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Warren, W. H., Jr.

Publications and source records attributed to Warren, W. H., Jr..

At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

Documentation for the machine-readable AGK3-BD and BD-AGK3 cross-index catalogues

The machine-readable cross identification catalogs were prepared by extracting AGK3 and BD numbers from the magnetic tape version of the AGK3 Catalog. After preparation of the AGK3-BD file, which contains all stars in the AGK3 catalog, the file was sorted according to BD number and rearranged so that the BD number occurs at the beginning of each record. During the sorting operation, all AGK3 stars having no BD numbers were omitted. The BD-AGK3 file is especially useful for finding BD stars in the AGK3 catalog, since precession has moved stars across declination boundaries and it often was necessary to examine more than one AGK3 zone to locate a BD star in the catalog. The contents of the cross index files is described so that users can read and process the tape without problems, guesswork, or consulting the parent catalog.

Warren, W. H., Jr.↗
NASA NTRS1982

The astronomical data base and retrieval system at NASA

More than 250 machine-readable catalogs of stars and extended celestial objects are now available at the NASA/Goddard Space Flight Center (GSFC) as the result of over a decade of catalog acquisition, verification and documentation. Retrieval programs are described which permit the user to obtain from a remote terminal bibliographical listings for stars; to find all celestial objects from a given list that are within a defined angular separation from each object in another list; to plot celestial objects on overlays for sky survey plate areas; and to search selected catalogs for objects by criteria of position, identification number, magnitude or spectral type.

Mead, J. M.↗
NASA NTRS1982

Archiving and retrieval of data from the International Ultraviolet Explorer /IUE/ mission

The data base of IUE spectra available for dissemination to the scientific community presently contains approximately 22,000 separate images. Due to storage space and computer processing time limitations, it was decided to store the data on high density (6250 bpi) specially formatted tapes and to retrieve and reconvert them to the originally supplied format upon request. The archival/retrieval system for the data and an automatic data entry system for creation and maintenance of an indexing data base are described. Suggestion are made for the use of standard formats for future image data storage, retrieval and dissemination.

Warren, W. H., Jr.↗
NASA NTRS1982

Responsibilities and practical limitations in the operation of an astronomical data center

The operation of an astronomical data center requires that many decisions be made concerning the handling of the astronomical catalogs and data distributed. Should a data center be, as Wilkins (1977) described it, passive, in that catalogs and data are collected and distributed blackbox-wise upon request, or should a data center be active and have experts in various fields to scrutinize, correct, reformat, and document data where necessary. These questions will be addressed and illustrated by describing the current operations and future goals of the Astronomical Data Center at NASA/GSFC.

Warren, W. H., Jr.↗
NASA NTRS1981

Astronomical data bases and retrieval systems

The status of the development of machine-readable stellar and extragalactic data bases is summarized, including several examples of astronomical applications using these data sets. The creation of a computerized bibliographical data base for cometary research is described.

Mead, J. M.↗
NASA NTRS1981

Documentation for the machine-readable character coded version of the SKYMAP catalogue

The SKYMAP catalogue is a compilation of astronomical data prepared primarily for purposes of attitude guidance for satellites. In addition to the SKYMAP Master Catalogue data base, a software package of data base management and utility programs is available. The tape version of the SKYMAP Catalogue, as received by the Astronomical Data Center (ADC), contains logical records consisting of a combination of binary and EBCDIC data. Certain character coded data in each record are redundant in that the same data are present in binary form. In order to facilitate wider use of all SKYMAP data by the astronomical community, a formatted (character) version was prepared by eliminating all redundant character data and converting all binary data to character form. The character version of the catalogue is described. The document is intended to fully describe the formatted tape so that users can process the data problems and guess work; it should be distributed with any character version of the catalogue.

Warren, W. H., Jr.↗
NASA NTRS1981

Documentation for the machine-readable version of the catalog of 5,268 standard stars, 1950.0 based on the normal system N30

The machine-readable version of the N30 catalog available on magnetic tape from the Astronomical Data Center is described. Numerical representations of some data fields on the original catalog were changed to conform more closely to formats being used for star-catalog data, plus all records having asterisks indicating footnotes in the published catalog now have corresponding remarks entries in a second tape file; i.e. the footnotes in the published catalog were computerized and are contained in a second file of the tape.

Warren, W. H., Jr.↗
NASA NTRS1981

Astronomical Data Center Bulletin, volume 1, number 2

Work in progress on astronomical catalogs is presented in 16 papers. Topics cover astronomical data center operations; automatic astronomical data retrieval at GSFC; interactive computer reference search of astronomical literature 1950-1976; formatting, checking, and documenting machine-readable catalogs; interactive catalog of UV, optical, and HI data for 201 Virgo cluster galaxies; machine-readable version of the general catalog of variable stars, third edition; galactic latitude and magnitude distribution of two astronomical catalogs; the catalog of open star clusters; infrared astronomical data base and catalog of infrared observations; the Air Force geophysics laboratory; revised magnetic tape of the N30 catalog of 5,268 standard stars; positional correlation of the two-micron sky survey and Smithsonian Astrophysical Observatory catalog sources; search capabilities for the catalog of stellar identifications (CSI) 1979 version; CSI statistics: blue magnitude versus spectral type; catalogs available from the Astronomical Data Center; and status report on machine-readable astronomical catalogs.

Nagy, T. A.↗
NASA NTRS1981

Documentation for the machine-readable version of the thirteen color photometry of 1380 bright stars

The magnetic tape version of the catalogue of thirteen-color photometry of 1380 bright stars, containing data on the 13 color medium narrow band photometric system is described. Observations of essentially all stars brighter than fifth visual magnitude north of delta = -20 deg and brighter than fourth visual magnitude south of delta = -20 deg are included. It is intended to enable users to read and process the tape without the common difficulties and uncertainties.

Warren, W. H., Jr.↗
NASA NTRS1980

Documentation for the machine-readable version of an atlas of ultraviolet stellar spectra and a second atlas of ultraviolet stellar spectra from OAO 2 observations

The magnetic tape version of the Orbiting Astronomical Observatory 2 atlases of ultraviolet stellar spectra is described. The first file of the tape contains ultraviolet stellar fluxes for 164 bright stars in lambda the spectral region 1200 to 1300 A with resolutions of 22 A in the region from 3600 to 1850 A and 12 A in the region from 1850 to 1160 A. Files two and three contain spectra for 132 stars in the region lamba 1200 to 1850 A and 34 stars in the lambda region 1800 to 3600 A, respectively, with resolutions as stated above. The monochromatic flux is given in units of ergs cm(-2)s(-1) (-1) for all data.

Warren, W. H., Jr.↗
NASA NTRS1980

Documentation for the machine-readable version of the Perth 70: A catalogue of positions of 24900 stars tape B, mean values of the observation

The Perth 70 catalog contains accurate positions of 24978 stars, plus other useful data such as approximate proper motions, radial velocities, and parallaxes. The Perth 70 is a result of meridian circle observations made by the Hamburg observatory expedition to Perth as part of the international effort of Southern References Stars (SRS). Tape B, which contains mean values of the observations and corresponds to the printed catalog is described.

Warren, W. H., Jr.↗
NASA NTRS1980

Astronomical Data Center Bulletin, volume 1, no. 1

Information about work in progress on astronomical catalogs is presented. In addition to progress reports, an upadated status list for astronomical catalogs available at the Astronomical Data Center is included. Papers from observatories and individuals involved with astronomical data are also presented.

Warren, W. H., Jr.↗
NASA NTRS1977

A photometric study of the Orion OB 1 association. 3: Subgroup analyses

The four principal subgroups of the association were examined in detail using individual distances and reddening values determined for their B type members. Subgroup 1a appeared not to show a spread in age nor did it show a systematic distance increase with right ascension when fainter members were considered. An eastwardly increase in distance was found for subgroup 1b but the reddening law for the east Belt appeared normal. Small subclusterings in the vicinity of the Orion Nebula appeared not to differ in the evolutionary state but their ages were considerably greater than those of stars in the nebulae and its associated cluster.

Warren, W. H., Jr.↗
NASA NTRS1977

A photometric study of the Orion OB 1 association. I - Observational data. II - Photometric analysis

A catalog of observational data is presented for stars in the region of the young stellar association Orion OB 1. Photoelectric observations obtained in the uvby-beta and UBV systems are compiled along with previous photoelectric and spectroscopic data for all these stars as well as for several bright members of the association with available photometric indices. Mean weighted values are computed for the photometric data and summarized in tables expected to be reasonably complete for association members earlier than spectral type A0. Membership criteria are derived, and qualitative membership probabilities summarized, for the 526 stars in the final program. The analytical procedures are discussed for association stars of B, intermediate, and AF types. Effects of the nebular environment and various calibrations of Balmer-line and four-color indices are considered for the determination of absolute magnitudes for the B-type stars.

Warren, W. H., Jr.↗
NASA NTRS1976

A photometric study of the Orion OB 1 association. 2: Photometric analysis

The procedures adopted for analysis of photometric data in terms of color excesses, intrinsic color indexes, absolute visual magnitudes, and rotational-velocity effects are discussed in detail for Orion association B-, intermediate (I)-, and AF-type stars. The effects of the nebular environment and a comparison of various calibrations of Balmer-line and four-color indexes are considered for the determination of individual absolute magnitudes for B-type stars. When absolute magnitudes of stars in the region of the Orion Nebula are determined from the beta index, emission mechanisms appear to spuriously brighten them. A detailed comparison of absolute magnitudes derived from Balmer-line indexes and MK spectral-type calibrations is presented. The data are also examined with regard to the effects of polarization and infrared excesses. The results suggest a complex combination of intracluster and circumstellar origins for these processes.

Warren, W. H., Jr.↗