Space: Science & Technology / 2021 / Article / Tab 3

Review Article

Application Prospect of Fission-Powered Spacecraft in Solar System Exploration Missions

Table 3

Kuiper Belt Object Orbiter (KBOO) comparison of Radioisotope Electric Propulsion (REP) and Fission Electric Propulsion (FEP).

Power systemREPFEP

Science and mission duration100 kg CBEa/16 yr trip, 1 yr science100 kg CBE/16 yr trip, 1 yr science
Launch vehicleDelta IV Heavy/Star 63FDelta IV Heavy/Star 63F
Launch mass (kg)31003700
Power level (EOLb)/mass αNine, 550 W ASRGc, 4000 We/782 kg (5 We/kg)Single fast reactor, Stirling convertors 8000 We/1162 kg (7 We/kg)
Electric propulsion trust/weight1+1 3000 W NEXTd Ion, ~1200 kg Xe1+1 7000 W NEXTd Ion, direct drive, ~1200 kg Xe
Height (m)
 Deployed616
 Launch37
Nuclear material~27 kg, 238Pu~75 kg, 93% HEUe
Initial radioactivity (Ci)4132604.8

aCurrent best estimate. bEnd of life. cAdvanced Stirling Radioisotope Generator. dNASA’s Evolutionary Xenon Thruster. eHighly enriched uranium.