Bioscience experiments in the German Spacelab mission D-1: introduction and summary.

The German Spacelab mission D-l was performed from 30 October through 6 November 1985. Payload operation in orbit was managed by DFVLR for the Federal Ministry of Research and Technology. The scientific program of the mission placed emphasis on microgravity research. In bioscience, the role of gravity in vital functions of biological systems was investigated, such as intracellular and intercellular interactions, developmental processes as well as regulation and adaptation in highly organized systems including human beings. In addition, the biological significance of cosmic radiation or altered zeitgeber within the complex matrix of all relevant spaceflight components were studied. Most of the experiments were accommodated in the following three payload elements: The Bioscience Experiment Package, and the ESA facilities Vestibular Sled and BIORACK. The information gained from the individual experiments will be compiled to help answer pending questions of space bioscience.     

The NOAA Real-Time Solar-Wind (RTSW) System using ACE Data

The Advanced Composition Explorer (ACE) RTSW system is continuously monitoring the solar wind and produces warnings of impending major geomagnetic activity, up to one hour in advance. Warnings and alerts issued by NOAA allow those with systems sensitive to such activity to take preventative action. The RTSW system gathers solar wind and energetic particle data at high time resolution from four ACE instruments (MAG, SWEPAM, EPAM, and SIS), packs the data into a low-rate bit stream, and broadcasts the data continuously. NASA sends real-time data to NOAA each day when downloading science data. With a combination of dedicated ground stations (CRL in Japan and RAL in Great Britain), and time on existing ground tracking networks (NASA's DSN and the USAF's AFSCN), the RTSW system can receive data 24 hours per day throughout the year. The raw data are immediately sent from the ground station to the Space Environment Center in Boulder, Colorado, processed, and then delivered to its Space Weather Operations center where they are used in daily operations; the data are also delivered to the CRL Regional Warning Center at Hiraiso, Japan, to the USAF 55th Space Weather Squadron, and placed on the World Wide Web. The data are downloaded, processed and dispersed within 5 min from the time they leave ACE. The RTSW system also uses the low-energy energetic particles to warn of approaching interplanetary shocks, and to help monitor the flux of high-energy particles that can produce radiation damage in satellite systems. This revised version was published online in June 2006 with corrections to the Cover Date.     

Mass transport in the near vicinity of solidification fronts under conditions of microgravity

Cellular solidification has been known and discussed since a long time. The appearance of cellular and dendritic microstructure closely resembles Benard cells known from fluid physics. Similar generation mechanismus may possibly be assumed. Both g-dependent and g-independent convective phenomena may probably be linked to the occurrence of instabilities at solidification fronts. It is to be expected that normal freezing of model alloys (advantageously such with no volume change at the freezing point) in a defined temperature gradient (gradient furnace) and quenching them may help to quantity g-influence on solidification.