Last week, ESA Academy selected a team for the 2019 Drop Your Thesis! programme. Team Bubbles, comprising four students from the International Space University in France, applied for the programme two months earlier, with an experiment that aims to learn more about the fundamental physics of sonoluminescence: i.e. the emission of short bursts of light from imploding bubbles in a liquid when excited by sound. Even though a great deal of experimental and theoretical work has already been done in this field, the source and mechanisms underlying the light flash remain elusive to date.
It is expected that the light bursts visible during the collapse are due to high temperatures and pressures, also called sonofusion. In the absence of gravity, the bubble stability is expected to improve, allowing higher pressures, larger bubble sizes and therefore increased light intensity. Team Bubbles therefore desires to build on this hypothesis, by examining improved observation of sonoluminescence in microgravity.
As the phenomenon of Team Bubble’s study is very dependent on the environment and the stability of the experiment, the high quality of microgravity conditions (10-6g) ZARM’s drop tower in Bremen fits their experiment perfectly. The drop tower reaches a height of 146 meters, housing a 120 meter high tube from which the air can be removed. The students will make use of the drop mode, meaning that they will release a capsule from the top of the inner tube, which gives them 4.67 seconds of microgravity. While dropping the capsule, a bubble will be trapped in an acoustic field filled with degassed water.
The students will be supported throughout the programme by experts of ESA Academy and ZARM. A member of the European Low Gravity Research Association (ELGRA) will also be on hand to provide advice and expertise in gravity-related research. The team will meet with ESA Education, ZARM experts and many other teams participating in the 2019 hands-on programmes of ESA Academy in January at ESA Academy’s Galaxia Training and Learning Facilities in Belgium for a week-long training session on how to tackle such a big project.
The actual campaign is scheduled to take place during two weeks, from 21st of October to the 1st of November 2019 at the ZARM Drop Tower. During the first week, the team will perform the integration of the experiment with the ZARM drop capsule; during the second week, a maximum of five drops will be granted.
This opportunity complements other microgravity research opportunities offered by ESA Education Office, such as 'Fly Your Thesis!’ and the new ‘Orbit Your Thesis!’. For further information on these programmes, please refer to the ESA Education website.