NEOShield: Design of a Gravity Tractor Demonstration Mission

The Mission Design Division at NASA Ames Research Center has begun a program to develop mission designs for planetary defense. Here we present a mission design for a gravity tractor demonstration mission completed in collaboration with the European NEOShield consortium.We conducted a trade study to identify suitable target NEOs to demonstrate GT deflection, and identified 5 known asteroids with diameters between 100m and 500m that have been well studied in the past: 2000 FJ10, 2001 QC34, 2002 DU3, 2001 JV1 and 1998 VO. We selected 2000 FJ10 as the most suitable target to meet the requirements of a GT demonstration mission.Our GT demonstration spacecraft is based on an ESPA ring main structure and solar electric propulsion (SEP, see Figure 1). The power budget is 4 kW and the spacecraft has an initial wet mass of 1,150 kg. The spacecraft would launch in the 3rd quarter of 2026 aboard a Falcon 9, arriving at 2000 FJ10 in early 2029 after an unpowered Mars gravity assist in 2027. The spacecraft mass at asteroid arrival would be 1,100 kg.