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In-situ dust mass distribution measurements from Giotto encounter with comet P/Halley.

Perry, Christopher, H. (1990) In-situ dust mass distribution measurements from Giotto encounter with comet P/Halley. Doctor of Philosophy (PhD) thesis, University of Kent. (doi:10.22024/UniKent/01.02.94581) (KAR id:94581)


On the night of the 13/14th of March 1986 the European Space Agency's Giotto spacecraft passed within 600km of the nucleus of comet P/Halley. On board the spacecraft was an impressive array of experiments designed to study all aspects of the cometary coma and provide high resolution images of the nucleus. The principle experiment designed to measure the coma dust mass distribution was called the Dust Impact Detection System (DIDSY). The design operation and performance of this experiment are considered and details are provided of post-mission recalibration, including the development of a software simulation to aid in the interpretation of the returned data. The faulty operation of one of the DIDSY sensors resulted in the use of ) the front end channels of the Particulate Impact Analyser Experiment (PIA) to provide information on particles of mass 10*19kg < m < 10-15kg. The techniques used to extract the required information and calibrate the sensor using encounter data and the inter-relationship between different operating modes is described. The analysis of impacts which caused multiple detection by two or more of the DIDSY sensors is described and the results from these multi-sensor events used to extend the measured mass range up to 10_5kg. A mass distribution representative of the coma passed through by Giotto was constructed and this is combined with a simple model to obtain the dust production rate and dust to gas ratio.

Item Type: Thesis (Doctor of Philosophy (PhD))
DOI/Identification number: 10.22024/UniKent/01.02.94581
Additional information: This thesis has been digitised by EThOS, the British Library digitisation service, for purposes of preservation and dissemination. It was uploaded to KAR on 25 April 2022 in order to hold its content and record within University of Kent systems. It is available Open Access using a Creative Commons Attribution, Non-commercial, No Derivatives ( licence so that the thesis and its author, can benefit from opportunities for increased readership and citation. This was done in line with University of Kent policies ( If you feel that your rights are compromised by open access to this thesis, or if you would like more information about its availability, please contact us at and we will seriously consider your claim under the terms of our Take-Down Policy (
Uncontrolled keywords: Comet dust analysis
Subjects: Q Science > QB Astronomy
Divisions: Divisions > Division of Natural Sciences > Physics and Astronomy
SWORD Depositor: SWORD Copy
Depositing User: SWORD Copy
Date Deposited: 17 May 2023 11:23 UTC
Last Modified: 17 May 2023 11:33 UTC
Resource URI: (The current URI for this page, for reference purposes)

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