fixed orbit
61Muscle — is the tissue of the body which primarily functions as a source of power. There are three types of muscle in the body. Muscle which is responsible for moving extremities and external areas of the body is called "skeletal muscle." Heart… …
62Moon — This article is about Earth s Moon. For moons in general, see Natural satellite. For other uses, see Moon (disambiguation) …
63Spacecraft propulsion — A remote camera captures a close up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Spacecraft propulsion is any method used to accelerate spacecraft and artificial… …
64Precession (astronomy) — In astronomy, precession refers to the movement of the rotational axis of a body, such as a planet, with respect to inertial space. In particular, it refers to the precession of the Earth s rotational axis, also called the precession of the… …
65Sundial — A sundial is a device that measures time by the position of the Sun. In common designs such as the horizontal sundial, the sun casts a shadow from its style (a thin rod or a sharp, straight edge) onto a flat surface marked with lines indicating… …
66Space Shuttle — STS redirects here. For other uses, see STS (disambiguation). This article is about the NASA Space Transportation System vehicle. For the associated NASA STS program, see Space Shuttle program. For other shuttles and aerospace vehicles, see… …
67Orbital station-keeping — In astrodynamics orbital station keeping is a term used to describe the orbital maneuvers made by thruster burns that are needed to keep a spacecraft in a particular assigned orbit. For many Earth satellites the effects of the non Keplerian… …
68calendar — calendrical /keuh len dri keuhl/, calendric, calendarial /kal euhn dair ee euhl/, calendarian, calendaric, adj. /kal euhn deuhr/, n. 1. a table or register with the days of each month and week in a year: He marked the date on his calendar. 2. any …
69aerospace industry — Introduction assemblage of manufacturing concerns that deal with vehicular flight within and beyond the Earth s atmosphere. (The term aerospace is derived from the words aeronautics and spaceflight.) The aerospace industry is engaged in the …
70Mandelbrot set — Initial image of a Mandelbrot set zoom sequence with a continuously coloured environment …
