After launch by Space Shuttle Discovery STS-41 on October 6, 1990, the Ulysses spacecraft was boosted on a path towards a flyby of Jupiter on February 8, 1992. The Jupiter encounter swung the spacecraft out of the ecliptic into a heliocentric orbit inclined about 80 degrees to the ecliptic and with a period of about six years. In June 1993, Ulysses passed beyond the maximum heliographic latitude (32 degrees south) reached by any other heliospheric spacecraft (Voyager 1), afterwards, traversing the south polar region (above 70 degrees) of the Sun from June through November 1994 and the north polar region from June through September of the next year. An approved extension of mission operations into the next solar maximum will provide further solar polar science from polar traversals from September 2000 through January 2001 (south pole) and from August through December 2001 (north pole).
The Ulysses science experiments were described in the Ulysses Instruments Special Issue of Astronomy and Astrophysics (Astron. Astrophys. Suppl. Ser., 92(2), Jan. 1992). These instruments are listed in Table 1, and their layout on the spacecraft body is shown in a Web-accessible NSSDC) has been specified in a project data management plan and agreed upon by the Ulysses Project, NASA Headquarters, and NSSDC. This plan was formally approved in November 1994 and specifies that reduced (experimenter unit) and analyzed (scientific unit) data, along with associated documentation and software, will be submitted to NSSDC within two years of original data receipt by the Ulysses experimenters. NSSDC will serve as the primary archive for interplanetary cruise data and as the deep archive for all Ulysses data. Jupiter-related data will first be submitted to the Planetary Data System (PDS) and then subsequently transferred to NSSDC after PDS processing and peer review. NSSDC will further receive and hold in proprietary status all Ulysses CD-ROM data in Experimenter Data Record (EDR) format. One exception to the proprietary status of the CD-ROM data is that NSSDC can extract Ulysses ephemeris data in the Supplementary Experiment Data Record (SEDR) format for public distribution. (Note that most PI-provided data sets will have some included ephemeris data.)
Much Ulysses data will be electronically acquired by NSSDC from ESA's Ulysses Data System (UDS), or from individual investigator sites on the Internet. UDS was originally implemented as a prototype online archive for distribution of proprietary Ulysses data among the experiment investigators and now also serves as a primary distribution point for data acquisition by the NASA archives. An average of 0.1 gigabytes per month of nonproprietary Ulysses data is presently expected to be ingested by NSSDC, usually via the Internet, and made available to users. Table 2 shows most of the data sets presently expected at NSSDC by the time of this article. Some Ulysses data sets, including solar wind plasma, magnetic field, and energetic particle data, will be staged through NSSDC's Coordinated Heliospheric Observations (COHO) data base which will provide immediate online accessibility via anonymous ftp ( access at account email@example.com, directory anon_dir:[000000.coho] ) and the World Wide Web (note that it's still partially under construction.) Eventually, all digital data sets, whether initially ingested on line or off line (e.g., on CD-ROMs or high density tapes) will be migrated to NSSDC's near-line archive environment, the NSSDC Data Archive and Distribution System NDADS. Graphical browse and display accessibilities are planned for selected Ulysses data parameters in the future through a Web-based service to be called COHOWeb, similar to NSSDC's new OMNIWeb service for near-Earth interplanetary data.
NSSDC staff will continue discussions with the Ulysses investigators on identification and acquisition of new data sets through official presentations and negotiations at periodic meetings of the Ulysses Science Working Team and through individual contacts with the investigators. These discussions have recently included an NSSDC briefing of representatives from the URAP team on new automated software for production of Standard Formatted Data Unit (SFDU) metadata in accordance with NASA's increasing emphasis on usage of evolving data standards technology. This briefing was supported by staff from the NASA/OSSA Office of Standards and Technology (NOST) in the Interoperable Systems Office at NSSDC. Space physics expertise related to Ulysses science and data is provided by acquisition scientists associated with the NASA Space Physics Data Facility (SPDF), co-located with NSSDC in the NASA Goddard's Space Sciences Directorate. Continuing technical collaboration between NSSDC/SPDF, PDS, UDS, and the investigators will ensure the expeditious and comprehensive archiving and public accessibility of Ulysses data during the prime and extended mission phases.
Questions about Ulysses data archiving and access at NSSDC should be directed by E-mail to Dr. John F. Cooper, the Ulysses Acquisition Scientist, at the Internet address: firstname.lastname@example.org.
Table 2: Ulysses Data Sets at NSSDC
Exp. PI Brief Data Set Description Start Date End Date SEDR Ulysses Project Spacecraft Ephemeris Data 1990-11-01 1991-02-28 1993-12-01 1994-11-30 GRB K. C. Hurley Integral 0.5-s Counting Rates 1990-10-29 1994-09-17 HISCALE L. J. Lanzerotti Full Resolution Particle Data 1990-11-14 1991-12-31 Hourly Average Data 1990-11-14 1991-12-31 Particle Anisotropy Plots 1990-11-15 1991-12-31 SWICS G. Gloeckler/J. Geiss 3.5-Hour Averaged Cruise Data 1990-12-07 1993-12-31 SWOOPS J. Phillips High-Resolution & 1-Hr SW Ions 1990-11-18 1993-12-31 High-Resolution SW Electrons 1990-11-18 1992-12-31 URAP R. G. Stone 3-Hour Summary Plots 1990-11-05 1994-09-26 Daily Summary Plots 1990-11-05 1994-03-31 10-Min Average/Peak Intensity 1990-11-05 1994-03-31 DUST E. Gruen Dust Particle Event Listing 1990-10-28 1992-12-29 MAG A. Balogh 1-Hour RTN Vectors & Magnitude 1990-10-25 1992-02-02URL List for document construction:
JHU/APL Ulysses Spacecraft & ESA Emblem
JPL Ulysses Mission Profile Plot
JPL Ulysses Mission Status Rep. No. 5, July 1994
STS-41 Shuttle Mission
ESA/ESTEC: Ulysses Scientific Instruments
WELCOME TO THE NSSDC!
The NSSDC Data Archive and Distribution System
COHO Home Page
PDS Home Page
PDS/PPI Home Page
NASA/Goddard Space Flight Center
NASA/GSFC Space Sciences Directorate
Space Physics Data Facility
Ulysses Project Home Page at NSSDC/SPDF