Page:Project Longshot - Advanced Design Program Project Report.pdf/62

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Rough calculations for Delta-V's for orbit changes to take the probe out to Jupiter (to take on fuel) are made using Hohmann transfer equations as an approximation (actual orbits would be patched-conics). The first six calculations are the same for this analysis:

(1) Energy of Hohmann transfer orbit:
Et = −fsun/6.2 AU = −143.0894 km2/sec2
(2) Perigee velocity of transfer orbit:
V1 = [2(fsun/1 AU + Et)].5 = 38.6171 km/sec
(3) Delta-V to enter transfer orbit:
Delta-V1 = V1 − Vp−sun = 8.8223 km/sec
(4) Apogee velocity of transfer orbit:
V2 = [2(fsun/5.2 AU + Et)] = 7.4157 km/sec
(5) Velocity required to orbit Jupiter at an altitude of 500,000 km:
V3 = (fJupiter/571370).5 = 14.8971 km/sec
(6) Delta-V to inject into orbit about Jupiter:
V3 − V2 = 7.4814 km/sec
(7) Jupiter escape velocity:
V3−escape = (2fJupiter/571370).5 = 21.0676 km/sec
(8) Delta-V to escape Jupiter:
Delta-V3−esc = VJ−esc − VJ = 6.1705 km/sec
(9) Velocity of probe about sun at Jupiter distance:
Vp−sun−J = (fsun/5.2 AU).5 = 13.0601 km/sec