A dataset provided by the European Space Agency

Mission GIOTTO
URL ftp://npsa01.esac.esa.int/pub/mirror/GIOTTO/JPA/GIO-C-JPA-4-DDR-HALLEY-MERGE-V1.0
DOI https://doi.org/10.5270/esa-ooy7vg9
Abstract The GIO-C-JPA-4-DDR-HALLEY-MERGE-V1.0 data set contains the calibrated data of the Johnstone-Propulsion Analyser instrument on board of the GIOTTO spacecraft of the European Space Agency. The data were obtained during the GIOTTO flyby on comet Halley in March 1986
Description Data Set Overview = This dataset contains results from the Implanted Ion Sensor (IIS) 4DH mode and the Fast Ion Sensor SW and HAR modes of the Three- Dimensional Particle Analyzer (JPA) experiment on the GIOTTO spacecraft for the mission to comet Halley. The results of the Fast Ion Sensor (FIS - inbound) and IIS (outbound) have been merged with results from other Giotto instruments. In the first submitted table, magnetometer measurements are included. Values are given for protons. JPA FIS data are from two sources: - up to March 13, 19:24:55 SCET, data are from the solar wind mode at 8 seconds time resolution. The moments are derived from data in a 45 x 45 degree field of view, centered on the nominal solar wind direction. There is continuous coverage in energy and angle. The peak remains within this reduced field of view. - March 13, 19:24:55 to 22:38:17 SCET, data are from the HAR mode at 24 second time resolution. This mode has an angular field of view accepting ions from all directions except a 20 deg cone in the ram direction. Energy-angle coverage is not contiguous in this mode so an assumption is made to boost the counts in each bin to make the distribution appear contiguous. The peak of the solar wind flux alternates between the last two 26 deg bins during this period. Moments are calculated for the regions of space sampled by the detector, i.e. up to the 20 deg ram cone, with no assumption to increase the range beyond this. The following assumptions hold: FIS is an electrostatic analyzer and so cannot distinguish mass - except in the solar wind mode where the protons and alpha particles are cold enough that they separate in energy/charge; in HAR mode the moment is over the full FIS energy range so includes anything (all protons). The temperature profile from solar winds to HAR mode is not continuous due to the different bin sizes involved, so the sudden temperature jump at 19:24:55 should not...
Instrument JPA
Temporal Coverage 1986-03-12T06:09:30.000Z/1986-03-15T02:31:28.108Z
Version V1.0
Mission Description Mission Overview In 1978,ESA was invited by NASA to plan a joint mission consisting of a comet Halley fly-by in November 1985 and a rendezvous with comet Tempel 2 in 1988. The mission comprised an American main spacecraft which would carry a European probe. The main spacecraft, with its array of sophisticated cameras and experiments, would complete a fly-by of comet Halley at a safe distance. Shortly before fly-by, the probe would be released towards the nucleus to make detailed in-situ observations in the innermost coma. In January 1980, however, it became clear that financial support for the Halley Fly-by/Tempel 2 Rendezvous mission could not be secured in the USA. By that time the interest of European scientists had built up such momentum that ESA considered the possibility of a purely European mission. The support for a fly-by mission was strong in Europe and went far beyond the small section of scientists specialised in cometary research. A fly-by of comet Halley was suggested to ESA by the scientific community in February 1980. Rather than having the American spacecraft deliver the probe to the comet as in the earlier concept, the Europeans proposed that the capabilities of the small probe be increased by building an independent, self-sufficient spacecraft to be launched using the European Ariane rocket. The limited time available for development and the small financial resources made it advisable to use a spin-stabilised spacecraft derived from the European Earth orbiting spacecraft Geos. This proposal was studied by ESA in the first half of 1980. The European mission to comet Halley was named Giotto after the Italian painter Giotto di Bondone who depicted comet Halley as the `Star of Bethlehem' in one of his frescoes in the Scrovegni chapel in Padua in 1304. The Giotto mission was finally approved as ESA's first interplanetary mission on 7 July 1980. An Announcement of Opportunity was issued ...
Date Published 2004-03-26
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, 2004-03-26, GIO-C-JPA-4-DDR-HALLEY-MERGE, V1.0. https://doi.org/10.5270/esa-ooy7vg9