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A non-inclined orbit is an orbit coplanar with a plane of reference.The orbital inclination is 0° for prograde orbits, and π (180°) for retrograde ones. [citation needed]If the plane of reference is a massive spheroid body's equatorial plane, these orbits are called equatorial, and the non-inclined orbit is merely a special case of the near-equatorial orbit.
For rockets and space vehicles, propellants usually take up 2/3 or more of their total mass. Large upper-stage rocket engines generally use a cryogenic fuel like liquid hydrogen and liquid oxygen (LOX) as an oxidizer because of the large specific impulse possible, but must carefully consider a problem called "boil off," or the evaporation of the cryogenic propellant.
Ecliptic orbit: A non-inclined orbit with respect to the ecliptic. Equatorial orbit: A non-inclined orbit with respect to the equator. Near equatorial orbit: An orbit whose inclination with respect to the equatorial plane is nearly zero. This orbit allows for rapid revisit times (for a single orbiting spacecraft) of near equatorial ground sites.
The remaining nitrogen is, in part, used as propellant for a nuclear-powered magnetohydrodynamic electromagnetic plasma thruster, which maintains the orbit at about 120 km, or a solar powered thruster (and collection system) for altitudes above 150 km (as stated in the original 1959 JBIS article, p119) compensating for atmospheric drag. [2]
Liquid rocket engines have tankage and pipes to store and transfer propellant, an injector system and one or more combustion chambers with associated nozzles.. Typical liquid propellants have densities roughly similar to water, approximately 0.7 to 1.4 g/cm 3 (0.025 to 0.051 lb/cu in).
Notable single stage to orbit concepts include Skylon, which used the hybrid-cycle SABRE engine that can use oxygen from the atmosphere when it is at low altitude, and then using onboard liquid oxygen after switching to the closed cycle rocket engine at high altitude, the McDonnell Douglas DC-X, the Lockheed Martin X-33 and VentureStar which ...
In this case, non-inclined orbits are called equatorial. [2] For a heliocentric orbit, the ecliptic or invariable plane. In this case, non-inclined orbits are called ecliptic. [2] 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). [3]
The orbit is "distant" in the sense that it passes above the Lagrange points, rather than being near the moon. Considering more and more distant orbits, the synodic period (the period between two moments when the craft passes between the planet and the moon) gets longer and approaches that of the moon going around the planet.