A dataset provided by the European Space Agency

Name GIO-C-PIA-3-RDR-HALLEY
Mission GIOTTO
URL ftp://npsa01.esac.esa.int/pub/mirror/GIOTTO/PIA/GIO-C-PIA-3-RDR-HALLEY-V1.0
DOI https://doi.org/10.5270/esa-dgsk768
Abstract The GIO-C-PIA-3-RDR-HALLEY-1.0 dataset contains the dust mass spectra of comet Halley obtained by the Particle Impact Analyser Dust Mass Spectra on board of the GIOTTO spacecraft of the European Space Agency
Description Data Set Overview = The PIA data was acquired in four modes of data compression, termed mode 0 (the least compressed), and modes 1, 2, and 3, each with increasing degrees of compression. With each spectrum are a PIA assigned sequence number and event numbers, a unique ID-number, instrument settings, and the relative approach time. The PIA time is a 16-bit counter that starts with zero after switch-on. As the Spacecraft Time Signal (STS) is used to reset the internal PIA time counter, the TIM highest possible value is 48960 counts. STS-pulses are given after the transimssion of 256 formats. This results for format F1/F2 and high bitrate (46080 bps) in 5802.67 s. (= 256 formats * 64 frames * 2040 bytes * 8 bit/byte/46080 bps) The time resolution is DTIM = 1/ (138240 HZ /2**14 ) = 0.1185 s. Each STS defines the time for an event with TIM = 0. Therefore, SCET = GRT(STS) + (TIM * DTIM) - propogation delay (8:00.1 sec). where SCET = Spacecraft Event Time, GRT = Ground Reception Time. The table below lists important GRT for the Encounter (Mar 13-14). GRT TIM Remarks 19:23:46.81 switch-on 19:23:47.97 00000 calculated GRT for TIM=0 (reset for TIM) 19:23:49.15 34797 start of transmission (events 1-11 are old) 19:23:49.75 00015 first event after switch-on 12039 last event before STS 19:47:34.81 STS 00006 first event after STS 48959 last event before next STS 21:24:17.51 STS 00021 first event after STS 48960 last event before next STS 23:01:00.20 STS 00005 first event after STS 35388 event before TIM-reset 00000 add 35388 to TIM 00007 event before TIM-reset 00000 add 35396 to TIM 00004 event before TIM-reset 00:11:01 closest approach 00035 add 35566 to TIM 13394 last event before next STS 00:37:42.90 STS 00004 first event after STS 48956 last event before next STS 02:14:25.81 STS 00000 first event after STS 48144 last event before switch-off 03:49:42 PIA OFF The data for these files were received as a series of F...
Instrument PIA
Temporal Coverage 1986-03-13T19:15:48Z/1986-03-14T03:41:00Z
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 ...
Creator Contact INTERNATIONAL HALLEY WATCH
Date Published 2004-03-26
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, 2004-03-26, GIO-C-PIA-3-RDR-HALLEY, V1.0. https://doi.org/10.5270/esa-dgsk768