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In this answer to Do you need 0 km/s velocity to crash into the sun? I mention solar sails for retrograde thrust and the Poynting–Robertson as two ways an object could ever-so-slowly spiral into the Sun.

Using known materials with modest extrapolations (like they do for solar sails) and ignoring deterioration due to solar wind, radiation damage and meteorites, is there some mass regime where a configuration optimized for Poynting–Robertson effect would be faster than a configuration optimized for a vanilla solar sail to get from a 1 AU orbit to the Sun?

For example, if two teams were assigned the task of designing a passive Sun-spiraling craft and given the same mass constraint, would the SolarSailors team always win no matter what mass was choses, or are there some masses where the PoyntingRobertsons could win?


Possibly helpful:

Solar sail:

Poynting–Robertson drag:

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No. Let's take the "tacking against the Sun" scenario.

The optimal incidence angle for a 100% reflective solar sail to reduce orbital velocity around the Sun, is 45 degrees, all of the reflected incident rays reflected 90 degrees prograde, maximum retrograde thrust. Any more or any less and some of the thrust would have useless radial component. For less than 100% reflective the angle might be slightly higher; all of the absorbed light provides useless radial-out thrust, but it will be re-radiated perpendicular to the sail (on the average), so giving it a little of prograde bias at cost of losing out some on the reflected might provide beneficial; nevertheless the reflected light provides far more momentum so the aim will be to get as close to 100% reflectivity as possible.

On the other hand, Poynting–Robertson effect is equivalent to the same but at incidence angle of $arctan({c \over 29.7 km/s})$, that is about 89.994 degrees. Almost but not quite the completely useless 90 degrees where none of the light would contribute retrograde thrust and in fact none would hit the sail surface.

That is even ignoring the impossible engineering challenge of having the "Poynting–Robertson sail" have the reflected light not hit any other part of the craft; doable in case of sparse loose dust, not a structurally solid macroscopic spacecraft.

SF.
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