Browsing by Author "Pogrebenko, S. V."
Now showing 1 - 2 of 2
- Results Per Page
- Sort Options
- A monitoring campaign (2013-2020) of ESA's Mars Express to study interplanetary plasma scintillation
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2023-04-12) Kummamuru, P.; Molera Calvés, G.; Cimò, G.; Pogrebenko, S. V.; Bocanegra-Bahamón, T. M.; Duev, D. A.; Md Said, M. D.; Edwards, J.; Ma, M.; Quick, J.; Neidhardt, A.; De Vicente, P.; Haas, R.; Kallunki, J.; MacCaferri, G.; Colucci, G.; Yang, W. J.; Hao, L. F.; Weston, S.; Kharinov, M. A.; Mikhailov, A. G.; Jung, T.The radio signal transmitted by the Mars Express (MEX) spacecraft was observed regularly between the years 2013-2020 at X-band (8.42 GHz) using the European Very Long Baseline Interferometry (EVN) network and University of Tasmania's telescopes. We present a method to describe the solar wind parameters by quantifying the effects of plasma on our radio signal. In doing so, we identify all the uncompensated effects on the radio signal and see which coronal processes drive them. From a technical standpoint, quantifying the effect of the plasma on the radio signal helps phase referencing for precision spacecraft tracking. The phase fluctuation of the signal was determined for Mars' orbit for solar elongation angles from 0 to 180 deg. The calculated phase residuals allow determination of the phase power spectrum. The total electron content of the solar plasma along the line of sight is calculated by removing effects from mechanical and ionospheric noises. The spectral index was determined as which is in agreement with Kolmogorov's turbulence. The theoretical models are consistent with observations at lower solar elongations however at higher solar elongation ($ ]]>160 deg) we see the observed values to be higher. This can be caused when the uplink and downlink signals are positively correlated as a result of passing through identical plasma sheets. - Planetary Radio Interferometry and Doppler Experiment (PRIDE) technique
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä(2016-09-01) Duev, D. A.; Pogrebenko, S. V.; Cimò, G.; Molera Calvés, G.; Bocanegra Bahamón, T. M.; Gurvits, L. I.; Kettenis, M. M.; Kania, J.; Tudose, V.; Rosenblatt, P.; Marty, J. C.; Lainey, V.; De Vicente, P.; Quick, J.; Nickola, M.; Neidhardt, A.; Kronschnabl, G.; Ploetz, C.; Haas, R.; Lindqvist, Michael; Orlati, A.; Ipatov, A. V.; Kharinov, M. A.; Mikhailov, A. G.; Lovell, J. E J; McCallum, J. N.; Stevens, J.; Gulyaev, S. A.; Natush, T.; Weston, S.; Wang, W. H.; Xia, B.; Yang, W. J.; Hao, L. F.; Kallunki, J.; Witasse, O.Context. The closest ever fly-by of the Martian moon Phobos, performed by the European Space Agency's Mars Express spacecraft, gives a unique opportunity to sharpen and test the Planetary Radio Interferometry and Doppler Experiments (PRIDE) technique in the interest of studying planet-satellite systems. Aims. The aim of this work is to demonstrate a technique of providing high precision positional and Doppler measurements of planetary spacecraft using the Mars Express spacecraft. The technique will be used in the framework of Planetary Radio Interferometry and Doppler Experiments in various planetary missions, in particular in fly-by mode. Methods. We advanced a novel approach to spacecraft data processing using the techniques of Doppler and phase-referenced very long baseline interferometry spacecraft tracking. Results. We achieved, on average, mHz precision (30 μm/s at a 10 s integration time) for radial three-way Doppler estimates and sub-nanoradian precision for lateral position measurements, which in a linear measure (at a distance of 1.4 AU) corresponds to ∼50 m.