Resiliency of Electronics
Radiation levels along the trajectory of the probe
From the perspective of robustness of electronics, the Space Buster exoplanet mission can be partitioned into three regions of interest. In the first region, the spacecraft is subjected to the Van Allen belt radiation as well as radiation from solar events. The second region lies in the vast emptiness in between our sun and Epsilon Eridani. The final region is at the destination, as our spacecraft orbits Epsilon Eridani and must remain functional.
The Space Buster probe will be designed using a worst case scenario approach. Its electronics will be designed to withstand the region in which the probe will experience the most severe levels of radiation. Because the probe will not closely orbit either the Sun or Epsilon Eridani, this region will likely be the space between the stars where galactic cosmic radiation is present. However, the nuclear propulsion system will also be an extremely powerful source of radiation. The electronics will be hardened to withstand whichever represents the worst case scenario.
No manmade probe has yet been sent very far away from the Sun. Voyager 1 is the farthest yet at a distance of only 116 AU away. Therefore, limited data is available on the radiation level between the stars. However, the International Organization for Standardization ISO Model 15390 2004 provides a useful model for the galactic cosmic rays.
Susceptible Components
Unfortunately, the most critical components to the Space Buster mission will also be the most susceptible to failure by radiation. The small spacing between the circuit elements of integrated circuits make them susceptible to failure by short circuiting and parasitic effects. Under this category would fall DSP filters and microprocessors. Crystal oscillators can also be easily damaged, which are vital to providing the carrier frequency used to relay the signal.