The infrasound array I27DE is located about 3 km southwest of the observatory. It is operated on behalf of the Federal Institute for Geosciences and Natural Resources (BGR) and the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO). It is an array with nine microbarographs which are arranged in a helical shape and covering an area of approx. 2.5 km diameter. The major task of the array is to contribute to control the compliance with the test-ban-treaty. I27DE is one of 321 worldwide operating monitoring CTBTO stations (IMS International Monitoring System), which are recording besides infrasound also seismic and hydroacoustic signals and radionuclide tracers. There are 60 infrasound stations operating worldwide, and 4 of them located in Antarctica. Data is transferred continuously to NM-III via W-LAN and further on to AWI Bremerhaven, BGR Hanover and CTBT Vienna. During winter all requested service works are done by the geophysicists of the overwintering team. Annual maintenance works during the summer season are done by the BGR staff together with AWI technicians. Detailed information from this observatory can be found on the website of BGR.