle with the plane of the equator. Since the orbit is fixed relative to the stars and not to the surface of the Earth, the astronomical coordinate system of right ascension and declination is used to measure the position of the ascending node. Right ascension is an angle measured in the equatorial plane from a fixed point in space, called the point of Ares (which is also the point of the vernal equinox, where there Sun crosses the equator in the spring). www.znark.com /sat/elements.html   (936 words)

Applied Orbit Perturbation and Maintenance The square of an orbiting body's revolutionary period is proportional to the cube of the satellite's mean distance from the central body. Orbit perturbations to be discussed in the later chapters of this book will be in terms of the deviations from those six classic elements. A geosynchronous or geostationary drift orbit is a circular orbit with a mean altitude either higher or lower than the stationary altitude required for a newly launched satellite to move to its desired longitude, usually at a rate of 3 deg/day, equivalent to an altitude of 234 km above or below GEO altitude. www.aero.org /publications/chao/index.html   (1357 words)

Launching and Retrieving Satellites When they are launched into polar orbits, which means to move in a direction from the North Pole to the South Pole, their booster thrust must provide the whole orbital velocity. In addition, as in an equatorial orbit, the movement of direction from east to west or vice versa. Apogee is the point in the orbit of the moon or of a artificial satellite where it is farthest from the earth. www.smgaels.org /physics/97/MATTD~1.HTM   (758 words)

CelesTrak: "Basics of the Geostationary Orbit" While each satellite will complete its orbit in the same time it takes the earth to rotate once, it should be obvious that the geosynchronous satellite will move north and south of the equator during its orbit while the geostationary satellite will not. Orbits with non-zero eccentricity (i.e., elliptical rather than circular orbits) will result in drifts east and west as the satellite goes faster or slower at various points in its orbit. Since the geostationary orbital plane is not coincident with the plane of the earth's orbit (the ecliptic) or that of the moon's orbit, the gravitational attraction of the sun and the moon act to pull the geostationary satellites out of their equatorial orbit, gradually increasing each satellite's orbital inclination. celestrak.com /columns/v04n07   (1553 words)

Orbit definitions (Henry Spencer)   (Site not responding. Last check: 2007-11-04) Clarke orbit Some people prefer this to "geostationary", given that Arthur C. Clarke was the first person to realize how useful this orbit would be for comsats. GTO Geostationary Transfer Orbit, an orbit at modest inclination with perigee at LEO and apogee at Clarke orbit. The Earth's equatorial bulge normally causes the position of apogee&perigee to rotate in the plane of an elliptical orbit, but at the particular inclination of the Molniya orbits, this effect is zero and the apogee stays where it's put. yarchive.net /space/orbits/orbit_definitions.html   (605 words)

Moonport, CH1-2   (Site not responding. Last check: 2007-11-04) In higher orbits, the penalty was less severe but still involved at least a 20% loss of payload. There were also significant disadvantages to an equatorial launch base: higher construction costs (about 100% greater), logistics problems, and the hazards of setting up an American base on foreign soil. The only definite plans for equatorial orbits were in connection with communications and meteorological satellites operating at 35,000 kilometers. www.hq.nasa.gov /pao/History/SP-4204/ch1-2.html   (545 words)

RS:Principles: Intro to Satellites and Orbits A geostationary satellite orbits the Earth in an equatorial orbit at an altitude where its period is equal to that of the Earth's rotation (24 hours). A geostationary orbit is usually circular with an inclination of 0º. The period of a HEO satellite is approximately 12 hours and the shape of the orbit is highly elliptical. chesapeake.towson.edu /data/orbits4.asp   (403 words)

Satellite Orbits A geostationary (GEO=geosynchronous) orbit is one in which the satellite is always in the same position with respect to the rotating Earth. By orbiting at the same rate, in the same direction as Earth, the satellite appears stationary (synchronous with respect to the rotation of the Earth). Orbiting at an altitude of 700 to 800 km, these satellites cover best the parts of the world most difficult to cover in situ (on site). asd-www.larc.nasa.gov /SCOOL/orbits.html   (496 words)

Lunar orbit (Henry Spencer) Newsgroups: sci.space.history From: Henry Spencer Subject: Re: Apollo polar orbit question Date: Mon, 1 Dec 1997 00:51:08 GMT In article <65sru2$fgt@omnifest.uwm.edu>, Chris Roth wrote: >Suppose one of the final Apollo flights was a nonlanding >mission. To a crude first approximation, an economy trajectory to the Moon is an elliptical orbit with its perigee as low as possible and its apogee at roughly lunar distance. It is marginally possible that a carefully-chosen and quite low orbit could exploit lunar mascons to do the same trick, given a complete and detailed understanding of the lunar gravitational field (which we don't have yet), but I wouldn't bet money on it. yarchive.net /space/orbits/lunar_orbit.html   (1805 words)

[No title] He explained that if you look at the energy required to get into earth orbit, a function of the earth's mass and the gravitational constant, and compare it with the energy of chemical bonds which we break and remake to create rocket propulsion, it turns out to be just barely possible to get into orbit. The most popular single orbit is geosynchronous -- the orbit with a period identical to that of earth's rotation and with a plane including earth's equator. This is not an equatorial orbit, and your satellite will never appear to be stationary over one spot. www.mindspring.com /~rfleeter/choosingsite.htm   (1501 words)

ESA - Space Science - Types of orbit All four classes of orbit are known as ‘conic sections’ because slicing a cylindrical cone in a different way can make each of their shapes. Closed orbits are achieved by cutting a cone from one side to another at different angles. In a polar orbit, the spacecraft can be made to follow any line of longitude, since these always lead from one pole to the other, and then any line of longitude leads back again on the other side of the Earth. www.esa.int /esaSC/SEMU4QS1VED_index_0.html   (522 words)

Hohmann Transfer To change from a lower orbit (A) to a higher orbit (C), an engine is first fired in the opposite direction from the direction the vehicle is traveling. So, if the satellite is in an orbit inclined 28.5 degrees to the equator the firing must occur at one of two points during each orbit revolution where the spacecraft is directly over the equator. If you are in an inclined orbit and you want to make it equatorial, you must produce a change in the velocity and add it to the original velocity vector, which will generate the desired velocity vector. liftoff.msfc.nasa.gov /academy/rocket_sci/satellites/hohmann.html   (852 words)

Basics of Space Flight Section I. The Environment of Space As an orbiting body crosses the ecliptic plane going north, the node is referred to as the ascending node; going south, it is the descending node. To attain geosynchronous (and also geostationary) Earth orbits, a spacecraft is first launched into an elliptical orbit with an apoapsis altitude in the neighborhood of 37,000 km. The result is called a walking orbit or a precessing orbit, since the orbital plane moves slowly with respect to fixed inertial space. www2.jpl.nasa.gov /basics/bsf5-1.html   (1166 words)

SSHP - Orbital terms A polar orbit is inclined at about 90 degrees to the equatorial plane, covering both poles. A Sun-synchronous or helio-synchronous orbit is a special form of Low Earth polar Orbit, where the angle between the orbital plane and Sun remains constant. If a satellite is placed in a circular prograde equatorial orbit, and the height is chosen such that the orbital period is equal to that of the Earth, then the satellite will appear fixed above the Earth's surface. centaur.sstl.co.uk /SSHP/orbterm.html   (373 words)

Satellite system using equatorial and polar orbit relays - Patent 5678175 While a variety of numbers of orbit planes and satellites may be employed to implement the present invention, the reader should understand that the invention embraces any configuration that does not utilize geo-stationary spacecraft flying in orbits at an altitude of approximately 23,000 miles, except for using geo-stationary spacecraft as a communications link. These Equatorial relay stations 34 are capable of communicating with the satellites 12 in the Equatorial orbit via uplinks 35a and downlinks 35b. In this embodiment 64a, since satellites 12 in sectors of orbits 210 on the same side of the Earth E will be transmitting on the same frequencies without interference from other satellites 12, it is possible to reduce the bandwidth of the TSD downlink signal spectrum to one-fourth of that used in some other embodiments. www.freepatentsonline.com /5678175.html   (14348 words)

Investigation of the equatorial LEO orbit for small satellite applications Artificial satellites launched into circular orbit around the earth for communications, scientific research, remote sensing, surveillance, meteorology, navigation and other purposes can be classified as GEO (Geostationary Earth Orbit), MEO (Medium Earth Orbit) or LEO (Low Earth Orbit) system according to the heights of their orbits. MEO orbits have greater heights than LEO orbits, usually between 5,000 and 15,000 km. For equatorial LEO orbit, the geometry is shown in Figure 7 where d, the inter-satellite distance, and y, the path clearance at the equator, are given by: www.ee.surrey.ac.uk /SSC/CSER/UOSAT/IJSSE/issue1/seumahu/seumahu.html   (2491 words)

Space Future - Benefits of International Cooperation in a Low Equatorial Orbit SPS Pilot Plant Demonstrator Project An equatorial orbit was judged the best candidate for a cost-effective pilot-plant demonstrator in low Earth orbit which is to be used to actually supply power to consumers, since it overflies all the same places on every orbit. Such a project in equatorial orbit would provide a unique requirement for crewed flights from Kourou, for which there is no substitute. As discussed above, operation of a 10 MW pilot plant in low equatorial orbit is on the critical path to evaluating the potential of space-based solar power systems to supply environmentally clean electric power to the Earth. www.spacefuture.com /archive/benefits_of_international_cooperation_in_a_low_equatorial_orbit_sps_pilot_plant_demonstrator_project.shtml   (3292 words)

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