Kiruna, Northern Sweden. On Sunday, November 22^nd, 2009 the unmanned sounding rocket TEXUS-46 was launched from the Esrange launch site at 12:15 local time (11.15 UTC). Various experiments under ESA and/or DLR contract were on board the 12.4 meter and 2,652 kg rocket (payload mass: 373 kg).

Kayser-Threde, a subsidiary of OHB Technology, was, together with DLR Moraba, responsible for the Service Module with telemetry, telecommand, TV image transmission, payload motion control, micro-g measurement and the payload salvaging system. In addition, Kayser-Threde provided on-the-spot campaign support and was in charge of payload integration.

The experiments: “Chill-cooling for the electromagnetic levitator in relation to the continuous solidification of steel melt”, “High-precision determination of thermo-physical property data of liquid metals for modelling industrial solidification processes” and “Measurement of surface tension and viscosity on a PdSi (palladium silicon) sample” were performed in the rocket’s German-European EML-3 Module (electromagnetic levitator) under German supervision. TEXUS is also considered amongst international researchers to be a recognized research platform: In the JCM (Japanese combustion Module) Japanese scientists in cooperation with a German institute examined the “flame propagation process in a droplet array” with the aid of various cameras.

The parabolic flight brought the sounding rocket to an altitude of 252,3 km. Weightlessness prevailed on board for 388 seconds (i.e. 6 minutes and 28 seconds). The payload’s whole flight phase could be tracked by a GPS receiver relating to the service system. TEXUS-46 returned to earth on a parachute and was quickly located with the aid of GPS and ground infrastructure and then salvaged by helicopter. First evaluations of the systems and the experiment data confirmed complete mission success.

Within the frame of the scientific program TEXUS [German acronym meaning technological experiments under weightlessness (µg)], scientists conduct biological, physical and material science experiments under µg conditions. The program was funded since 1976 by the BMBF (German Federal Ministry of Education and Research) until, several years ago, the BMWI (Federal Ministry of Economics and Technology) or, rather, the Space Agency of the German Aerospace Center (DLR) took over.

The Swedish Space Corporation is the launch site operator at Esrange. Sounding Rockets like TEXUS (with approximately 6 minutes µg) and MAXUS (12 minutes µg) enable research under weightlessness at comparatively favorable conditions. Since double campaigns add to cost-effectiveness, the launch of TEXUS-47 is under preparation and lift-off planned for November 25^th.

Apart from sounding rockets, scientists and engineers can use the following platforms to carry out or test their experiments under µg conditions: Experiments can be carried out in a drop tower (4 sec µg), in a catapult (8 sec. µg, parabolic flight) or on board of a parabolic flight aircraft (with 25 sec. µg per parabola). More complex experiments can thus be tested step by step and modified as need arises. The Kayser-Threde platform, KAP, to be launched with a carrier of the European Launcher Family (for more information please refer to www.kayser-threde.com/KAP) can subject experiments to weightlessness for several days. Russian re-entry capsules of the type FOTON orbit the Earth for a fortnight. Long-term experiments with durations of several months can be performed on board of Technology Experiment Carriers like the German TET-1 satellite (keyword: On-Orbit Verification).Kayser-Threde was awarded the prime contract by DLR. 11 payloads will be verified in space for at least 12 months. TET-1’s launch is scheduled for the end of 2010. On the International Space Station long-term experiments can be carried out and supervised directly by a human being.