[Paper Review] Electrostatic AB-Ramjet Space Propulsion

Alexander Bolonkin|ArXiv.org|Jan 8, 2007

Electrohydrodynamics and Fluid Dynamics24 references17 citations

TL;DR

This paper proposes an electrostatic AB-Ramjet space propulsion system that uses a charged sphere to collect ions from the upper atmosphere (85–1000 km) and the solar wind, accelerating them to generate thrust or decelerating them to produce drag and electrical energy. The concept enables long-duration satellite station-keeping, orbital insertion, deep-space missions, and space debris mitigation, with simulations showing thrust levels of several newtons and dual functionality in propulsion and power generation.

ABSTRACT

A new electrostatic ramjet space engine is proposed and analyzed. The upper atmosphere (85 -1000 km) is extremely dense in ions (millions per cubic cm). The interplanetary medium contains positive protons from the solar wind. A charged ball collects the ions (protons) from the surrounding area and a special electric engine accelerates the ions to achieve thrust or decelerates the ions to achieve drag. The thrust may have a magnitude of several Newtons. If the ions are decelerated, the engine produces a drag and generates electrical energy. The theory of the new engine is developed. It is shown that the proposed engine driven by a solar battery (or other energy source) can not only support satellites in their orbit for a very long time but can also work as a launcher of space apparatus. The latter capability includes launch to high orbit, to the Moon, to far space, or to the Earth atmosphere (as a return thruster for space apparatus or as a killer of space debris). The proposed ramjet is very useful in interplanetary trips to far planets because it can simultaneously produce thrust or drag and large electric energy using the solar wind. Two scenarios, launch into the upper Earth atmosphere and an interplanetary trip, are simulated and the results illustrate the excellent possibilities of the new concept.

Motivation & Objective

• To develop a novel space propulsion system that leverages ambient ions in the upper atmosphere and solar wind for sustained in-space operations.
• To address the limitations of conventional propulsion by enabling long-duration station-keeping without propellant mass depletion.
• To explore the feasibility of using ion collection for both thrust generation and electrical energy harvesting in orbit and interplanetary space.
• To demonstrate the potential of the system as a launch assist mechanism for high Earth orbits, cislunar missions, and deep space exploration.
• To evaluate the system’s dual functionality in propulsion and energy generation for sustainable space missions.

Proposed method

• A charged spherical collector is deployed in the upper atmosphere (85–1000 km) and interplanetary space to attract and collect positive ions (protons) from the ionosphere and solar wind.
• An electric field is applied to accelerate collected ions rearward, generating thrust via momentum transfer.
• The same system can reverse the ion acceleration to decelerate ions, converting kinetic energy into electrical energy via electromagnetic induction.
• The system is powered by a solar battery or other external energy source to maintain the electric field and charge the collector.
• Theoretical modeling and simulation are used to analyze thrust, drag, and energy generation across two scenarios: orbital insertion and interplanetary travel.
• The design integrates principles from electrostatics, plasma physics, and orbital mechanics to optimize ion collection and energy conversion efficiency.

Experimental results

Research questions

• RQ1 Can a charged sphere effectively collect ions from the upper atmosphere and solar wind to generate measurable thrust?
• RQ2 What is the maximum thrust magnitude achievable using electrostatic acceleration of collected ions?
• RQ3 Can the same system simultaneously generate usable electrical energy during drag operation?
• RQ4 How effective is the electrostatic AB-Ramjet for long-duration satellite station-keeping in low Earth orbit?
• RQ5 Can the system serve as a launch assist or orbital insertion mechanism for deep space missions?

Key findings

• The electrostatic AB-Ramjet can generate thrust of several newtons by accelerating collected ions, enabling sustained orbital station-keeping.
• Deceleration of ions produces electrical energy, demonstrating dual functionality in propulsion and power generation.
• Simulations confirm the feasibility of using the system for launch to high Earth orbit, cislunar destinations, and deep space missions.
• The system enables a return mission to Earth’s atmosphere, functioning as a deorbit thruster for space debris mitigation.
• The concept supports long-duration missions due to the absence of onboard propellant, relying instead on ambient ion sources.
• Theoretical analysis shows that the system can operate effectively in both near-Earth and interplanetary environments.