The REXUS/BEXUS Programme
For the past decade, the German (DLR) and Swedish (SNSA) space agencies have given the opportunity to university students to carry out scientific experiments on sounding rockets and balloons, the REXUS/BEXUS programme. This bilateral agreement has been made available to students from other European countries through a collaboration between the Swedish Space Agency and the European Space Agency (ESA)
Balloon EXperiments for University Students
The REXUS/BEXUS programme was created in 2007 thanks to the cooperation of DLR and SNSB (now SNSA). Today the programme allow students from Universities and higher education colleges across Europe to develop their own experiments on different research areas such as atmospheric research, fluid physics, magnetic field, materials science, radiations physics, astrophysics, biology and also on technology demonstrators.
Each year, two BEXUS balloons are launched from SSC, Esrange Space Center in northern Sweden.
Payloads are assembled on a medium-sized gondola (1.16 m x 1.16 m x 0.84 m). The total lifted-mass is approximately 300kg with payload weighing between 30 and 112kg (which means generally 4 student experiments per gondola). The balloon, a 35SF from Zodiac aerospace, is filled with helium gas.
The flight of the BEXUS is composed of several steps:
- The launch, the experimental payload housed in the gondola is held by a launch vehicle called HERCULES and is released when the balloon inflation is completed and the flight line lifted
- The ascent phase, the nominal ascent speed is 5m/s. This phase lasts approximately 1.5 hours depending on the final float altitude
- The float phase, the altitude is most of the time between 25-33 km and can last between 1-5 hours (depending on the float direction and wind speed)
- The descent phase (un-piloted descent). The gondola and flight line descend under a parachute
- The landing (around 8m/s)
- And the recovery of the payload