Rubens tube at Penn State AstroFest July 2019
Penn State AstroFest which is held annually during Central Pennsylvania of the Arts
A Rubens tube, also known as a standing wave flame tube, or simply flame tube, is a physics apparatus for demonstrating acoustic standing waves in a tube. Invented by German physicist Heinrich Rubens in 1905, it graphically shows the relationship between sound waves and sound pressure, as a primitive oscilloscope. Today, it is used only occasionally, typically as a demonstration in physics education.
Since 1999, Penn State Astronomy students, faculty, and friends have been inviting the public to Davey Lab at the Penn State University Park campus for AstroFest, a four night festival of Astronomy held concurrently with the Central Pennsylvania Festival of the Arts. AstroFest features many exciting activities, talks, and presentations, including stargazing through the telescopes on the roof of Davey Lab.