The HEASARC Online Service
The HEASARC currently has over 140 databases available for browsing within the Online Service. The following is the listing of SYSTEM databases:
Name Description ObservatoryRecent additions to the HEASARC Online Service
ASCALOG - ASCA Observations Log
The ASCALOG database contains the ASCA observations log for phases IT (instrument turn-on), PV (performance verification), and AO1.
ASCAPUBLIC - ASCA Archive Public
This table contains a record of data from the ASCA mission that is available from the HEASARC archive. The listing includes future data which may not yet be in the public domain. The data will initially be released in one-month batches, around the 15th of each month, with the first batch released on November 15, 1994. As the archive population becomes routine, the releases will be made more often, on a weekly basis.
BD - Bonner Durchmusterung
The BD database contains the Bonner Durchmusterung visual survey of stars in the declination zones +89 to -01 degrees. The survey, completed by Argelander and his assistants in the years 1852-1861, was performed and the stars cataloged by allowing the telescope to drift along the mean declination of each zone and recording the positions and magnitudes of stars crosssing the transit line of each field. The goal of the survey was to obtain a position and estimated visual magnitude for every star visible with the 78-mm Bonn telescope. Actual magnitude estimates were made and reported to 0.1 mag for all stars down to 9.5 mag, with fainter stars being assigned to 9.5. Thus, the BD actually contains a rather large number of stars fainter than 10.0 mag. Positions are given to the nearest 0.1 sec in right ascension and 0.1 arcmin in declination.
BESTARS - Catalogue of Be Stars
The BESTARS database contains the Catalogue of Be Stars, a compilation of data concerning stars of type Be. For the purposes of this compilation, a Be star is defined as a non-supergiant B star which showed emission in one Balmer line at least once. Stars without published MK spectral types have been excluded except for 132 stars from Bidelman and MacConnell (1973), who used the above definition but included no spectral types. There are 1159 stars included in this list.
BSC5P - Bright Star Catalog
The BSC5P database contains data derived from the Bright Star Catalog, 5th Edition, preliminary, which is widely used as a source of basic astronomical and astrophysical data for stars brighter than magnitude 6.5. The database contains the identifications of included stars in several other widely-used catalogs; double- and multiple-star identifications; indication of variability and variable-star identifiers; equatorial positions for B1900.0 and J2000.0; galactic coordinates; UBVRI photoelectric photometric data, when they exist; spectral types on the Morgan-Keenan (MK) classification system; proper motions (J2000.0); parallax; radial- and rotational-velocity data; and multiple-star information (number of components, separation, and magnitude differences) for known nonsingle stars.
CPSTARS - General Catalog of Ap and Am
CPSTARS is derived from data contained in the General Catalogue of Ap and Am Stars by Renson, Gerbaldi, and Catalano. The catalog contains 6684 objects which represents a collection of all Ap and Am stars discovered to date (1991).
EUVEBSL - First EUVE Bright Source List
This catalog contains a detailed list of verified bright EUVE sources detected during the survey phase of the EUVE mission (calibration targets are also included). Two distinct surveys, the all-sky and deep surveys, were conducted by the four EUVE telescopes during the first six months of the mission.
EUVECAT1 - The First EUVE Source Catalog
The EUVECAT1 database contains a detailed list of verified bright sources detected during the survey phase of the Extreme Ultraviolet Explorer (EUVE) mission (calibration targets are also included). Additionally, this database includes the sources derived from the First EUVE Source Catalog Supplementary list, which were a part of the Bright Source List (BSL) but not formally included in the First EUVE Source Catalog (FESC) because they did not meet the criteria for inclusion.
EXOFOT - EXOSAT Final Observation Tape
The EXOFOT database contains the log of the EXOSAT final observation tapes (FOTs). This database helps to locate the desired EXOSAT data file within the HEASARC anonymous FTP account. The database itself contains a minimum number of parameters regarding the observation which correspond to the first 255 bytes which label the FOT. Those parameters are target name, experiment, and start and stop time. Other parameters in the database are more related to the organization of the archive.
The European X-ray Observatory Satellite (EXOSAT) was operational from May 1983 to April 1986 and in that time made 1780 detailed observations of a wide variety of astronomical objects. The scientific payload consists of two energy telescopes (LEIT), a medium energy proportional counter (ME), and a gas scintillator proportional counter (GSPC).
The data acquired for the four instruments were distributed to observers as FOT (Final Observation Tape) in a form of 1600 BPI tape. A single FOT contains data for only one instrument, and a FOT (observation) could consist of more than one 1600 BPI tape, which generally contained data from the pointed observation plus part of the in-going and out-going slews (only for the GSPC and ME instruments).
Since 1992, the total amount of ~8643 tapes (1600 BPI), for a volume of 150 Gbytes of data, has been archived at ESRIN/ESA, on an optical disk, by the ESIS project. An exact copy has been given to HEASARC/GSFC (Greenbelt, MD, USA). From ESRIN the data arrived at HEASARC on magnetic media, each containing a number of FOTs. At HEASARC the magnetic tapes were read into a jukebox organized into directories named from the magnetic tape number delivered from ESRIN.
ESIS could not recover and archive the complete mission because some of the earliest 1600 BPI tapes (now over ten years old) were badly damaged. Currently there are about 50 observations for which data recovery was not possible. Letters have been sent to the original PIs of those observation in the hope that their copies of the data were better maintained. For a number of observations (in particular for the early ones), more than one FOT is available. This is because the FOT was regenerated for various reasons. The record seems to be missing as to which is the correct FOT.
EXOGPS - EXOGPS Source Catalog
This catalog is based on information contained in Warwick et al (1988), MNRAS, 232, 551.
The distribution of 2-6 keV x-ray emission in the galactic plane in the first and fourth galactic quadrants has been measured in a series of scanning observations with the medium-energy progportional counters on EXOSAT. The results are presented as contour maps and in the form of a catalogue of 70 discrete sources.
HRIDEEP - HRI Deep Survey Source
This database contains primary HRI source parameters for the 202 HRI sources found in the Einstein Deep Survey. The Einstein Deep Survey program (EDS) consists of very deep X-ray exposures in selected regions of the sky at high galactic latitude. The main purposes of the survey are to investigate the nature of the extragalactic X-ray background through direct source counts at very low flux levels and to study the nature of the very faint X-ray sources which comprise a significant fraction, if not all, of the soft X-ray background.
HIIREGION - Sharpless H II Region Catalog
The HIIREGION database is derived from data contained in the Sharpless Catalogue of H II regions. The original catalogue was published in 1959 in the Astrophysical Journal Supplement Series (number 41, pages 257-280). The original card deck was in the 026 punch and this was converted to a 029 deck. Many of the quantities in this version of the catalogue were not in the published catalogue. The epochs of the precessed equatorial coordinates were determined empirically from the data as given on the computer cards.
HSTOBS - HST Observation Catalog
The HSTOBS database is created from an ASCII listing compiled from the Hubble Space Telescope Data Archive and Proposal databases. It provides a summary of all approved HST observations, including already completed observations and those which are planned to be executed as part of Cycle 4 or which are reserved for execution in Cycle 5 Guaranteed Time Observer (GTO) programs.
HSTEXP - HST Exposure Catalog
The HSTEXP database is created from an ASCII listing compiled from the Hubble Space Telescope Data Archive database. It provides a summary of completed HST science observations.
IPCDEEP - IPC Deep Survey Source
IPCDEEP is created from a table containing basic source parameters for each of the 178 IPC sources detected by the Einstein Deep Survey. The Einstein Deep Survey program (EDS) consists of very deep X-ray exposures in selected regions of the sky at high galactic latitude. The main purposes of the survey are to investigate the nature of the extragalactic X-ray background through direct source counts at very low flux levels and to study the nature of the very faint X-ray sources which comprise a significant fraction, if not all, of the soft X-ray background.
MCG - Morphological Catalogue of Galaxies
The MCG database contains the Morphological Catalogue of Galaxies, a compilation of information for approximately 34,000 galaxies found and examined on the Palomar Observatory Sky Survey (POSS). Individual identifiers are assigned for about 29,000 galaxies and information on the remaining 5000 is present in the extensive notes of the published catalogs (Vorontsov-Velyaminov et al. 1962-1968). The catalog is structured according to the POSS zones and is numbered from +15 (corresponding to +90 deg) to +01 (+06 deg zone) and +00 (equatorial zone) to -05 (-30 deg zone); the fields are numbered with increasing right ascension. The original goal of the compilation was to be complete for galaxies brighter than magnitude 15.1, but the final catalog lists many objects considerably fainter.
NGC2000 - NGC 2000.0 Catalogue
NGC 2000.0 is a modern compilation of the New General Catalogue of Nebulae and Clusters of Stars (NGC), the Index Catalogue (IC), and the Second Index Catalogue compiled by J. L. E. Dreyer (1888, 1895, 1908). The new compilation of these classical catalogs is intended to meet the needs of present-day observers by reporting positions at equinox 2000.0 and by incorporating the corrections reported by Dreyer himself and by a host of other astronomers who have worked with the data and compiled lists of errata. The object types given are those known to modern astronomy.
OSTARS - Galactic O-Type Stars Catalog
OSTARS database is based on the information contained in the Catalog of Galactic O-Type Stars (Garmany, Conti, and Chiosi 1982), a compilation from the literature of all O-type stars for which spectral types, luminosity classes, and UBV photometry exist. Most of the entries come from Cruz-Gonzalez, et al. (1974) and Humphreys (1978), with additional stars from Garrison and Kormendy (1976); Garrison, Hiltner, and Schild (1977); Garrison and Schild (1979); Feinstein, Marraco, and Muzzio (1973); Feinstein, Marraco, and Forte (1976); and Moffat, FitzGerald, and Jackson (1979). The catalog contains 765 stars, for each of which designation (HD, DM, etc.), spectral type, V, B-V, cluster membership, Galactic coordinates, and source references are given. In addition, the authors have included derived values of absolute visual and bolometric magnitudes and distances.
PLNEBULAE - Strasbourg Galactic Planetary
The PLNEBULAE database is designed to provide a list of data concerning all known planetary nebulae (PN). The total number is 1455 including 1036 listed in the Perek and Kohoutek (PK) catalogue (1967), and including doubtful cases. The additions come from Sanduleak (1975, 1976); Acker and Marcout (1977); Weinberger (1977); Peterson (1977); Kohoutek (1978); Stephenson (1978); Allen (1979); Murdin et al. (1979); Van den Bergh (1979); and Purgathofer and Weinberger (1980).
PMN - PMN Southern & Tropical Surveys
The PMN database contains data from the PMN Southern and Tropical surveys. The data is measured at a frequency of 4850 Hz, using the Parkes 64 m radio telescope with the NRAO multibeam receiver. These surveys cover 4.51 sr and contain 36,640 sources to a flux limit that is typically about 35 mJy but varies as a function of declination. They increse the number of known sources in the regions surveyed by approximately a factor of 5.
PPM - Positions and Proper Motions
The PPM database is the Catalog of Positions and Proper Motions. It combines the two catalogs for PPM North and PPM South and the Bright Stars Supplement to PPM. PPM North gives positions and proper motions of 181,731 stars north of -2.5 degrees declination. PPM South gives positions and proper motions of 197179 stars south of about -2.5 degrees declination. The star density of PPM South is slightly higher than that of its northern counterpart and the accuracy of the present-epoch positions is roughly twice that in the north.
The Bright Stars Supplement makes the PPM catalogues complete down to V=7.5 mag. For this purpose it lists all missing stars brighter than V=7.6 mag that could be found in published star lists. Their total number is 321. Only 5 of them are brighter than V=3.5.
ROSATSRC - ROSAT PSPC Sources from
REV0/1 Public Pointings
This catalog contains ROSAT point sources detected by the standard analysis system SASS. The catalog is based on the public PSPC observations.
During the ROSAT workshop at MPE on October 26, 1994, Wolfgang Voges announced on behalf of the ROSAT Consortium (MPE-Garching, GSFC/SAO-US, and WFC-Consortium-UK) the public release of "THE FIRST ROSAT SOURCE CATALOGUE OF POINTED OBSERVATIONS WITH THE PSPC." This catalogue contains 50,408 sources from 2876 pointed observations. For each source the following properties are provided: the observation number, the ROSAT name, the position in equatorial and in galactic co-ordinates, four positional errors (intrinsic, systematic, boresight, and total), the source count-rate and its error, the background countrate, exposure time, hardness-ratios HR1 and HR2 and their errors, extent and likelihood of extent, likelihoods of the map-detect algorithm and of the maximum-likelihood detection algorithm, flags to indicate in which energy band and by what algorithm the source was detected, the detection cell size, the off-axis radius, the distances to the nearest rib and source (before and after removal of ambiguous sources), and a source confusion flag (set if another source is within 2.1*FWHM of the point-spread function).
This catalogue contains observations which have been performed until the end of May 1993 and which are in the public archive. A visual inspection of all soft and hard images, and an automated screening process on the original so called master source lists (MASOL), have been used to remove confused sources and 124 observations with too crowded regions and regions of high surface brightness diffuse emission. The resulting 50,408 sources have a likelihood of at least 10, corresponding to a rate of accidental detections of about 1 percent. This data base contains 80% of all PSPC observations. Since the acceptance criteria were rather conservative a total number of about 70,000 X-ray sources detected during the pointed PSPC observation phase can be expected.
ROSDISTRIB - ROSAT Distributed Data
The ROSDISTRIB database contains the list of US and German ROSAT observations for which data have been distributed to the PI, including those data sets which have become available to the public. ROSDISTRIB is updated weekly, or as new data sets are distributed to PI's.
ROSPUBLIC - ROSAT Public Archive List
The ROSPUBLIC database contains the list of public US and European ROSAT observations which have been released to the US archive. ROSPUBLIC is updated as new data sets are released for public use. ROSPUBLIC currently contains all data released to the US archive through 12 Oct 1994. This includes the following:
US data public through Sep 1994
German/UK data public through May 1994
VERON91 - Quasars and AGN
The VERON91 database is the 5th edition of Veron-Cetty & Veron "A Catalogue of Quasars and Active Galactic Nuclei (1991)." It contains data for quasars, active galaxies, and BL Lac objects.
VLANEP - VLA North Ecliptic Pole Survey
The VLANEP database contains the VLA-NEP survey of 29.3 square degrees around the North Ecliptic Pole mapped with the VLA at 1.5 GHz in the `C-configuration`. The database contains 2435 radio sources with flux densities ranging from 0.3 - 1000 mJy, including over 200 fainter than 1 mJy. Source positions have been corrected for instrumental effects, and most positions are accurate to less than 2 arcseconds.
WFCPOINT - ROSAT WFC Observations
The WFCPOINT database contains the current list of ROSAT-Wide Field Camera CAL, PV, and AO phase observations.
For each observation listed in WFCPOINT, the target name, celestial co-ordinates, sequence number, PI name, and proposal title are given. The date of the observation, date that the data were distributed, and the date that the data will be released to the public are also given. The public release date is nominally 1 year and 14 days after the distribution date; however, because of some processing problems with a few datasets, the actual release date will be delayed from the given date. The public flag indicates whether or not a dataset is currently available for public release.
WGACAT - ROSAT WGA Point Sources
WGACAT is a point source catalogue generated from all ROSAT PSPC pointing observations from Feb 1991 to March 1994 which were available in the public archive at HEASARC in September 1994. This catalog has been generated by N.E. White (HEASARC/GSFC), P. Giommi (ESIS/ESA), and L. Angelini (HEASARC/GSFC), and is a private research effort not related to the official catalog planned by the ROSAT project. The total number of sequences processed were 2624 and include all of the US and German/UK public archived data. As more data becomes available, the catalog will be updated. The catalog currently (Oct 30, 1994) contains in excess of 50,000 detections, with more than 45,600 individual sources.
This catalog was generated using an optimized sliding cell detect algorithm in XIMAGE (first developed for the EXOSAT project). The inner and outer parts of the images were run separately to maximize the sensitivity to source detection. This method is very sensitive to finding point sources, but can also find spurious sources where there is extended emission. We have run a quality check on the detect output and removed the obvious spurious cases, but users should carefully check the reality of each source.
Access to the HEASARC Online Service
Via the xray Account
Users can access the HEASARC Online Service by typing
From the HEASARC> prompt, the user can browse any of the (currently) 145 databases by typing browse database_name. An extensive online help is available by typing a question mark, ?, at any prompt. Information about the database that you are browsing is obtained by typing dbhelp. A Users Guide and Available Databases guide are available by e-mailing Steve Drake at firstname.lastname@example.org.
Via the ftp Account
Users can ftp to legacy.gsfc.nasa.gov to get data or documentation. To access the ftp account, simply type
and, when prompted, log on as anonymous (or ftp) with the password as your e-mail account. Anonymous ftp has no graphical capabilities, but is a quick and easy way to transfer data if you know what you're looking for. To list the contents of a directory, type ls or dir, and to change directory, type cd dir_name.
Via the WWW
The HEASARC Online Service is available via the World Wide Web (WWW). The URL for the HEASARC is
and the Browse area can be access by clicking on the Browse button at the top or bottom of the HEASARC Home Page. Searches by RA and Dec and by name are the only searches enabled on the WWW at this time. The advantage to the WWW is that the user can view the data before transferring it.
Users can connect to the HEASARC via a Gopher by typing
(or gopher heasarc.gsfc.nasa.gov).
The advantages of a gopher are that the user need not know details such as the node name or e-mail address of other internet services, the ability to immediately display files before transferring, and the ability to do searches in a directory for files with names containing a specified alphanumeric string.
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