Ad Astra’s VASIMR® Space Tug: A Cost-Efficient Low Earth Orbit Space Cleaner
Abstract
This paper describes the mission architecture and advantages of the Variable Specific Impulse Magnetoplasma Rocket (VASIMR)® propulsion technology to remove orbital debris from low Earth orbit (LEO) using a solar electric propulsion (SEP) space tug. Ad Astra has examined the capture and deorbiting of several items of orbital debris (Zenit rocket upper stages) orbiting in high inclination orbits. The mission concept presented here utilizes the 200 kW VASIMR® SEP space tug to lower the altitude of Zenit stages for a controlled deorbit over the Pacific Ocean. To achieve this, the tug is fitted with a mission-specific service module (SM) comprising a solid rocket motor (SRM) tray loaded with detachable, short-range, chemical robotic pods (CRP) for operations near the stages. For each target, the tug climbs to the drifting Zenit (~800 km) where the CRP captures, stabilizes, and retrieves the target to a hard docking with the tug. After capture, the CRP robotically installs a replacement SRM unit onto the Zenit rocket nozzle. With the Zenit attached, the tug brings it down to ~400 km for release, at which point the SRM ignites, bringing the Zenit to an atmospheric re-entry. The tug then climbs back to ~800 km to capture the next target and repeats the process. The mission is optimized for minimum fuel use and minimum time for a given power and specific impulse (Isp) that is ideally suited for a VASIMR® propulsion system which will be at Technology Readiness Level (TRL) 5 following successful completion of a long duration NASA test run later in 2015. The advantages and disadvantages of the VASIMR SEP are also compared against other orbital debris technologies such as ElectroDynamic Debris Eliminator (EDDE), Swiss Space Systems (S3) and Space Debris Elimination (SpaDE).
Ad Astra’s VASIMR® Space Tug: A Cost-Efficient Low Earth Orbit Space Cleaner
This paper describes the mission architecture and advantages of the Variable Specific Impulse Magnetoplasma Rocket (VASIMR)® propulsion technology to remove orbital debris from low Earth orbit (LEO) using a solar electric propulsion (SEP) space tug. Ad Astra has examined the capture and deorbiting of several items of orbital debris (Zenit rocket upper stages) orbiting in high inclination orbits. The mission concept presented here utilizes the 200 kW VASIMR® SEP space tug to lower the altitude of Zenit stages for a controlled deorbit over the Pacific Ocean. To achieve this, the tug is fitted with a mission-specific service module (SM) comprising a solid rocket motor (SRM) tray loaded with detachable, short-range, chemical robotic pods (CRP) for operations near the stages. For each target, the tug climbs to the drifting Zenit (~800 km) where the CRP captures, stabilizes, and retrieves the target to a hard docking with the tug. After capture, the CRP robotically installs a replacement SRM unit onto the Zenit rocket nozzle. With the Zenit attached, the tug brings it down to ~400 km for release, at which point the SRM ignites, bringing the Zenit to an atmospheric re-entry. The tug then climbs back to ~800 km to capture the next target and repeats the process. The mission is optimized for minimum fuel use and minimum time for a given power and specific impulse (Isp) that is ideally suited for a VASIMR® propulsion system which will be at Technology Readiness Level (TRL) 5 following successful completion of a long duration NASA test run later in 2015. The advantages and disadvantages of the VASIMR SEP are also compared against other orbital debris technologies such as ElectroDynamic Debris Eliminator (EDDE), Swiss Space Systems (S3) and Space Debris Elimination (SpaDE).
