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  • Earth
  • Fortunately, when the space station was designed, planners recognized that having a platform in low Earth orbit (LEO), which is about half the altitude of most Earth remote sensing satellites, provided researchers the opportunity to do something unique. (nasa.gov)
  • That means that instead of passing over at the same time every day, which is typical of an Earth remote sensing satellite, the space station actually has a precessing orbit and does not go over the poles. (nasa.gov)
  • The precessing orbit of the space station laid out over a map of the Earth. (nasa.gov)
  • This review will consider the impact of true and simulated microgravity and other characteristics of the space flight environment on bacterial cell behavior in relation to the potential for serious infections that may appear during missions to astronomical objects beyond low Earth orbit. (dovepress.com)
  • Scientific research on the International Space Station is a collection of experiments that require one or more of the unusual conditions present in low Earth orbit. (wikipedia.org)
  • Kepler
  • The basis for the modern understanding of orbits was first formulated by Johannes Kepler whose results are summarised in his three laws of planetary motion. (wikipedia.org)
  • Second, he found that the orbital speed of each planet is not constant, as had previously been thought, but rather that the speed depends on the planet's distance from the Sun. Third, Kepler found a universal relationship between the orbital properties of all the planets orbiting the Sun. For the planets, the cubes of their distances from the Sun are proportional to the squares of their orbital periods. (wikipedia.org)
  • Idealised orbits meeting these rules are known as Kepler orbits. (wikipedia.org)
  • For this case the model is simplified to a Kepler orbit. (wikipedia.org)
  • barycenter
  • A heliocentric orbit (also called circumsolar orbit ) is an orbit around the barycenter of the Solar System , which is usually located within or very near the surface of the Sun . All planets , comets , and asteroids in the Solar System, and the Sun itself are in such orbits, as are many artificial probes and pieces of debris . (wikipedia.org)
  • A synchronous orbit has a period equal to the rotational period of the body which contains the barycenter of the orbit. (wikipedia.org)
  • trajectories
  • In relativity theory, orbits follow geodesic trajectories which are usually approximated very well by the Newtonian predictions (except where there are very strong gravity fields and very high speeds) but the differences are measurable. (wikipedia.org)
  • 2000
  • After winning the 2000 Guineas win Ayrshire started as the 5/6 favourite for The Derby and Orbit was second favourite at 11/2. (wikipedia.org)
  • lunar orbit
  • Not to be confused with Lunar orbit (the orbit of an object around the Moon). (wikipedia.org)
  • The non-circular form of the lunar orbit causes variations in the Moon's angular speed and apparent size as it moves towards and away from an observer on Earth. (wikipedia.org)
  • China's lunar orbiter Chang'e 2 left lunar orbit on June 8, 2011 and was placed in a Lissajous orbit at Earth-Sun L2 until mid-2012 prior to leaving Earth orbit entirely to fly by the asteroid 4179 Toutatis. (wikipedia.org)
  • apogee
  • The Moon's major axis - the longest diameter of the orbit, joining its nearest and farthest points, the perigee and apogee , respectively - makes one complete revolution every 8.85 Earth years, or 3,232.6054 days, as it rotates slowly in the same direction as the Moon itself (direct motion). (wikipedia.org)
  • A satellite placed in this orbit spends most of its time over a chosen area of the Earth, a phenomenon known as apogee dwell. (wikipedia.org)
  • These orbits remain over their desired high-latitude regions for long periods of time due to their slow movement at apogee. (wikipedia.org)
  • An argument of perigee of 270° places apogee at the northernmost point of the orbit. (wikipedia.org)
  • In both cases, the satellite owner uses the propulsion built into the satellite to reduce the apogee and circularize the orbit to a geostationary orbit. (wikipedia.org)
  • Hohmann
  • Compromise orbits, faster but needing more energy than true Hohmann orbits, have been used by interplanetary probes launched since the 1960s. (britannica.com)
  • Solar System
  • The moons of planets in the Solar System, by contrast, are not in heliocentric orbits, as they orbit their respective planet (although the Moon has a convex orbit around the Sun). (wikipedia.org)
  • Last summer, I wrote a piece on the search for small solar system objects that might, theoretically, circle the Sun inside Mercury's orbit. (slate.com)
  • First, he found that the orbits of the planets in our solar system are elliptical, not circular (or epicyclic), as had previously been believed, and that the Sun is not located at the center of the orbits, but rather at one focus. (wikipedia.org)
  • prograde
  • The Moon orbits Earth in the prograde direction and completes one revolution relative to the stars in about 27.32 days (a sidereal month ) and one revolution relative to the Sun in about 29.53 days (a synodic month ). (wikipedia.org)
  • typically
  • In practice, Keplerian orbits are typically only useful for first-order approximations, special cases, or as the base model for a perturbed orbit. (wikipedia.org)
  • Orbit models are typically propagated in time and space using special perturbation methods. (wikipedia.org)
  • polar
  • Play media A polar orbit is one in which a satellite passes above or nearly above both poles of the body being orbited (usually a planet such as the Earth, but possibly another body such as the Moon or Sun) on each revolution. (wikipedia.org)
  • 1980
  • Royal Orbit (April 25, 1956 - c. 1980) was an American Thoroughbred racehorse best known as the winner of the Preakness Stakes, the second leg of the U.S. Triple Crown races. (wikipedia.org)
  • In 1980 Orbit teamed up with Laurie Mayer and Grant Gilbert to form the electronic/synth group Torch Song. (wikipedia.org)
  • Earth
  • Calculated for circular orbit of 200 km it is 7.79 km/s and for 1500 km it is 7.12 km/s. The delta-v needed to achieve low Earth orbit starts around 9.4 km/s. (wikipedia.org)
  • Objects in LEO orbit Earth between the denser part of the atmosphere and below the inner Van Allen radiation belt . (wikipedia.org)
  • Higher orbits include medium Earth orbit (MEO), sometimes called intermediate circular orbit (ICO), and further above, geostationary orbit (GEO). (wikipedia.org)
  • A low Earth orbit is simplest and cheapest for satellite placement. (wikipedia.org)
  • Essentially a linked group of short stories, it recounts the colonisation of the planet Rustum, a fictional terrestrial world orbiting Epsilon Eridani, by a group of refugees from an authoritarian planet Earth bearing some resemblance to the historical Pilgrim Fathers. (wikipedia.org)
  • Although Anderson had no way of knowing this at the time of writing, a planet is now known to orbit around Epsilon Eridani, a star only 10.5 light years from earth. (wikipedia.org)
  • Several missions have used Lissajous orbits: ACE at Sun-Earth L1, SOHO at Sun-Earth L1, DSCOVR at Sun-Earth L1, WMAP at Sun-Earth L2, and also the Genesis mission collecting solar particles at L1. (wikipedia.org)
  • On 14 May 2009, the European Space Agency (ESA) launched into space the Herschel and Planck observatories, both of which use Lissajous orbits at Sun-Earth L2. (wikipedia.org)
  • ESA's current Gaia mission also uses a Lissajous orbit at Sun-Earth L2. (wikipedia.org)
  • In the case of an inclined geosynchronous orbit, although the satellite remains geosynchronous (that is, completing one orbit around the earth every 24 hours), it is no longer geostationary. (wikipedia.org)
  • One public policy proposal to deal with growing space debris is a "one-up/one-down" launch license policy for Earth orbits. (wikipedia.org)
  • To keep the same local time on a given pass, the time period of the orbit must be kept as short as possible, this is achieved by keeping the orbit lower to the Earth. (wikipedia.org)
  • To retain the Sun-synchronous orbit as the Earth revolves around the Sun during the year, the orbit of the satellite must precess at the same rate, which is not possible if the satellite were to pass directly over the pole. (wikipedia.org)
  • 1998
  • In 1998 the company established Orbit Bexley Housing Association to take on the management of the 4,500 transferred from the London Borough of Bexley, under a process known as large scale voluntary transfer (LSVT). (wikipedia.org)
  • contrast
  • In contrast, Lissajous orbits include components in this plane and perpendicular to it, and follow a Lissajous curve. (wikipedia.org)
  • periodic
  • Halo orbits also include components perpendicular to the plane, but they are periodic, while Lissajous orbits are not. (wikipedia.org)
  • Homoclinic orbits and homoclinic points are defined in the same way for iterated functions, as the intersection of the stable set and unstable set of some fixed point or periodic point of the system. (wikipedia.org)
  • A heteroclinic orbit is then the joining of two distinct periodic orbits. (wikipedia.org)
  • Thus, a heteroclinic orbit can be understood as the transition from one periodic orbit to another. (wikipedia.org)
  • precession
  • Apsidal precession -the Moon's orbit rotates once every 8.85 years. (wikipedia.org)
  • This orbital precession is also called apsidal precession and is the rotation of the Moon's orbit within the orbital plane, i.e. the axes of the ellipse change direction. (wikipedia.org)
  • an angle of about 8 degrees from the pole produces the desired precession in a 100-minute orbit. (wikipedia.org)
  • 1959
  • In his only out-of-the-money finish in twenty career races, Royal Orbit ran fourth to winner Tomy Lee in the 1959 Kentucky Derby under jockey William Harmatz. (wikipedia.org)
  • Retired at the end of the 1959 racing season, Royal Orbit stood in Kentucky and at the Maryland branch of E.P. Taylor's Windfields Farm. (wikipedia.org)
  • simplest
  • In its simplest form, an orbit model can be created by assuming that only two bodies are involved, both behave as spherical point-masses, and that no other forces act on the bodies. (wikipedia.org)
  • operate
  • This orbit, referred to as "VLEO", requires the use of novel technologies for orbit raising because they operate in orbits that would ordinarily decay too soon to be economically useful. (wikipedia.org)
  • equilibrium
  • In practice, any orbits around Lagrangian points L1, L2, or L3 are dynamically unstable, meaning small departures from equilibrium grow over time. (wikipedia.org)
  • planetary
  • The study of orbital motion and mathematical modeling of orbits began with the first attempts to predict planetary motions in the sky, although in ancient times the causes remained a mystery. (wikipedia.org)
  • decay
  • However, very low orbits of a few hundred kilometers rapidly decay due to drag from the atmosphere. (wikipedia.org)
  • artificial
  • Where one body is much more massive than the other (as is the case of an artificial satellite orbiting a planet), it is a convenient approximation to take the center of mass as coinciding with the center of the more massive body. (wikipedia.org)
  • Shape
  • GOCE orbited at about 255 km and had an aerodynamic shape and ion thrusters to reduce and compensate for atmospheric drag. (wikipedia.org)
  • bodies
  • Newton showed that, for a pair of bodies, the orbits' sizes are in inverse proportion to their masses, and that those bodies orbit their common center of mass. (wikipedia.org)
  • Lyapunov orbits around a Lagrangian point are curved paths that lie entirely in the plane of the two primary bodies. (wikipedia.org)