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What is SEP?

asked 2016-05-01 22:27:34 -0600

Pascal Le Dramont gravatar image

What is solar electric propulsion (SEP)?

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answered 2016-05-02 23:27:18 -0600

Rob Mueller gravatar image

Solar electric propulsion (SEP) takes advantage of magnetism and electricity to push a ship through space. Electricity, generated by the ship's solar panels, gives a positive electrical charge to atoms inside the chamber. They are pulled by magnetism towards the back of the ship and then pushed by magnetic repulsion out of the ship. (This is like what happens when you hold the same pole of two different magnets close to each other. They repel each other.) This steady stream of atoms going out of the spacecraft gives it the thrust it needs to go forward through space.

Ref: http://www.qrg.northwestern...

NASA's Solar Electric Propulsion (SEP) project is developing critical technologies to extend the length and capabilities of ambitious new science and exploration missions. Alternative propulsion technologies such as SEP may deliver the right mix of cost savings, safety and superior propulsive power to enrich a variety of next-generation journeys to worlds and destinations beyond Earth orbit.

Energized by the electric power from on-board solar arrays, the electrically propelled system will use 10 times less propellant than a comparable, conventional chemical propulsion system, such as those used to power the space shuttles to orbit. Yet that reduced fuel mass will deliver robust power capable of propelling robotic and crewed missions well beyond low-Earth orbit -- sending exploration spacecraft to distant destinations or ferrying cargo to and from points of interest, laying the groundwork for new missions or resupplying those already underway.


An all-electric satellite dispenses with heavy chemical propulsion and uses electric propulsion not only to maintain itself stably in orbit over 15 years — this has been done by many operators and manufacturers — but also to raise the satellite from where it is dropped into orbit by its carrier rocket to its final destination in geostationary orbit.

Saving all that weight will enable satellite owners to either lower their launch costs or pack more revenue-generating payload onto a satellite for the same launch mass.

The only problem is it takes months, not a couple of weeks, for an all-electric satellite to reach its final operating position.

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Asked: 2016-05-01 22:27:34 -0600

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Last updated: May 02 '16