NSSDC continues to maintain a 7-track magnetic tape capability to enable it to read the remaining 7-track tapes in its archive (mainly holding Earth science data) and also to enable it to support the rescue of older but still important data held on such tapes by groups in the distributed NASA research community. Functioning 7-track tape drives are a rarity in this community.
As one example of community support, NSSDC was sent a set of 14 7-track Univac tapes by Dr. Wendell Mendell of NASA's Johnson Space Center (JSC). These tapes contained data from the Apollo 17 Infrared Scanning Radiometer Experiment. The data, which give the surface temperature of the Moon, were acquired in 1972. They remain important today because they are still the only high resolution measurements of lunar surface thermal emission and are used to determine physical properties of the surface material, such as thermal conductivity, bulk density, and specific heat. NSSDC was able to migrate the data from the 7-track tapes to staging disk from which they were downloaded to JSC. Dr. Mendell's team is currently reprocessing and recalibrating the data and will provide a user-friendly lunar surface temperature data base back to NSSDC for community access and use.
Another example is NSSDC's reading of the first of several 7-track tapes containing Low Energy Electron (20-5000 MeV) data from a series of University of Chicago balloon flights of the 1960s and 1970s. The historic flights link electron observations made with the Orbiting Geophysical Observatory (OGO) 5 spacecraft to observations made with the International Sun-Earth Explorer (ISEE) 3/International Cometary Explorer (ICE). Current flights of the same balloon payload are providing support for Ulysses and the Solar and Heliospheric Observatory (SOHO). Because of the importance of this data set in providing continuity in the study of the long-term temporal variability of electrons, it is necessary that all phases of the analysis be directly traceable to raw data. Dr. Paul Evenson, formerly at the University of Chicago and now at the Bartol Research Foundation, has "reverse engineered" the data and documentation files recovered from the NSSDC-read tape to develop an understanding of its content. He is now setting up the flow of the remaining Chicago-held tapes to NSSDC so that the unique data can be recovered and eventually become publicly accessible.
Such efforts are welcomed by NSSDC, especially for small numbers of old tapes, when such involvement promises to yield a broadly desirable and publicly available and usable data set.
Author:Miranda Beall (firstname.lastname@example.org)