Outer Planet Missions with Electric Propulsion Systems—Part I

Figure 7

Ratio $m_f/m_i$ for several TOF for a trip to Neptune. The effective specific power $(P)$ used is (a) 4 W/kg (REP), (b) 6.67 W/kg (REP), (c) 40 W/kg (NEP), (d) 50 W/kg (NEP).

(a)

(b)

(c)

(d)