On 7 June 1972 the third , Jovian satellite Ganymede occulted the eighth-magnitude star SAO 186800. Successful photoelectric observations obtained at Lembang, Java (Indonesia), and Kavalur, India, show nonabrupt immersions and emersions, indicating the presence of an atmosphere whose surface pressure is greater than about 10(-3) millibar. By fitting the two occultation durations as chords to a ...

First results from the GPS radio occultation experiment aboard the German CHAMP satellite are presented. The agreement between observed temperature profiles in the upper troposphere and the lower stratosphere and temperature profiles obtained from meteorological analyses is found to be below 1 K. The data processing and analysis system (operated by GeoForschungsZentrum Potsdam) has been success...

The Global Ozone Monitoring by Occultation of Stars instrument (GOMOS) will be launched on board ESA’s Envisat satellite in late 2001. GOMOS will measure ozone and trace gases in the atmosphere by detecting the absorption of star light in UV, visible and infrared wavelengths. GOMOS will deliver ozone and other trace gas profiles at altitudes 15-90 km with a good vertical resolution and with a g...

We report a planned search technique for Gamma-Ray Bursts too weak to trigger the on-board threshold. The technique is to search residuals from a physically based background model used for analysis of point sources by the Earth occultation method. Searching residuals (as opposed to raw data) minimizes false triggers from occultation edges and many other effects which lead to a rapid variation i...

Recent work has shown that the retrieval of stratospheric aerosol vertical profiles is possible using limb scattered sunlight measurements at optical wavelengths. The aerosol number density profile is retrieved for an assumed particle size distribution and composition. This result can be used to derive the extinction at the measured wavelength. However, large systematic error can result from th...

Solar occultation with SCIAMACHY: algorithm description and first validation J. Meyer, A. Bracher, A. Rozanov, A. C. Schlesier, H. Bovensmann, and J. P. Burrows Institute of Environmental Physics, University of Bremen, Germany Received: 20 September 2004 – Accepted: 25 October 2004 – Published: 10 January 2005 Correspondence to: J. Meyer ([email protected]) © 2005 Author(s). This ...

The effective temperature of Saturn from 30øS to 10øN is 96.5 + 2.5 K. This value is 1.9 K higher than our preliminary estimate (Ingersoll et al., 1980). The atmospheric mole fraction of H2 relative to H2 + He is 90 + 3%. This value is derived by comparing infrared and radio occultation data (Kliore et al., this issue) for the same latitude. The high value of the effective temperature suggests ...

This paper presents the application of Neural Networks for the spatial and temporal modeling of (critical frequency) foF2 data over Europe. foF2 is the most important parameter in describing the electron density profile of the ionosphere since it represents the critical point of maximum electron density in the profile and therefore can be used to drive empirical models of electron density which...

Generalization of radio holographic method for 3-dimensional case is presented. Application of this method to analysis of radio occultation data gives high vertical resolution and accuracy in estimating physical parameters of the ionosphere and atmosphere and allows recovering vertical temperature gradients and wave structures in the atmosphere and in the ionosphere.