Access to nearly every service formerly available only by logging into NSSDC's NODIS account are now also available either directly through a WWW interface or via a telnet session from NSSDC's WWW pages. Notable exceptions to this at this time are the NSSDC Master Catalog query interface and the ability to run space physics models.
The NASA Master Directory (NMD) is now available on the WWW. As discussed elsewhere in this and previous newsletters, the NMD contains information about space science data that are accessible to the science community. The WWW interface allows users to query for supplemental information (data centers, sources, sensors, and campaigns/projects) as well.
The NSSDC Master Catalog (NMC), which contains more detailed information about NSSDC's data holdings than the NMD, does not yet have (as noted above) a general query interface available via the WWW. However, limited access has been provided from a number of pages (notably the planetary science and space physics discipline pages) to the information in the NMC. On NSSDC's discipline pages project, experiment, and data set information available in this manner usually appear with black bullets.
The first of such WWW-based data systems was the OMNIWeb system that provides access to the NSSDC's ONMI data. OMNI data consist of 1-hour-resolution "near-Earth" solar wind magnetic field and plasma data, energetic proton fluxes (1-60 MeV), and geomagnetic and solar activity indices. OMNIWeb came on line at the end of November 1994, and since that time close to 2,000 plots have been created with the systems. The user community has responded enthusiastically to the OMNIWeb system.
The COHOWeb system was built immediately after the OMNIWeb system and provides similar access to Coordinated Heliospheric Observations (COHO) data. COHO data consist of multi-spacecraft magnetic field, plasma, and ephemeris data. However, COHOWeb is a more powerful implementation since the interface is built dynamically from the descriptions contained in the data. Therefore, COHOWeb is easily expandable to other time-ordered data since the data can simply be "plugged" into the existing framework with little re-engineering.
OMNIWeb and COHOWeb represent a real world framework with which to model data systems providing interactive access via the WWW. The WWW, which was originally conceived for document delivery, has now evolved into a network-based data retrieval and analysis medium.
NSSDC's support for the various disciplines continues as it highlights three new disciplines since the last newsletter article: astronomy/astrophysics, Earth science, and life science.
The Astronomy and Astrophysics Home Page has been a joint venture between the NSSDC and its sibling organization, the Astrophysics Data Facility (ADF). This page provides access to many services from both NSSDC and ADF in a manner consistent with NSSDC's other discipline home pages (planetary, space physics, solar).
As many people are aware, Earth science data continues to be transitioned out of NSSDC and turned over to the Earth Observing System (EOS) Distributed Active Archive Centers (DAACs). As a result NSSDC's new Earth Science Home Page has a different emphasis than the center's other discipline pages.
The Earth science page is intended to fulfill two different purposes. Because NSSDC has been the traditional archive for much Earth science data and is often the first place people look, the page serves as a pointer to where users should now look for the information and data they seek. In addition, because NSSDC still has not yet transitioned all Earth science data from its archives, it provides information about those data and services still available from NSSDC and expected times for transition to the DAACs.
NSSDC has been continuing to work with representatives of the Life Science Data Archive (LSDA) at Johnson Space Center and Ames Research Center to bring NASA's life science data and information on line. The first part of this information to be released on the WWW will be available in late May 1995. The first information to be released will be primarily about the SLS 1 mission with other life science missions (SL-J, SLS 2, IML) to be released as quickly as possible. The remainder of the LSDA system (e.g., the Life Science Master Catalog) is expected to be released for community access in late 1995.
The NSSDC, as part of NASA's education initiatives, supports development of the Space Science Education Home Page. The purpose of this page is to point educators and students to those resources within the Space Science Data Operations Office (NSSDC's parent organization) that can be used for education. In addition, the page provides other pages especially intended for education purposes, like the Interactive NASA Space Physics Ionospheric Research Experiment (INSPIRE). INSPIRE is a non-profit scientific, educational corporation whose objective is to bring to high school students the excitement of observing natural and man-made radio waves in the audio region.
As part of NSSDC's normal support activities for past, current, and future NASA missions, several new project pages have been added to the existing space physics and planetary discipline pages. Notable ones include the Interplanetary Monitoring Platform (IMP) 8, the International Sun-Earth Explorer (ISEE), Voyager, Pioneer Venus, Mariner 10, Lunar Prospector, and Mars Global Surveyor. The IMP 8 and ISEE pages provide access to NSSDC Master Catalog information about the missions, their experiments, and the data available from NSSDC. In addition, they both provide access to request those data available from NSSDC's Data Archive and Distribution System (NDADS).
Although not strictly speaking a new page, the CDF Home Page has been only minimally advertised to this point. The Common Data Format (CDF) is a self-describing data abstraction for the storage and manipulation of multidimensional data in a discipline-independent fashion. The CDF Home Page provides access to detailed information about the Common Data Format, retrieval of the latest version of the software, and questions of and feedback to the developers.
An entirely new addition to the extensive collection of planetary information NSSDC provides on the WWW is the planetary fact sheets. These pages provide the best estimates from the literature for various physical parameters of the planets (including the Earth and the Moon) in a uniform format.
The NSSDC has played a leading role in applying World Wide Web technology to its mission. In the process it has created or discovered WWW development tools, studied development processes, analyzed Web system usage, participated at WWW conferences, published papers as well as created many WWW systems. The NSSDC WebWorks is a "virtual" library where the center deposits its know-how, tools, publications, usage statistics, policies and guidelines, and other miscellaneous odds and ends so that it can share them with a broader audience.
A number of pages have been updated or redesigned in the last several months. The most notable of these has been NSSDC's lunar pages and the NSSDC Photo Gallery.
The lunar pages, which began as an effort to celebrate the twenty-fifth anniversary of Apollo 11's landing on the Moon, now provide access to information in NSSDC's Master Catalog on all lunar missions (U.S. and otherwise) and the data NSSDC holds from those missions. Considerable restructuring of the pages has taken place from the initial version.
Since its inception last July 1995 the NSSDC Photo Gallery has undergone a number of changes, driven by an ever increasing number of images and accesses. Still more are planned because of the limited network bandwidth to which some users are subject, the net result of which is to slow the loading of some of the larger pages. The explosive growth the NSSDC Photo Gallery has experienced (a factor of ten from September 1994 to April 1995) has made this an extremely popular visiting spot. The number of images has grown by nearly 50% since September and now includes some astronomical images. NSSDC hopes to be adding even more images, so keep watching.
NSSDC provides "What's New" pages from the NSSDC and discipline home pages as well as many other pages to help keep users informed as to what has been recently changed or added. As usual, contact information is provided at the bottom of nearly every page, but mechanisms have now been provided for feedback directly to the page developers in many cases. Please let center staff know where the NSSDC is serving your needs and where things are needed or need improving.