transfer between circular orbits
71Orbital 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… …
72Uranus — /yoor euh neuhs, yoo ray /, n. 1. Astron. the planet seventh in order from the sun, having an equatorial diameter of 32,600 miles (56,460 km), a mean distance from the sun of 1,784 million miles (2,871 million km), a period of revolution of 84.07 …
73physical science, principles of — Introduction the procedures and concepts employed by those who study the inorganic world. physical science, like all the natural sciences, is concerned with describing and relating to one another those experiences of the surrounding… …
74Spacecraft 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… …
75Apsis — For the architectural term, see Apse. Aphelion and Perihelion redirect here. For Edenbridge s Album, see Aphelion (album). Apogee and Perigee redirect here. For the literary journal, see Perigee: Publication for the Arts. For other uses, see… …
76Graveyard orbit — A graveyard orbit, also called a supersynchronous orbit, junk orbit or disposal orbit, is an orbit significantly above synchronous orbit, where spacecraft are intentionally placed at the end of their operational life. It is a measure performed in …
77earth — /errth/, n. 1. (often cap.) the planet third in order from the sun, having an equatorial diameter of 7926 mi. (12,755 km) and a polar diameter of 7900 mi. (12,714 km), a mean distance from the sun of 92.9 million mi. (149.6 million km), and a… …
78photography, technology of — Introduction equipment, techniques, and processes used in the production of photographs. The most widely used photographic process is the black and white negative–positive system (Figure 1 >). In the camera the lens projects an image of… …
79science, history of — Introduction the history of science from its beginnings in prehistoric times to the 20th century. On the simplest level, science is knowledge of the world of nature. There are many regularities in nature that mankind has had to… …
80Mars Reconnaissance Orbiter — Conceptual image depicting the Mars Reconnaissance Orbiter in an elliptical low planet orbit around Mars Operator NASA / JPL Major contractors Lockheed Ma …
