Preliminary dust-impact risk study for the “Solar Probe” spacecraft

Solar Probe is a mission currently under study, funded by the NASA's Office of Space Science—Sun–Earth Connection theme. This mission seeks to achieve the first visit to the Sun to explore the physical phenomenon that occurs at close proximity to our star. The mission requires the spacecraft to follow a polar orbit around the Sun with a perihelion of four (4) solar radii. A flyby at this close distance from the Sun will put the spacecraft under extraordinary environmental loads. One of the concerns is the effect that interplanetary and interstellar dust will have on the integrity of the spacecraft. The maximum dust impact velocity is expected to be around 500 km/s. This velocity is well above current experimental capabilities—more than an order of magnitude higher. For this reason, numerical simulations appear to be the best tool to determine the expected level of damage generated by the solar dust on the structural components and instruments of the Solar Probe spacecraft. Presented here are the results of the analysis of the dust environment to be experienced by the spacecraft and the shielding design parameters for different components. The design parameters of various structural components and instruments were used to conduct computer simulations using CTH to study shielding concepts.