Published: 17. March 2015 by: Trond Abrahamsen

WADIS-2 rocket launched March 5, 2015 at 2:44 CET

Original article by DLR: http://www.dlr.de/dlr/desktopdefault.aspx/tabid-10081/151_read-12971/#/gallery/18849

The atmosphere is a highly complex system, with interacting in effects such as sunlight, changing gas compositions, dust, ice crystals and electrical charge. They influence weather patterns and climate development. Specifically, the density changes in the Middle atmosphere is examined by the WADIS project (wave propagation and dissipation in the middle atmosphere) of the Leibniz-Institute of Atmospheric Physics (IAP) in Kühlungsborn with the support of the German Aerospace Center (DLR). On March 5, 2015 at 2:44 Central European Time, the sounding rocket WADIS-2 launched from Andøya Space Center with nine experiments on board into the night sky above Norway. In addition, 13 small, simple “weather rockets” named Loki-Dart, measures the pressure and temperature in the days before and after WADIS, thereby determining a larger weather environment.

The 1550 kg heavy WADIS-2 rocket reached an altitude of around 126 km. During the flight the sensors detected air pressure, temperature, electrical charges as well as density changes in the atmosphere. These changes in air density, so-called gravity waves can be measured in terms of temperature, pressure and wind fluctuations. They occur, for example, where wind currents near ground pass an obstacle, such as a mountain range, and these disorders continue to about 80 km altitude. The phenomenon of gravity waves is known, but have not yet been thoroughly explored in a wide range. However, this is an important prerequisite to improve climate models in the future.

Five experiments on board WADIS-2 were German. Three of them were from scientists at the Leibniz-Institute of Atmospheric Physics: the CONE sensors (Combined Measurement of Neutrals and Electrons) for measurement of density fluctuations, a particle sensor for the determination of aerosols and a so-called falling ball (Active Falling Sphere). Falling balls were used earlier in meteorology. They were dropped at a certain height, and radar measurements from the ground determined the air density, temperature and horizontal wind speeds. These 25 centimeter and three-pound falling balls has their own measuring instruments on board, which is why they are referred to as “active”. These are 3D Accelerometers, gyros, GPS receivers and radio electronics. The ball is located between the rocket motor and the payload, and is ejected after the separation of the engine.

After about ten minutes of flight the payload unit watered in the North Atlantic, about 80 miles off the coast of Norway. There it was taken on board a salvage vessel and transported back to Andøya for further evaluation of the experiments. Already, half a year ago, on 28 June 2013, the predecessor rocket WADIS-1 was launched. That mission took place in the transitional period between spring to summer, while WADIS-2 started in the winter. From a scientific point of view, this difference is very important because then the atmosphere is in a different state. It is very easy, based these ongoing processes, to conclude on scientific grounds. With the WADIS project, the ECOMA research program was continued from September 2006 to December 2010 with the launch of nine sounding rockets.

The WADIS project is under the scientific leadership of the Leibniz Institute of Atmospheric Physics. Other partners include the University of Stuttgart and the Ludwig-Maximilians University in Munich. The instruments were made part of the Schwetzingen company from Hoerner & Sulger Gmbh, the “Active Falling Sphere” was developed by the IAP, the Argus Electronik GmbH and the Institute of Electrical Engineering of the University of Rostock. The Mobile Rocket Base of the German Aerospace Center (DLR-MORABA) in Oberpfaffenhofen was responsible for the implementation of the launch campaign. The project is funded by the DLR Space Administration with support from the Federal Ministry for Economic Affairs and Energy (BMWi).