spacecraft A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, p ...

operations, Launch and Early Operations (LEOP) is one of the most critical phases of a mission. Spacecraft operations

engineers Engineers, as practitioners of engineering, are professionals who invent, design, analyze, build and test machines, complex systems, structures, gadgets and materials to fulfill functional objectives and requirements while considering the ...

take control of the

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioi ...

after it separates from the

launch vehicle A launch vehicle or carrier rocket is a rocket designed to carry a payload ( spacecraft or satellites) from the Earth's surface to outer space. Most launch vehicles operate from a launch pads, supported by a launch control center and ...

. LEOP generally concludes once the satellite is safely positioned in its final

orbit In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as ...

. During this period, operations staff work typically 24 hours a day to activate, monitor and control the various subsystems of the satellite, including the deployment of any satellite appendages (such as

antennas In radio engineering, an antenna or aerial is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver. In transmission, a radio transmitter supplies an ...

solar arrays A photovoltaic system, also PV system or solar power system, is an electric power system designed to supply usable solar power by means of photovoltaics. It consists of an arrangement of several components, including solar panels to absorb and c ...

, reflectors, and radiators), and undertake critical orbit and

attitude control Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle ...

manoeuvres. Extra support staff are typically on hand and

on-call On-call scheduling, sometimes referred to as on-call shifts, are processes used in business where employee work schedules are intentionally unpredictable. Employees who work on-call are expected to be available at any time during their shift, usu ...

during LEOP, relative to staffing during normal operations. For

geostationary satellites A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude ...

, the launch vehicle typically carries the spacecraft to Geostationary Transfer Orbit, or GTO. From this

elliptical Elliptical may mean: * having the shape of an ellipse, or more broadly, any oval shape ** in botany, having an elliptic leaf shape ** of aircraft wings, having an elliptical planform * characterised by ellipsis (the omission of words), or by conc ...

orbit, the LEOP generally includes a sequence of

apogee engine An apogee kick motor (AKM) is a rocket motor that is regularly employed on artificial satellites to provide the final impulse to change the trajectory from the transfer orbit into its final (most commonly circular) orbit. For a satellite laun ...

firings to reach the circular geostationary orbit.

References

ESA Spacecraft Operations website
Spaceflight concepts Spaceflight

See also

References