Electromagnetic shield against space radiations

Davide Micheli, Mario Marchetti

Università "La Sapienza" di Roma

Graziano Cerri

Università Politecnica delle Marche

The space radiations effect is one of the main problems concerning astronaut's health and onboard electronic equipment's functionality like computers, sensors, and so on. Radiations cause ionization in biological matter and charge deposition in semiconductors. It is one of the main threats to space activities as well as to Moon and Mars human colonization. There are many publications about passive and active methods studied in order to attenuate/deflect radiations flux. Here after a new approach based on an active Electromagnetic system is presented. It is able to deflect incoming energetic particles i.e. space ionizing radiations. The principle is based on electromagnetic circularly polarized wave emitted by an antenna located close to the target we want protect from incoming charged particle impact.

The charged particles type which this system is able to deflect is mainly a function of the particle energy. The deflection amplitude is also function of electrical power at antenna input, antenna system gain as well as the frequency of electromagnetic wave emitted by antenna system. The system presented here after can deflect low Solar Wind charged particles energy level.

The solar wind is a stream of mostly charged particles that emanate from the Sun and blow throughout the Solar System. The solar wind is not uniform. Although it is always directed away from the Sun, it changes speed and carries with it magnetic clouds, interacting regions where high speed wind catches up with slow speed wind, and composition variations. The solar wind speed is high (800 km/s) over coronal holes and low (300 km/s) over streamers. These high and low speed streams interact with each other and alternately pass by the Earth as the Sun rotates. These wind speed variations buffet the Earth's magnetic field and can produce storms in the Earth's magnetosphere.

One new approach to the radioactive charged particles protection problem solution could be studied by using an antenna irradiating an EM (Electromagnetic) wave circularly polarized. The useful effect is a trajectory deflection of each single energetic particle from its original trajectory. In this way, by deflecting the energetic charged particles, it could be possible to protect a certain target from the energetic particles impact.

Trial results seem to confirm theoretical mathematical model for deflection of a charged particle. Using circularly polarized electromagnetic field it is possible to deflect a charged particle from its original trajectory. In future Space applications (e.g. on the Moon or Mars), an array of antennas could be designed in order to increase the overall gain of antenna system, in fact the more is the antenna gain the higher is the charged particle deflection.