Design Blueprint: Solar-Sail Transfer of a Retired Geostationary Satellite to a Graveyard Orbit

Design blueprint derived from the source paper (DOI 10.5281/zenodo.24182931): This paper presents a computed design study of a civilian orbital-safety system based on solar radiation pressure on a large reflective sail. It is a computed study of a civilian orbital-safety system, with no targeting application and no weapon application. Status: SIMULATED, NOT MEASURED. Under the stated assumptions the sizing gives a sail force N of 0.00327, a acceleration m per s2 of 1.82e-06, and a characteristic accel mm per s2 of 0.00182. Further computed quantities include transfer delta v m per s of 27.2; spiral time days of 347; sail area m2 of 400; areal loading g per m2 of 4.5e+03. The design is sized end to end from the stated assumptions in the deposited computation, so every headline number can be reproduced, challenged and revised. Where the approach performs poorly, that result is reported at the same size as the favourable results: the limitations section names the conditions under which this design should not be chosen. The contribution is a complete, auditable sizing for one operating principle, intended to be compared like-for-like with sizings built on other principles for the same task. Status: DESIGN BLUEPRINT — SIMULATED, NOT MEASURED — NOT BUILT. All numbers are simulated values from the source paper's computation, deposited with this blueprint as compute.py and results.json. AI-use disclosure: Dave, an AI research system, assisted with the computation and drafting under the author's direction; author of record William Alexander Aldred.