High resolution imaging of hypervelocity impacts

Louise Smyth

The Institute of Astronautics, Technical University of Munich, Germany has used a SIM-X ultra-high speed framing camera to record high resolution images of hypervelocity impacts on granular media samples with different bulk densities.

At the Institute of Astronautics, research to investigate principles for lunar in-situ resource utilisation (ISRU) has been conducted.

Lunar regolith provides a multitude of elements which are bound in ores and minerals. The thermal, chemical and mechanical properties, however may change significantly upon the high pressures of a hypervelocity impact.

To simulate this process, impact tests were carried out using 25mg Polyethylene or 73mg Aluminium cyliders fired at 1-4 Km/sec at lunar granular material simulant (JSC-1A) under vacuum conditions.

Through undertaking these experiments the researchers sought to measure the velocity and angle of materials ejected as a result of hypervelocity impact to see if the ejecta might be lost from the lunar surface into space.

The main diagnostic tool used for the impact experiments was a Specialised Imaging SIM-X ultra-high speed framing camera.

The camera features up to 16 discrete intensified optical channels with an image size of 1360 x 1024 pixels at 12-bit resolution. Each frame can be programmed individually concerning gain and exposure to optimise data capture.

With a minimum interframe tome of just 5 ns the SIM-X can capture high quality images to help unlock the secrets of even the most fleeting pof events. The illumination of the simulated lunar surface impact event was realised using two high power flash heads with a total light duration of about 4ms.