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<strong>for</strong> each trajectory leg. Once again, all possible combinations were analyzed to have a<br />

basis <strong>for</strong> evaluation of the per<strong>for</strong>mances of the <strong>pruning</strong> <strong>and</strong> <strong>global</strong> <strong>optimization</strong> phases.<br />

The best solution visits the following asteroids: 2006 QQ56 – Medusa – Kostinsky. The<br />

<strong>space</strong>craft departs Earth on March 1, 2015 with a launch V ∞ of 2.59 km/s. The time of<br />

flight <strong>for</strong> each leg is 600 days, 1600 days, <strong>and</strong> 1200 days, respectively. The total mission<br />

time is 3580 days, which includes the two 90-day stay times at each asteroid, <strong>and</strong> the<br />

arrival mass is 903 kg. This is actually the same optimal solution as <strong>for</strong> the small sample<br />

problem, <strong>and</strong> is plotted in Figure 19.<br />

Table 8: Ten best asteroid combinations <strong>for</strong> intermediate problem ranked by final mass.<br />

Earth Dep.<br />

Leg 1 TOF Leg 2 TOF Leg 3 TOF Mf<br />

Ast. 1 Ast. 2 Ast. 3<br />

Date<br />

(days) (days) (days) (kg)<br />

03/01/2015 2006 QQ56 Medusa Kostinsky 600 1600 1200 904<br />

01/01/2015 2004 VJ1 Medusa Kostinsky 500 1800 1200 870<br />

08/22/2016 2006 QQ56 Hertha Telamon 600 1800 1200 856<br />

03/05/2020 2006 FH36 Medusa Potomac 500 1800 1200 843<br />

03/29/2021 Apophis Hertha P<strong>and</strong>arus 300 1800 1200 843<br />

10/12/2018 2006 FH36 Geisha Kostinsky 500 1800 1200 834<br />

01/01/2015 2002 AA29 Medusa Kostinsky 600 1700 1200 831<br />

09/11/2018 2006 QQ56 Geisha Kostinsky 600 1700 1200 826<br />

06/12/2024 2004 VJ1 Medusa Potomac 600 1800 1200 820<br />

08/28/2015 2006 QQ56 Geisha Caltech 600 1700 1200 812<br />

Table 9: Orbital elements of asteroids in Table 9, in the J2000 heliocentric ecliptic frame.<br />

Asteroid<br />

semi-major<br />

inclination longitude of the Argument of<br />

Group #<br />

eccentricity<br />

Name<br />

axis (AU)<br />

(deg) asc. node (deg) periapsis (deg)<br />

2006 QQ56 4 0.987 0.047 2.83 163.33 332.96<br />

2002 AA29 4 0.994 0.013 10.74 106.47 100.61<br />

Apophis 4 0.922 0.191 3.33 204.46 126.40<br />

2004 VJ1 4 0.944 0.164 1.29 233.54 332.36<br />

2006 FH36 4 0.954 0.199 1.59 280.92 154.81<br />

Geisha 2/3 2.24 0.193 5.66 78.34 299.88<br />

Medusa 2/3 2.17 0.065 0.937 159.65 251.13<br />

Hertha 2/3 2.43 0.207 2.31 343.90 340.04<br />

Kostinsky 1 3.99 0.220 7.64 257.11 163.00<br />

Telamon 1 5.17 0.108 6.09 341.01 111.19<br />

P<strong>and</strong>arus 1 5.17 0.068 1.85 179.86 37.74<br />

Caltech 1 3.16 0.114 30.69 84.61 294.92<br />

Potomac 1 3.98 0.181 11.40 137.51 332.82<br />

95

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