Testing the first electrostatic radiation shield in deep space

Can we have Star Trek-style radiation shields on future space missions?

Earth-inspired solution to a space problem

Traditionally, protection from space radiation for astronauts and electronics of spacecrafts has been material-based (usually lead) a.k.a. passive shielding. Team EARS wants to use something that isn’t material-based, drawing inspiration from the natural shielding that our Earth has had for billions of years.

An artist’s depiction of the Earth’s magnetic field protecting itself from solar charged particles. White lines — solar radiation, purple line — bow shock, blue lines — Earth’s magnetic field. Image not to scale. Source: Wikipedia
Styrofoam peanuts clinging to a cat’s fur due to static electricity. Source: Wikipedia

The setup

The soda-can sized EARS experiment consists of a Van de Graaff generator capable of generating a 450 kV voltage. Here is what the setup looks like:

A miniature Van de Graaff generator storing positive charge on the sphere-shaped conductor at the top. Electric motor (bottom right) and gears run the rubber belt.
The two sensors on the top deck to monitor incoming charged particles.

How it works

When the conducting sphere is fully charged, the electrostatic field created will engulf the sensors. The positively-charged sphere will attract negative particles (like electrons) in space radiation and the sensors will detect them. Positively-charged particles (like protons) will get deflected due to electrostatic repulsion.

A charged particle is deflected by an electrostatic field. Source: Quora
A Bion satellite, part of the Soviet space program focused primarily on biological experiments. Source: Wikipedia

Advantages of an active radiation shield

There are numerous advantages of an active shield over a static one.

  1. Active shielding is cheaper than material-based shielding for the same amount of efficiency due to reduced material cost.
  2. The ability of a material-based shield to protect from radiation deteriorates with time. For long space missions, a self-sustainable active shield is thus more effective and reliable.
  3. An active shield reduces launch cost as the significant mass of a passive shield is reduced.


The potential applications of an active radiation shield are numerous. The habitable modules of future lunar colonies can be protected using such a shield. Even manned rovers being driven on the lunar surface could make use of it. The EARS experiment, while small, will lay the groundwork to determine the full-scale requirement of employing a radiation shield capable of protecting future lunar colonies.

Concept of an electrostatic shield for a lunar base using charged spheres. Source: SlideShare

The next steps

Simulations of the EARS experiment using Strontium-90 as radiation source has yielded positive results (pun intended). The next step is to test the experiment on the particle accelerator “Microtron” available at the University of Pune. The conditions in the vacuum of the accelerator closely mimic the lunar environment. After that, Team EARS will be ready to fly to the Moon in 2018 and take their moonshot.


Van de Graaff generators saw their first application as particle accelerators. From being the first particle accelerators to potentially accelerating the future of space exploration and settlement, the Van de Graaff generator has been one neat invention. Who wouldn’t like to have Star Trek-style radiation shields? I know I would.

Illustration of an electrostatic field surrounding the Star Trek spaceship U.S.S Enterprise. Source: HowStuffWorks



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Jatan Mehta

Space and Moon exploration writer ~ Contributing Editor, The Planetary Society ~ Thinker | Website: https://jatan.space