Radio spectroscopy and space science with VLBI radio telescopes for Solar System research

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dc.contributor Aalto-yliopisto fi
dc.contributor Aalto University en
dc.contributor.advisor Pogrebenko, Sergei, Doctor, the Joint Institute for VLBI ERIC, the Netherlands
dc.contributor.author Molera Calvés, Guifré
dc.date.accessioned 2012-08-06T06:51:26Z
dc.date.available 2012-08-06T06:51:26Z
dc.date.issued 2012
dc.identifier.isbn 978-952-60-4581-8 (electronic)
dc.identifier.isbn 978-952-60-4580-1 (printed)
dc.identifier.issn 1799-4942 (electronic)
dc.identifier.issn 1799-4934 (printed)
dc.identifier.issn 1799-4934 (ISSN-L)
dc.identifier.uri https://aaltodoc.aalto.fi/handle/123456789/4422
dc.description.abstract Only a tiny fraction of the universe has been studied even though the possibilities are unlimited given the current technologies, the resources and the time. To optimize the use of resources, the Metsähovi antenna and the existing VLBI processing hardware were exploited to study a broad variety of space phenomena. The research began with radio spectroscopy of the celestial bodies of our Solar System. Every object emits certain spectral signatures at several radio frequencies depending on its chemical molecules. Earth-based observations of the emitted radio spectral signal help to determine the composition of the structure and atmosphere of the planets. A unique method for processing the data captured by VLBI radio telescopes for radio spectroscopy purposes was developed during this work. Although the initial research focused on planetary bodies, it later shifted to the spacecraft motion. This new aim included studying ground support to planetary and deep-space mission spacecraft with VLBI radio telescopes, which opened up possibilities for collaboration between space agencies and radio astronomers. In addition, with VLBI phase-referencing, a high accuracy estimation of the spacecraft state vectors could be obtained. These new tools provide an opportunity for studying a broad variety of physical processes, including the dynamics of planetary atmospheres, geodynamical diagnostics of the interior of planets, fundamental physics effects of spacecraft motion and solar wind characterization. For instance, we organised a VLBI tracking session of Venus Express that involved 10 antennae and it estimated the spacecraft position with a precision of few hundred metres. The most interesting physical process for further investigation was the characterisation of the solar wind along the propagation path. The phase fluctuations on the signal allowed us to study essential parameters of the interplanetary scintillations, such as the phase scintillation index, bandwidth of scintillations or spectral broadening and their dependence on the solar elongation, distance to the target, celestial position of the spacecraft and radio telescopes. A scintillation and electron density model as a function of solar elongation was developed based on the data collected during two years. This model is powerful for improving the accurate determination of the spacecraft state vectors. en
dc.format.extent 216
dc.format.mimetype application/pdf
dc.language.iso en en
dc.publisher Aalto University en
dc.publisher Aalto-yliopisto fi
dc.relation.ispartofseries Aalto University publication series DOCTORAL DISSERTATIONS en
dc.relation.ispartofseries 42/2012
dc.subject.other Space technology en
dc.title Radio spectroscopy and space science with VLBI radio telescopes for Solar System research en
dc.type G4 Monografiaväitöskirja fi
dc.contributor.school Sähkötekniikan korkeakoulu fi
dc.contributor.school School of Electrical Engineering en
dc.contributor.department Radiotieteen ja -tekniikan laitos fi
dc.contributor.department Department of Radio Science and Engineering en
dc.subject.keyword Very Long Baseline Interferometry en
dc.subject.keyword spacecraft tracking en
dc.subject.keyword Doppler en
dc.subject.keyword radio spectroscopy en
dc.subject.keyword space science en
dc.subject.keyword interplanetary scintillation en
dc.identifier.urn URN:ISBN:978-952-60-4581-8
dc.type.dcmitype text en
dc.type.ontasot Doctoral dissertation (monograph) en
dc.type.ontasot Väitöskirja (monografia) fi
dc.contributor.supervisor Hallikainen, Martti, Prof.
dc.opn Mantovani, Franco, Doctor, Istituto di RadioAstronomia, Italy
dc.rev Wiik, Kaj, Doctor, Tuorla Observatory, University of Turku, Finland
dc.rev Whitney, Alan R., Doctor, MIT/Haystack radio observatory, USA
dc.date.defence 2012-04-27


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