Circumlunar trajectory — The trajectory followed by Apollo 13 A Circumlunar trajectory, Trans Lunar trajectory or Lunar free return is a type of free return trajectory which takes a spacecraft from Earth, around the far side of the Moon, and back to Earth. Background The … Wikipedia
free-re|turn trajectory — «FREE rih TURN», the trajectory of a spacecraft toward a lunar or planetary orbit which provides for an automatic return to earth if the spacecraft is unable to enter the proper orbit … Useful english dictionary
Free-fall time — The free fall time is the characteristic time that would take a body to collapse under its own gravitational attraction, if no other forces existed to oppose the collapse. As such, it plays a fundamental role in setting the timescale for a wide… … Wikipedia
Gravity turn — A gravity turn or zero lift turn is a maneuver (see trajectory optimization) used in launching a spacecraft into, or descending from, an orbit around a celestial body such as a planet or a moon. This launch trajectory offers two main advantages… … Wikipedia
Moon landing — For other uses, see Moon landing (disambiguation). Still frame from the video transmission of Neil Armstrong stepping onto the surface of the Moon at 02:56 UTC on 21 July 1969. An estimated 500 million people worldwide watched this event,… … Wikipedia
Trans Lunar Injection — Typical lunar transfer trajectories approximate Hohmann transfers, although low energy transfers have also been used in some cases, as with the Hiten probe. [cite web |url=http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1990 007A… … Wikipedia
Lunar orbit — In astronomy, lunar orbit (also known as a Selenocentric orbit) refers to the orbit of an object around the Moon.As used in the space program, this refers not to the orbit of the Moon about the Earth, but to orbits by various manned or unmanned… … Wikipedia
Apollo 13 — Infobox Space mission mission name = Apollo 13 insignia = Apollo 13 insignia.png stats ref = cite web |url=http://history.nasa.gov/SP 4029/Apollo 00g Table of Contents.htm |title= Apollo by the Numbers: A Statistical Reference (SP 4029)… … Wikipedia
Mars for Less — (MFL) [1][2]is a proposal for a near term human Mars expedition that involves the use of existing Evolved Expendable Launch Vehicles (EELVs, or alternatively, Medium Lift Launch Vehicles, MLLVs). The MFL plan claims that the barrier to entry for… … Wikipedia
PAS-22 — AsiaSat 3 → HGS 1 → PAS 22 Operator AsiaSat (1997–1998) Hughes (1998–1999) … Wikipedia