All-Axis Light Gas Gun

Hypervelocity Impact Testing

The All-Axis Light Gas Gun (AALGG) at the Open University simulates the extreme shock temperatures and pressures experienced during hypervelocity impact processing, vertically and horizontally and any angle in between.

Dr Zoe Emerland rotating the AALGG between horizontal and vertical orientation to demonstrate vertical momentum transfer experiments in preparation for missions DART and HERA

Facility Description

The All-Axis Light Gas Gun is a two-stage light gas gun, capable of firing 50 μm - 4 mm projectiles (spheres, cylinders or buckshot powders) at velocities up to ~6.0 km/s. Its unique capability of rotating between horizontal and vertical allows for the flexible option of two different target chambers.

The small target chamber can accommodate targets up to ~19 cm in radial diameter, for impacts horizontally, vertically, and intermediate angles by tilting the target.
The larger target chamber, for vertical firing only, can accommodate targets up to ~80 cm in diameter, along with supporting fixtures and equipment, ideal for testing whole systems or spacecraft assembly.

Instrumentation includes:

Projectile time of flight systems for velocity measurement

High Speed Camera frames showing a projectile impacting a surface and generating an ejecta cloud out of the back of the target — High Speed Camera frames of a 2 mm stainless steel projectile impacting a target at 3.5 km/s

High-speed cameras (Photron & Phantom) for recording projectile flight or impact processing
CAVILUX HF 640 Laser system for optimising schlieren and shadowgraphy and imaging impact flashes
High-speed pyrometer.
Head-space gas sampling.
Portholes for target viewing.
Feedthroughs for target cryogenic cooling, heating, electronic connections (e.g., BNC and DB), and any others desirable by the client.

The gun range is pumped down to ~0.2 mbar prior to firing to achieve the highest velocities, although firing at higher atmospheric pressures is possible.

The number of shots we can complete in one working day (and therefore the cost of using the instrument) will vary depending on the velocity, inclination of firing, projectile size and composition, specific firing conditions, misfires, pre- and post-firing cleaning and target preparation and processing.

If you have any queries about costings, testing conditions or capabilities, do not hesitate to Contact us!

Specification summary

Projectile Diameter	50 µm - 4 mm
Projectile Velocity	300 m/s - 6 km/s
Target Diameter	up to ~80 cm

Potential uses and applications of our powerful tool include:

Testing spacecraft, satellite and aerospace components and payload qualification - assessing vulnerabilities, durability and functionality
Whipple shield testing
Impact sensor detection and analysis
Projectile survival, deformation and recovery
Space debris ejecta generation

Impact cratering research - ground truthing and validation of numerical hydrocode models, fieldwork and remote sensing observations
Investigating planetary compositions - how can impacts inform about the composition and structure of a planetary surface and subsurfaces, and layering?
Chemical and physical modification of planetary surfaces from shock processing - using real or analogue materials
Regolith generation and ejection & space weathering - vertical impacts into loosely consolidated regolith-like materials
Meteorite studies - shock processing validation
Icy moon studies - investigate how impacts vary on icy surfaces, such as the icy moons of Jupiter and Saturn.

Momentum transfer studies for asteroid re-direction - for missions such as DART and HERA

Lithopanspermia - investigate how biosignatures can be transported between planetary bodies, e.g., Earth to the Moon; Mars to Phobos; Earth to Mars etc.
Generation of conditions conducive to the development of life
Modification of biosignatures by shock processing

Thermal & structural responses to extreme stress - impact-induced phase transitions and fracture mechanics - ices, glasses, metals, composites, layered materials, liquids, gels, natural and synthetic fibres - you name it, we can probably test it!
Armour, shielding and penetration testing
Spallation studies
Product development - design of new materials for extreme environments
Shock wave propogation
Equation of state studies