A team of students from the Lucerne University of Applied Sciences and Arts intends to fly within the REXUS program a biological experiment aboard a sounding rocket. The team has proposed to investigate the effect of microgravity (weightlessness) on mechanosensitive ion channels using frog eggs.
REXUS is for Rocket Experiments for University Students and is a training program of the German Aerospace Center (DLR) and the Swedish National Space Board (SNSB). Student teams can apply for a place on one of the two sounding rockets, which are launched annually. Since Sweden open their share of all Member States of the European Space Agency (ESA), also Swiss students are allowed to participate in this competition. The teams have to compete in a two-stage selection procedure to get a ticket.
- Spring 2014: The students Mathias Hosennen and Yves Métry develop an initial concept for the flight hardware as part of their undergraduate thesis.
- Fall 2014: The current undergraduate students will be let into the professional world and three new students, Christoph Hardegger, Mario Felder (Bachelor) and Tobias Plüss (Master) complete the team. The experiment will be submitted to REXUS program.
- December 2014: The Lucerne proposal is included in the shortlist. The team can therefore introduce the experiment at the European Space Technology Headquarters (ESTEC) in Noordwijk (Netherlands). It is possible to convince the committee of experts. The Space flight ticket is safe for the student project.
- January 2015:The first issue of the Student Experiment Documentation (SED) has to be handed in.
- February 2015: During the Student Training Week at the DLR in Oberpfaffenhofen, Germany, the team goes through the Preliminary Design Review (PDR). In numerous lectures and discussions with the expert many technological and operational aspect concerning a sounding rocket experiment could be discussed.
The experiment will take place on a rocket type Improved Orion. The rocket is modular so that multiple experiments can be placed on the same rocket. In a roughly 10-minute flight, the rocket rises up to an altitude of around 82 km with an acceleration of twenty times the value of gravity. The rocket finally lands back on Earth with a parachute.
The experiment-module is built with three levels:
- On the top, the measurement and control electronics are housed, which automatically controls the experiment.
- Below this are two drawers so called late-access modules. On each module three measuring chambers are mounted, in which the actual experiment takes place. In each measuring chamber a frog’s egg (oocyte) is placed. During the flight, the ion flux across the cell Membrane is measured.
- At the bottom containers for the liquids are accommodated.
Because the experiment uses living frog eggs, they should be charged into rocket as late as possible. The late-access modules make it possible.
Gravity is one of the four fundamental forces. Since life evolved under gravity, many organisms have acquired organs to use gravity for orientation.
With the onset of manned space flight, it became clear that microgravity (or weightlessness) has sever effects on the human organism. Interestingly the microgravity does not only affect whole organisms and organs, but also single cells.
Until now it is not entirely clear, how cells can detect external forces. Besides other proteins, mechanosensitive ion channels are thought to be one of the key players. Therefore we would like to study the behavior of such ion channels under microgravity condition.
Among the many physiological consequences of manned space flight, muscle atrophy is certainly the most obvious and one of the most detrimental to the human condition. The currently applied countermeasures, however, can only partially alleviate the muscle wasting associated with the mechanical unloading because of reduced gravitational force. Since bedridden patients and elderly suffer from similar symptoms, space is a good laboratory to study mechanobiological processes.