Solar sail

(Last edited: Monday, 2 October 2023, 6:00 PM)
Source: Midjourney (2023, May 31). . midjourney.

Source: Midjourney (2023, May 31). . midjourney.

Short Definition:

Solar sails (also known as light sail or photon sail) are a method of spacecraft propulsion using radiation pressure exerted by starlight on large mirrors. Solar sails can be used instead of traditional fuel consumption. First proposed in the 1980s as alternative propulsion method for low-weight long-distance spacecrafts, the first real usage of the solar sail system was in JAXA’s IKAROS mission, launched in 2010.

Detailed Definition:

The Solar sails use a phenomenon called solar pressure, which is the force produced by the impact of sunlight photons on the surface of the spacecraft. Normally, solar pressure is affecting all spacecrafts during flights and must be accounted for in trajectory planning, but in that specific case it is used as thrust. Vessels using solar sails must be lightweight as the total force exerted on an eight hundred by eight hundred meters solar sail is about 5 Newtons at Earth's distance from the Sun, so this propulsion method requires specially constructed spacecraft. If solar sails are implemented in space vessel it can produce propulsion without need of fuel usage and thus can be great for small satellites to travel to distant objects without great amount of storage for fuel and engines. The negative side of this technology is significantly small force compared to traditional liquid fuel engines and fragile sail build. Also, this system cannot be used far away from “propulsion” star, as thrust generated by the solar sail is inversely proportional to the square of the distance.


Solar - From Latin sōlāris, from sōl (“sun”),
Sail - From Middle English saile, sayle, seil, seyl, from Old English seġl

Sample Sentence(s):

“The IKAROS probe is the world's first spacecraft to use solar sailing as the main propulsion system.”
“Solar sail is the more effective the closer it is to the star.”



Voile solaire




Żagiel słoneczny


Sol segel

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