NSSDC has produced two sets of CD-ROMs containing 0.5-sec resolution electric and magnetic field data from NASA's Dynamics Explorer-2 spacecraft. This spacecraft was in a low altitude (300-600 km), near polar (89.9 deg) orbit. Data cover the period August 15, 1981, to February 16, 1983.
The data are found on a set of two IBM/PC-binary CD-ROMs, and also on a set of four ASCII CD-ROMs. MS-DOS data-retrieve-and-display software is available for the binary version. The ASCII version was created for users without MS-DOS availability.
The DE-2 data consist of various location parameters and electric field and magnetic field data in spacecraft coordinates (almost, but not quite, northward, eastward, and vertical) at 0.5-sec intervals. Three components of the magnetic field vector are given, but only two components of the electric field are given. The near-east-west component of the electric field could not be measured owing to an antenna deployment failure. (An initial version of this announcement incorrectly referred to the near-vertical component being unmeasured.)
The 0.5-sec field data are averages computed from full resolution (16 vectors/sec) data by the DE magnetometer team at Goddard. NSSDC also holds these full resolution data on 8-mm tapes.
Each set of disks also contains, in ASCII files, lower resolution values of IMP-8 and ISEE-1, -2, and -3 solar wind and magnetosphere data as well as Auroral Electrojet indices, for the DE-2 period.
In order to accommodate users needing magnetic field vectors in a true north-east-vertical coordinate system, a set of one-day ASCII files containing 5-second resolution matrices for transforming the magnetic field vectors from spacecraft coordinates to a true north-east- vertical system are included on the fourth ASCII disk. This disk, then, has 0.5-sec electric and magnetic field data in ASCII for November 1, 1982 to February 16, 1983, IMP, ISEE, and AE data in ASCII for the same period, and also has the 5-sec transformation matrices for August 15, 1981 to February 16, 1983.
Owing to differing anticipated demand levels, NSSDC has had the two binary disks, and the fourth ASCII disk with the transformation matrices, mass replicated, but will respond to requests for the ASCII version by creating CD-Recordable disks at NSSDC. Note that most CD-ROM players will read both mass replicated and CD-Recordable disks equally well. NSSDC is able to charge less for the binary version due to the mass replication.
The MS-DOS software for use with the binary disks provides a menu- based interface which enables a user to create, for a user-specified time period, an ASCII file of time and location information plus his/her choice of the following parameters: electric field data, magnetic field data, model magnetic field values, difference between the data and the model, location and difference information in Corrected Geomagnetic (CGM) coordinates, the Earth-surface footprint of the DE-2 magnetic field line, and selected other parameters. The software supports the display of plots of user-selected parameters vs. time in addition to the creation of the subsetted ASCII files for further analysis.
The MS-DOS software is available from NSSDC on a floppy disk, or it may be electronically downloaded via FTP from node NSSDCA.GSFC.NASA.GOV in the ANONYMOUS subdirectory CDROM/SOFTWARE/DOS. Its file name there is DE2_Z.EXE.
NSSDC refers to the following data sets:
Magnetic field data on the binary CD-ROMs: 81-070B-01E
Magnetic field data on the ASCII CD-ROMs: 81-070B-01F
Electric field data on the binary CD-ROMs: 81-070B-02H
Electric field data on the ASCII CD-ROMs: 81-070B-02I
Coordinate transformation matrices: 81-070B-00H
To order any combination of the disks, please contact the Request
Coordination office at NSSDC:
REQUEST@NSSDCA.GSFC.NASA.GOV
(301)-286-6695 (voice)
(301)-286-1771 (FAX)