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The problem of simulating the interaction of spacecraft travelling atvelocities necessary for starflight with the interplanetary and interstellarmedium is considered. Interaction of protons, atoms, and ions at kineticenergies relative to the spacecraft (MeV per nucleon) is essentially a problemof sputtering. More problematic is the impact of dust grains, macroscopicobjects on the order of 10 nm ($10^{-21}$ kg) to 1 $\mu$m ($10^{-15}$ kg), theeffects of which are difficult to calculate, and thus experiments are needed.The maximum velocity of dust grains that can be achieved at present in thelaboratory using electrostatic methods is approximately 100 km/s, two orders ofmagnitude below starflight velocities. The attainment of greater velocities hasbeen previously considered in connection with the concept of impact fusion andwas concluded to be technologically very challenging. The reasons for this areexplained in terms of field emission, which limits the charge-to-mass ratio onthe macroscopic particle being accelerated as well as the voltage potentialgradient of the accelerating electrostatic field, resulting in the acceleratorneeding to be hundreds to thousands of kilometers long for $\mu$m-sized grains.Use of circular accelerators (cyclotrons and synchrotrons) is not practical dueto limitations on magnetic field strength making the accelerator thousands ofkilometers in size for $\mu$m-sized grains. Electromagnetic launchers(railguns, coilguns) have not been able to produce velocities greater thanconventional gas guns (< 10 km/s). The nearest feasible technologies (tandemaccelerators, macromolecular accelerators) to reach the regime of projectilemass and velocity of interest are reviewed. Pulsed lasers are found to be theonly facilities able to accelerate condensed phase matter to velocitiesapproaching 1000 km/s but unlikely to be able to reach greater speeds.

Experimental Simulation of Dust Impacts at Starflight Velocities