The solar cosmic ray ground-level enhancements on 20 January 2005 and 13 December 2006

Close to the current solar activity minimum, two large solar cosmic ray ground-level enhancements (GLE) were recorded by the worldwide network of neutron monitors (NM). The enormous GLE on 20 January 2005 is the largest increase observed since the famous GLE in 1956, and the solar cosmic-ray event recorded on 13 December 2006 is among the largest in solar cycle 23. From the recordings of the NMs during the two GLEs, we determined the characteristics of the solar particle flux near Earth.     

German rockets in africa: The explosive heritage of peenemunde

This historical paper reviews the technical development and the political impact of two “intelligence affairs” with German rocketry in African countries: 1. the Nasser missiles and space projects in Egypt during the 1960s; 2. the private OTRAG venture in Zaire and Libya during the 1970s.