direct orbit
11direct — /dəˈrɛkt / (say duh rekt), /daɪ / (say duy ) verb (t) 1. to guide with advice; regulate the course of; conduct; manage; control. 2. to give authoritative instructions to: I directed him to do it. 3. to command; order or ordain: I directed that he …
12Retrograde and direct motion — Direct motion is the motion of a planetary body in a direction similar to that of other bodies within its system, and is sometimes called prograde motion. Retrograde motion is motion in the opposite direction. In the case of celestial bodies,… …
13Mars Direct — is a proposal for a manned mission to Mars. Proponents of the scheme have claimed it to be both cost effective and that it can be conducted with current technology. It was originally detailed in a research paper by NASA engineers Robert Zubrin… …
14Lunar orbit rendezvous — (LOR) was the method used by the Apollo missions for human spaceflight to the Moon. In an LOR mission a main spacecraft and a smaller lunar module travel together into lunar orbit (orbit around the Moon). The lunar module then independently… …
15Geocentric orbit — Earth orbit redirects here. For the motion of the Earth around the Sun, see Earth s orbit. Earth orbiter redirects here. For the shuttle simulator, see Earth Orbiter 1. The following words may have more than one definition or other non Earth… …
16Geostationary orbit — Geostationary orbit.To an observer on the rotating Earth (fixed point on the Earth), the satellite appears stationary in the sky. A red satellite is also geostationary above its own point on Earth. Top Down View …
17Molniya orbit — For other uses, see Molniya (disambiguation). Figure 1: The Molniya orbit. Usually the period from perigee + 2 hours to perigee + 10 hours is used to transmit to the northern hemisphere Molniya orbit is a type of highly elliptical orbit with an… …
18Sun-synchronous orbit — Diagram showing the orientation of a Sun synchronous orbit (green) in four points of the year. A non sun synchronous orbit (magenta) is also shown for reference A Sun synchronous orbit (sometimes called a heliosynchronous orbit) is a geocentric… …
19Elliptic orbit — A small body in space orbits a large one (like a planet around the sun) along an elliptical path, with the large body being located at one of the ellipse foci …
20Circular orbit — For other meanings of the term orbit , see orbit (disambiguation) A circular orbit is the orbit at a fixed distance around any point by an object rotating around a fixed axis. Below we consider a circular orbit in astrodynamics or celestial… …
