An orbit descent system for space debris, the system comprising: an artificial satellite; an electroconductive tether extendably held by the artificial satellite; wherein an electron collector is formed on one end of the electroconductive tether or a part of the electroconductive tether; an electroconductive tether attachment mechanism; an electroconductive tether extension mechanism (3, 8), and an electron emitter electrically connected to another end of the electroconductive tether for emitting electrons to ambient plasma in order to form a pseudo closed circuit through the electron emitter, the ambient plasma, the electron collector and the electroconductive tether, wherein the system is configured so that the artificial satellite approaches space debris orbiting around a heavenly body, the electroconductive tether attachment mechanism attaches one end of the electroconductive tether to the space debris, and further, the electroconductive tether extension mechanism (3, 8) extends the electroconductive tether with the other end thereof held by the artificial satellite, whereby the orbits of the integrated and orbiting artificial satellite, electroconductive tether and space debris are caused to descend toward the heavenly body, by action of an electromagnetic effect of a magnetic field around the heavenly body upon the extended electroconductive tether, the electromagnetic effect being such that the magnetic field causes an induction current through the pseudo closed circuit formed by the electrons emitted by the electron emitter resulting in a Lorentz force from the magnetic field causing the orbits of the integrated and orbiting artificial satellite, electroconductive tether and space debris to descend, and the orbital motions of the integrated and orbiting artificial satellite, electroconductive tether and space debris are changed under control by the artificial satellite, wherein the system is configured to change the orbital motions of the integrated and orbiting artificial satellite, electroconductive tether and space debris, by a propulsion system comprised in the artificial satellite. an artificial satellite; an electroconductive tether extendably held by the artificial satellite; wherein an electron collector is formed on one end of the electroconductive tether or a part of the electroconductive tether; an electroconductive tether attachment mechanism; an electroconductive tether extension mechanism (3, 8), and an electron emitter electrically connected to another end of the electroconductive tether for emitting electrons to ambient plasma in order to form a pseudo closed circuit through the electron emitter, the ambient plasma, the electron collector and the electroconductive tether, wherein the system is configured so that the artificial satellite approaches space debris orbiting around a heavenly body, the electroconductive tether attachment mechanism attaches one end of the electroconductive tether to the space debris, and further, the electroconductive tether extension mechanism (3, 8) extends the electroconductive tether with the other end thereof held by the artificial satellite, whereby the orbits of the integrated and orbiting artificial satellite, electroconductive tether and space debris are caused to descend toward the heavenly body, by action of an electromagnetic effect of a magnetic field around the heavenly body upon the extended electroconductive tether, the electromagnetic effect being such that the magnetic field causes an induction current through the pseudo closed circuit formed by the electrons emitted by the electron emitter resulting in a Lorentz force from the magnetic field causing the orbits of the integrated and orbiting artificial satellite, electroconductive tether and space debris to descend, and the orbital motions of the integrated and orbiting artificial satellite, electroconductive tether and space debris are changed under control by the artificial satellite, wherein the system is configured to change the orbital motions of the integrated and orbiting artificial satellite, electroconductive tether and space debris, by a propulsion system comprised in the artificial satellite.