OVERVIEW OF ISTP-RELEVANT SPACECRAFT

The file below was initially prepared for inclusion in the Proceedings of the 31st COSPAR Assembly (Birmingham, 1996). It provides an overview of many spacecraft and their data relevant to the International Solar Terrestrial Physics Program. While it had been intended to keep this page current, this has not happened due to the press of other activities. Rather than taking this page offline due to its non-currency, however, we chose to keep it available as a possibly useful snapshot of the international array of ISTP-relevant spacecraft as of 1996.

An html-based index is provided below for jumping directly to spacecraft-specific parts of this paper. The reader is advised to read the introductory material on his first access to this paper.

Index of Paper

ACE             main body    appendix
AKEBONO         main body    appendix
ASTRID          main body    appendix
DMSP            main body    appendix
EQUATOR-S       main body    appendix
ETS-VI          main body    appendix
FAST                         appendix
FREJA           main body    appendix
GEOTAIL                      appendix
GMS-4           main body    appendix
GOES            main body    appendix
GOMS                         appendix
IMP-8           main body    appendix
INTERBALL-TAIL               appendix
INTERBALL-AURORA             appendix
LANL S/C        main body    appendix
MSX             main body    appendix
NOAA/TIROS      main body    appendix
OERSTED         main body    appendix
POLAR                        appendix
PRACTICE-4      main body    appendix
ROCSAT          main body    appendix
SAMPEX          main body    appendix
SOHO                         appendix
UARS            main body    appendix
WIND                         appendix

ADDITIONAL SPACECRAFT DATA SOURCES CONTRIBUTING TO THE ISTP PROGRAM

J. H. King

NASA Goddard Space Flight Center, National Space Science Data Center, Code 633, Greenbelt, Maryland 20771

ABSTRACT

Descriptions of the most salient characteristics of several spacecraft and associated data relevant to the science objectives of the International Solar Terrestrial Physics (ISTP) program are given. An appendix uniformly describes all relevant spacecraft and lists URL's when available. The body of the paper gives further descriptive material concerning the subset of these spacecraft that have not been considered as "core" ISTP spacecraft. The core spacecraft are further described in the accompanying papers in this proceedings.

INTRODUCTION

A great many spacecraft and other investigations are contributing and will contribute to the success of the International Solar Terrestrial Physics (ISTP) program. This paper is part of a series presented at the Inter-Agency Solar Terrestrial Physics (IASTP) Program Symposium of the 31st COSPAR Scientific Assembly (Birmingham, 1996) addressing those investigations and the results thereof. (ISTP and IASTP are substantively identical; we use "ISTP" herein.) This paper specifically identifies all the relevant spacecraft making in situ fields and particles measurements from 1992 onwards. These spacecraft range from those centrally involved in ISTP to those not officially part of ISTP but having potential to contribute to ISTP research objectives. The appendix lists these spacecraft and gives very limited information about each. The rest of this paper is intended to offer more detailed descriptions of the investigations on and data from those spacecraft about which spacecraft-specific papers are NOT to be part of this series of papers.

The spacecraft are grouped approximately by altitude: those mainly in the solar wind, some of which provide some magnetotail data; eccentric near-equatorial; geosynchronous; high-altitude polar; and low altitude. In each group the spacecraft are addressed in the sequence of their launch dates. Note that we have not tried to include solar remote sensing investigations.

SOLAR WIND SPACECRAFT

IMP 8

The NASA Interplanetary Monitoring Platform 8 (IMP 8) spacecraft has been acquiring magnetic field, plasma, and energetic particle data from its 35 Re, 12+ day orbit since its 1973 launch. It is in the solar wind typically 7 days of each 12+ day orbit and in the magnetosheath and magnetotail otherwise. Because of its 45 deg inclination, it has seasons of passing through the mid-tail (Y GSM, Z GSM near zero) and other seasons of passing only through the magnetotail lobes. In 1996 its mid-tail seasons are centered on December-January and June-July, and its northern tail lobe season is centered on September-October.
The IMP 8 spacecraft has no on-board data storage. It transmits data continually and depends on availability of a VHF ground station's being visible to it for telemetry capture. Over the years net IMP coverage has ranged from 90% early in the IMP 8 life to about 50% in the early 1980's, recovering to 60%-70% in the mid-1980's through mid-1990's. At present, because of the addition of a VHF antenna at McMurdo Sound, Antarctica, monthly coverage exceeds 90%. A slippage back to 70% is probable in the coming few years because of budget austerity.
Table 1 lists the IMP 8 investigations that are still being supported for data processing, analysis, and archiving.

Table 1.  Active IMP 8 Investigations

Magnetometer:           R.P. Lepping, GSFC
Solar Wind Plasma:      J.T. Gosling, LANL
                        A.J. Lazarus, MIT
Energetic Particles:    R.B. Decker/S.M. Krimigis, JHU/APL
                        F.M. Ipavich, U. Maryland
                        C. Lopate/J.A. Simpson, U. Chicago
                        R.E. McGuire, GSFC
                        D.J. Williams, JHU/APL

Data from the magnetometer (all orbital phases) and MIT plasma investigation (a split-collector Faraday Cup; solar wind phase only) are routinely flowing into the ISTP Central Data Handling Facility (CDHF) as 1-min magnetic field vectors (GSE and GSM) and plasma flow parameters (velocity vector, density, thermal speed).

More generally, data from all IMP investigations are becoming publicly available over the WWW and through more traditional pathways. Check http://nssdc.gsfc.nasa.gov/space/imp-8.html for further information.