Search

This paper presents EMC measurements from the ‘Planetary ion camera’ (PICAM) instrument, a part of the SERENA instrument suite aboard BepiColombo, an ESA/JAXA two spacecraft mission to the Hermean system. After a short description of the scientific goals and PICAM characteristics, we focus on results obtained by the QM and FM. For the electronics boards and the ion optics conducted emission and susceptibility are of particular interest in order to meet the instrument requirements. Relevant are interferences on the gates or high voltage electrodes, i.e. finally disturbances of the ion trajectories, they have to be avoided and considered in the design improvement of the models.

In this paper we describe the Graz seismo-electromagnetic very low frequency (VLF) facility, as part of the European VLF receiver network, together with the scientific objectives and results from two years operation. After a brief technical summary of the present system – with heritage from a predecessor facility – i.e. hardware, software, operational modes and environmental influences, we discuss results from statistical data and scientific events related to terrestrial VLF propagation over Europe.

International audience; We analyse the flux density variation associated to low frequency (LF) broadcasting transmitters observed by the ICE electric field experiment onboard DEMETER micro-satellite, observed from 01st Jan. to 09th Dec. 2010. We select five stations localised around the Mediterranean and the Black seas: Tipaza (252 kHz, 02°28’E, 36°33’N, Algeria), Roumoules (216 kHz, 06°08’E, 43°47’N, Monte Carlo), Polatli (180 kHz, 32°25’E, 39°45’N, Turkey), Nadour (171 kHz, 02°55’W, 35°02’N, Morocco) and Brasov (153 kHz, 25°36’E,45°40’, Romania). The detection of the LF transmitter signals by DEMETER micro-satellite is found to depend on the radiated power, the emitted frequency, and the orbit paths with regard to the location of the stations. This leads us to characterise the reception condition of the LF signals and to define time intervals where the detection probability is high. We show that LF signal are regularly recorded, each 12 days, when the satellite is above the broadcasting station. The signal intensity levels are principally significant during the solar activity. Hence we find that the solar and the geomagnetic activities are slightly correlated to the maxima of LF signal as recorded by DEMETER. Also we note a drop of the intensity level several days before the occurrence of earthquakes in/around the Mediterranean and Black seas.

In this paper we present results obtained from more than two years continuous very low frequency (VLF) measurements between a network of VLF transmitters and receivers. The focus is on VLF amplitude and phase variations in the Earth lithosphere-ionosphere cavity with the scientific objective to characterise long term trends possibly related to planetary waves and climatological factors. After considering the nominal diurnal and seasonal behaviour of the individual paths in the VLF waveguide, we distinguish between natural and artifical disturbances on different temporal and spatial scales. We conclude that it is too early to speak of a clear trend, but VLF investigations together with complementary measurements can be a useful tool in long term environmental and climatological studies on medium spatial scales.

We investigate the combined use of acoustic, radio frequency and optical links for communication and scientific purposes for possible upcoming planetary missions, e.g., the proposed TandEM mission to the Saturnian moons Enceladus and Titan in the frame of ESApsilas Cosmic Vision 2015-2025 call. Based on experience with balloon flights and in-situ measurements in the venusian and terrestrial atmospheres and planetary probes at Jupiter, Mars and Titan, the major emphasis is on communication in planetary atmospheres.