Supersonic flight over land is generally prohibited because sonic booms created by shockwaves disturb people on the ground and can damage property. Armstrong innovators are working to solve this problem with a novel system for capturing images of shockwaves created by supersonic aircraft. The Background Oriented Schlieren Using Celestial Objects (BOSCO) technology uses a celestial object, such as the Sun, as a background to secure unique, measurable shockwave images of full-scale aircraft. The patented image-processing technology captures hundreds of observations with each shockwave, benefitting NASA engineers in their efforts to develop a supersonic aircraft that will produce a soft “thump” in place of a disruptive sonic boom.

The Schlieren image dramatically displays measurable shockwave images of a supersonic aircraft.

The system visualizes air density gradients generated by air compressing as it flows around an object. Researchers first obtain a celestial background image and then collect a series of images of an object in supersonic flow in front of the celestial object. The density change in the air refracts the light, shifting the background as compared to the undisturbed background image. The amount of movement corresponds directly to density gradients in the airflow. Using computer algorithms to analyze the images, resultant images essentially show the distortions caused by the aerodynamic flow of shockwaves passing between the camera and the celestial background.

Schlieren photography has been used for years in wind tunnels, where the environment is controlled. BOSCO enables its use in the real atmosphere with real propulsion systems. Studying life-sized aircraft flying through Earth’s atmosphere provides better results than modeling and can help engineers design better and quieter supersonic airplanes.

In addition to studying shockwaves for aircraft, the Schlieren techniques have the potential to aid the understanding of a variety of flow phenomena and air density changes such as investigating airflows around tall buildings and the tips of wind turbines and helicopter blades.

NASA is actively seeking licensees to commercialize this technology. Please contact the NASA Armstrong Technology Transfer Office at 661-276-3368 or This email address is being protected from spambots. You need JavaScript enabled to view it. to initiate licensing discussions. Follow this link here  for more information.