In order to meet survivability requirements, probability of impact and failure analysis has led to ballistic limit thresholds (cometary particle diameter and velocity) for which a Stardust shield must be infallible. For example, the Stardust Main Shield (SMS) shown at right, was tested to determine its ballistic limit.

The SMS with dual layer Nextel and Launch Vehicle Adapter shield configuration was capable of withstanding an impact by a 3.57 mm (9/64") nylon projectile traveling at 5.92 km/s, which is within the predefined requirement.

The SMS with dual layer Nextel offers inadequate protection against a 10 mm nylon projectile traveling a 6 km/s. In the first of two tests, no perforating debris was generated and the target was deemed to pass. In the confirmation test, the projectile inflicted significant damage to the rear wall. Hence, it was decided to augment the SMS with an additional layer of Nextel.