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1. Astrographic Catalog of Reference Stars
ID:
ivo://nasa.heasarc/acrs
Title:
Astrographic Catalog of Reference Stars
Short Name:
ACRS
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
For a number of years there has been a great demand for a high-density catalog of accurate stellar positions and proper motions that maintains a consistent system of reference over the entire sky. The Smithsonian Astrophysical Observatory Star Catalog (SAO; SAO Staff 1966) has partially met those requirements, but its positions brought to current epochs now contain errors on the order of 1 second of arc, plus the proper motions in the SAO differ systematically with one another depending on their source catalogs. With the completion of the Second Cape Photographic Catalogue (CPC2; de Vegt et al. 1989), a photographic survey comparable in density to the AGK3 (Dieckvoss 1975) was finally available for the southern hemisphere. These two catalogs were used as a base and matched against the AGK2 (Schorr & Kohlschuetter 1951-58), Yale photographic zones (Yale Trans., Vols. 11-32), First Cape Photographic Catalogue (CPC1; Jackson & Stoy 1954, 55, 58; Stoy 1966), Sydney Southern Star Catalogue (King & Lomb 1983), Sydney Zone Catalogue -48 to -54 degrees (Eichhorn et al. 1983), 124 meridian circle catalogs, and catalogs of recent epochs, such as the Carlsberg Meridian Catalogue, La Palma (CAMC), USNO Zodiacal Zone Catalog (Douglass & Harrington 1990), and the Perth 83 Catalogue (Harwood [1990]) to obtain as many input positions as possible. All positions were then reduced to the system of the FK4 (Fricke & Kopff 1963) using a combination of the FK4, the FK4 Supplement as improved by H. Schwan of the Astronomisches Rechen-Institut in Heidelberg, and the International Reference Stars (IRS; Corbin 1991), then combined with the CPC2 and AGK3. The total number of input positions from which the ACRS was formed is 1,643,783. The original catalog is divided into two parts. Part 1 contains the stars having better observational histories and, therefore, more reliable positions and proper motions. This part constitutes 78 percent of the catalog; the mean errors of the proper motions are +/-0.47 arcsec per century and +/-0.46 arcsec per century in right ascension and declination, respectively. The stars in Part 2 have poor observational histories and consist mostly of objects for which only two catalog positions in one or both coordinates were available for computing the proper motions. Where accuracy is the primary consideration, only the stars in Part 1 should be used, while if the highest possible density is desired, the two parts should be combined. The ACRS was compiled at the U. S. Naval Observatory with the intention that it be used for new reductions of the Astrographic Catalogue (AC) plates. These plates are small in area (2 x 2 deg) and the IRS is not dense enough. Whereas the ACRS was compiled using the same techniques developed to produce the IRS, it became clear as the work progressed that the ACRS would have applications far beyond its original purpose. With accurate positions and proper motions rigorously reduced to both the FK4 and FK5 (Fricke et al. 1988) systems, it does more than simply replace the SAO. Rather, it provides the uniform system of reference stars that has been needed for many years by those who require densities greater than the IRS and with high accuracy over a wide range of epochs. It is intended that, as additional observations become available, stars will be migrated from Part 2 to Part 1, with the hope that eventually the ACRS will be complete in one part. Additional details concerning the compilation and properties of the ACRS can be found in Corbin & Urban (1989) except that the star counts and errors given here supersede the ones given in 1989. The HEASARC revised this database table in August, 2005, in order to add Galactic coordinates. This is a service provided by NASA HEASARC .
2. Be Stars Catalog
ID:
ivo://nasa.heasarc/bestars
Title:
Be Stars Catalog
Short Name:
Be
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The BESTARS database tables contains 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 1,159 stars included in this list. This is a service provided by NASA HEASARC .
3. Bright Star Catalog
ID:
ivo://nasa.heasarc/bsc5p
Title:
Bright Star Catalog
Short Name:
BSC
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The BSC5P database table 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 non-single stars. This table was created by the HEASARC in 1995 based upon a file obtained from either the ADC or the CDS. A number of revisions have been made by the HEASARC to this original version, e.g., celestial positions were added for the 14 non-stellar objects which have received HR numbers: HR 92, 95, 182, 1057, 1841, 2472, 2496, 3515, 3671, 6309, 6515, 7189, 7539 and 8296. In January 2014, the very incorrect position for HR 3671 = NGC 2808 was fixed (the Declination is -65 degrees not +65 degrees!), and smaller corrections were made to the positions of HR 2496, 3515 and 6515 so as to bring them in better agreement with the positions listed in SIMBAD and NED This is a service provided by NASA HEASARC .
4. Carina Nebula Chandra X-Ray Point Source Catalog
ID:
ivo://nasa.heasarc/carinacxo
Title:
Carina Nebula Chandra X-Ray Point Source Catalog
Short Name:
CARINACXO
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This database table contains a catalog of >~ 14,000 X-ray sources observed by the ACIS instrument on the Chandra X-ray Observatory within a 1.42 deg<sup>2</sup> survey of the Great Nebula in Carina, known as the Chandra Carina Complex Project (CCCP). The study from which this table is taken appeared in a special ApJS issue which was devoted to the CCCP. In it, the authors described the data reduction and analysis procedures performed on the X-ray observations, including calibration and cleaning of the X-ray event data, point-source detection, and source extraction. The catalog appears to be complete across most of the field to an absorption-corrected total-band luminosity of ~ 10<sup>30.7</sup> erg s<sup>-1</sup> for a typical low-mass pre-main-sequence star. Counterparts to the X-ray sources were identified in a variety of visual, near-infrared, and mid-infrared surveys. The X-ray and infrared source properties presented herein form the basis of many CCCP studies of the young stellar populations in Carina. The prefixes 'fb', 'sb' and 'hb' on the names of photometric quantities designate the full or total (0.5-8 keV), soft (0.5-2 keV), and hard (2-8 keV) energy bands. Source significance quantities (fb_prob_no_src, sb_prob_no_src, hb_prob_no_src, prob_no_src_min) were computed using a subset of each source's extractions chosen to maximize significance (Broos et al. 2010, ApJ, 714, 1582, hereafter B10, Section 6.2). X-ray source position quantities (RA, Dec, error_radius) were computed using a subset of each source's extractions chosen to minimize the position uncertainty (B10, Sections 6.2 and 7.1). All other quantities were computed using a subset of each source's extractions chosen to balance the conflicting goals of minimizing photometric uncertainty and of avoiding photometric bias (B10, Sections 6.2 and 7). A summary of the counterpart catalogs that were correlated with the Chandra Carina sources is given in Table 5 of the reference paper and is listed below: <pre> Catalog Scope Reference Skiff Visual spectral types Skiff (2009, VizieR Online Data Catalog, 1, 2023) KR Visual photometry Kharchenko & Roeser (2009, VizieR Online Data Catalog, 1280, 0) PPMXL CCD proper motions (PMs) Roeser et al. (2010, AJ, 139, 2440) UCAC3 CCD PMs Zacharias et al. (2004, AJ, 127, 3043) BSS Bright star PMs Urban et al. (2004, VizieR Online Data Catalog, 1294, 0) CMD Photographic PMs, Tr 14, Tr 16, Cr 232 Cudworth et al. (1993, AJ, 105, 1822) DETWC Visual photometry, Tr 14 & 16 DeGioia-Eastwood et al. (2001, ApJ, 549, 578) MDW Visual spectral types, Cr 228 Massey et al. (2001, AJ, 121, 1050) MJ Visual photometry, Tr 14 & 16 Massey & Johnson (1993, AJ, 105, 980) CP High-mass photometry, Cr 228 Carraro & Patat (2001, A&A, 379, 136) DAY Low-mass photometry, Cr 228 Delgado et al. (2007, A&A, 467, 1397) HAWK-I Deep near-infrared photometry Preibisch et al. (2011, ApJS, 194, 10, CCCP HAWK-I Paper) 2MASS Shallow near-infrared photometry Skrutskie et al. (2006, AJ, 131, 1163) SOFI Deep near-infrared photometry, Tr 14 Ascenso et al. (2007, A&A, 476, 199) NACO Deep near-infrared photometry, Tr 14 Ascenso et al. (2007, A&A, 476, 199) Sana Deep near-infrared photometry, Tr 14 Sana et al. (2010, A&A, 515, A26) SpVela Mid-infrared photometry (Spitzer) Povich et al. (2011, ApJS, 194, 14, CCCP IR YSOs Paper) SpSmith Mid-infrared photometry (Spitzer) Smith et al. (2010, MNRAS, 406, 952) AC ACIS observation of Tr 16 Albacete-Colombo et al. (2008, A&A, 490, 1055) </pre> This table was created by the HEASARC in May 2011 based on the electronic versions of Tables 2 and 6 from the reference paper which were obtained from the ApJS web site. This is a service provided by NASA HEASARC .
5. Cataclysmic Variables Catalog (2006 Final Edition)
ID:
ivo://nasa.heasarc/cvcat
Title:
Cataclysmic Variables Catalog (2006 Final Edition)
Short Name:
CVs
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This catalog contains data for a large number of objects that have been classified as cataclysmic variables (CVs) as well as a smaller number of objects that are now not considered to be cataclysmic variables, but were originally classified erroneously as such. As of 2000 December, 40% of the objects in this catalog were dwarf novae, with another 30% being novae, and the rest being mostly nova-like variables; also as of this date, a large fraction (90%) of the CVs had references to published finding charts, while 64% of the objects had published spectra. The catalog includes coordinates measured in the reference frame of the Hubble Space Telescope Guide Star Survey for non-novae and from the literature for novae. Also given are the variability type, the magnitude range, orbital periods, flags indicating the existence of relevant space-based observational datsets, references to finding charts and spectroscopy, the galactic latitude and longitude, and the year of outburst (for novae). This edition also includes plate identification information for the coordinate measurements, and a reference to the classification. The Catalog and Atlas of Cataclysmic Variables (Downes et al. in 2001, PASP, 113, 764 and <a href="http://archive.stsci.edu/prepds/cvcat/">http://archive.stsci.edu/prepds/cvcat/</a>) presented here is the ASCII Report mentioned in Section 2.1 of the PASP paper, and is similar to the previously published versions of the CV Catalog (e.g., Downes, Webbink and Shara 1997, PASP, 109, 345, Table 1). The online version of the CV Catalog at <a href="http://archive.stsci.edu/prepds/cvcat/">http://archive.stsci.edu/prepds/cvcat/</a> contains additional data on these systems not included in this database, including finding charts. For a complete authoritative and up-to-date description of the CV Catalog, refer to <a href="http://archive.stsci.edu/prepds/cvcat/description.html">http://archive.stsci.edu/prepds/cvcat/description.html</a>, from which the HEASARC has constructed this help file. This HEASARC version of the CV Catalog was last updated in February 2006. This is a service provided by NASA HEASARC .
6. Catalog of Ap, HgMn and Am Stars
ID:
ivo://nasa.heasarc/cpstars
Title:
Catalog of Ap, HgMn and Am Stars
Short Name:
Ap/Am
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains a catalog of 8205 known or suspected Ap, HgMn and Am stars. This is a major update of the authors' first edition of their catalog of Ap and Am stars, and includes revised identifications, additional stars, and revised information obtained m the literature. This table was created by the HEASARC in July 2009 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/III/260">CDS Catalog III/260</a> file catalog.dat. It replaced an earlier version based on the 1st edition of the Ap and Am Stars Catalog (Renson et al. 1991). This is a service provided by NASA HEASARC .
7. Catalog of Galactic OB Stars
ID:
ivo://nasa.heasarc/galobstars
Title:
Catalog of Galactic OB Stars
Short Name:
GALOBSTARS
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
An all-sky catalog of Galactic OB stars has been created by extending the Case-Hamburg Galactic Plane Luminous Stars surveys to include 5,500 additional objects drawn from the literature. This work brings the total number of known or reasonably suspected OB stars to over 16,000. This catalog contains UBV photometry and MK spectral type classifications for these objects as well as radial velocities. This project originated in the summer of 1991 when the author began compiling a cross-reference catalog and tabulation of published UBVbeta photometry for stars listed in Stephenson and Sanduleak's Luminous Stars (LS) in the Southern Milky Way Catalog (<a href="https://cdsarc.cds.unistra.fr/ftp/cats/III/43">CDS Cat. III/43</a>). This database was published in July 1993 (Reed 1993, ApJS, 87, 367) and was subsequently expanded to include compilations of published MK classifications (Reed & Beatty 1995, ApJS, 97, 189), 4-color photometry (Read 1996, A&AS, 117, 313), and radial velocities (Reed & Kuhna 1997, AJ, 113, 823) for these objects. In mid-1997 the project was again expanded to include UBVbeta photometry for stars listed in the Northern-hemisphere volumes of the "Case-Hamburg" (<a href="https://cdsarc.cds.unistra.fr/ftp/cats/III/76">CDS Cat. III/76</a>) surveys (Reed 1998, ApJS, 115, 271); MK classifications for the Northern stars were similarly compiled and made electronically available to interested parties, though they were not formally published. Most of the LS objects are OB stars, but there are as well a number of A, F, and G supergiants and a few white dwarfs and Wolf Rayet stars. These surveys reached a limiting photographic magnitude of ~13.5, and were based on objective-prism surveys of dispersion 580 Angstrom/mm at H-gamma. OB stars is here taken to mean main-sequence stars down to temperature class B2 and more luminous ones down to temperature class B9. The original Case-Hamburg surveys (about 12,000 stars) also include some 2,000 evolved A-G stars, along with some white dwarfs, planetary nebulae, and Wolf-Rayet stars. It is worth noting that the definition of an OB star is not universal; for example, Vanbeveren et al. (1998, in "The Brightest Stars") define them as O-B2 V-IV, O-B3 III, O-B4 II, and all OBA Ib, Iab, Ia, and IaO stars. This table was created by the HEASARC in September 2017 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/V/125">CDS Catalog V/125</a> files obcat.dat, obmk.dat, obubvbet.dat and radvel.dat. This is a service provided by NASA HEASARC .
8. Catalog of High-Mass X-Ray Binaries in the Galaxy (4th Ed.)
ID:
ivo://nasa.heasarc/hmxbcat
Title:
Catalog of High-Mass X-Ray Binaries in the Galaxy (4th Ed.)
Short Name:
HM XRB
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains the 4th edition of the Catalog of High-Mass X-Ray Binaries (HMXBs) in the Galaxy. The catalog contains source name(s), coordinates, finding charts, X-ray luminosities, system parameters, and stellar parameters of the components and other characteristic properties for 114 HMXBs, together with a comprehensive selection of the relevant literature. The aim of this catalog is to provide some basic information on the X-ray sources and their counterparts in other wavelength ranges (gamma-rays, UV, optical, IR, radio). About 60% of the high-mass X-ray binary candidates are known or suspected Be/X-ray binaries, while 32% are supergiant/X-ray binaries. Some sources, however, are only tentatively identified as high-mass X-ray binaries on the basis of their X-ray properties similar to the known high-mass X-ray binaries. Further identification in other wavelength bands is needed to finally determine the nature of these sources. In cases where there is some doubt about the high-mass nature of the X-ray binary this is noted. Literature published before 1 October 2005 has, as far as possible, been taken into account. Information on the numbers used to code references is available at the URL <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/455/1165/refs.dat">https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/455/1165/refs.dat</a> Individual notes on each HMXB are available at the URL <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/455/1165/notes.dat">https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/455/1165/notes.dat</a> This database was first created by the HEASARC in January 2001, based on the 2000 version of this catalog. It was updated to the 4th edition in September 2006, based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/455/1165">CDS catalog J/A+A/455/1165</a>. This is a service provided by NASA HEASARC .
9. CoRoT Stellar Targets for Exoplanet Detection Observation Log
ID:
ivo://nasa.heasarc/corotexlog
Title:
CoRoT Stellar Targets for Exoplanet Detection Observation Log
Short Name:
COROTEXLOG
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
CoRoT was a space astronomy mission devoted to the study of the variability with time of stars' brightness, with an extremely high accuracy (100 times better than from the ground), for very long durations (up to 150 days) and with a very high duty cycle (more than 90%). The mission was led by CNES in association with four French laboratories, and 7 participating countries and agencies (Austria, Belgium, Brazil, Germany, Spain, and the ESA Science Programme). The satellite is composed of a PROTEUS platform (the 3rd in the series), and a unique instrument: a stellar photometer. It was launched on December 27th, 2006 on a Soyuz Rocket, from Baikonour. The mission has lasted almost 6 years (the nominal 3 years duration and a 3 years extension) and has observed more than 160,000 stars. It suddenly stopped sending data on November 2nd, 2012. CoRoT performed Ultra High Precision Photometry of Stars to detect and characterize the variability of their luminosity with two main objectives: (i) the variability of the object itself: oscillations, rotation, magnetic activity, etc.; (ii) variability due to external causes such as bodies in orbit around the star: planets and companion stars. The original scientific objectives were focused on the study of stellar pulsations (asteroseismology) to probe the internal structure of stars, and the detection of small exoplanets through their transit in front of their host star, and the measurement of their sizes. This lead to the introduction of two modes of observations, working simultaneously: - The bright star mode dedicated to very precise seismology of a small sample (171) of bright and nearby stars (presented in the file named "Bright_star.dat" in the CDS version at <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/corot/">https://cdsarc.cds.unistra.fr/ftp/cats/B/corot/</a>): these data are not included in this HEASARC table, notice; - The faint star mode, observing a very large number of stars at the same time, to detect transits, which are rare events, as they imply the alignment of the star, the planet and the observer (these data are presented in the file named "Faint_star.dat" in the CDS version at <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/corot/">https://cdsarc.cds.unistra.fr/ftp/cats/B/corot/</a>): this HEASARC table is based on this sample. The large amount of data gathered in this mode mode turned out to be extremely fruitful for many topics of stellar physics. Due to project constraints, two regions of the sky were accessible (circles of 10 degrees centered on the equator around Right Ascensions of 06<sup>h</sup> 50<sup>m</sup> and 18<sup>h</sup> 50<sup>m</sup>). They are called the CoRoT 'eyes': the first one is called the "anticenter" eye, whereas the second one is called the "center eye". Each pointing covers 1.4 x 2.8 square degrees. The CoRoT project is still processing the data, aiming at removing instrumental artifacts and defects. Therefore the format and content of the catalog is still somewhat evolving. More details on the data can be found in the file <a href="http://idoc-corotn2-public.ias.u-psud.fr/jsp/doc/CoRoT_N2_versions_30sept2014.pdf">http://idoc-corotn2-public.ias.u-psud.fr/jsp/doc/CoRoT_N2_versions_30sept2014.pdf</a>. More details on the CoRoT N2 data may be found in the documentation file <a href="http://idoc-corotn2-public.ias.u-psud.fr/jsp/doc/DescriptionN2v1.5.pdf">http://idoc-corotn2-public.ias.u-psud.fr/jsp/doc/DescriptionN2v1.5.pdf</a>. This HEASARC table contains information on stars observed by CoRoT in its exoplanet detection program. A few percent of these stars have 2 entries since they were observed in different windows (as specified by the corot_window_id parameter) in a subsequent observing run to the initial run in which they were observed. Each entry in this table corresponds to the unique specification of target and corot_window_id, each with a link to its associated N2 data products. The original names of the parameters in this table, as given in the CoRoT mission documentation, are given in square brackets at the end of the parameter descriptions listed below. This table was created by the HEASARC in May 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/corot">CDS Catalog B/corot</a> file Faint_star.dat. The HEASARC routinely updates this table after updates are made to the CDS version of this catalog. This is a service provided by NASA HEASARC .
10. Dynamical Masses of Selected Orbital Binary Systems
ID:
ivo://nasa.heasarc/morbbincat
Title:
Dynamical Masses of Selected Orbital Binary Systems
Short Name:
MORBBINCAT
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
Orbital binary stars are essential objects for determining dynamical and physical properties of stars through a combined analysis of photometric and astrometric data. The authors have compiled a set of orbital binaries with known trigonometric parallaxes and orbits of high quality, using data from current versions of the Observatorio Astronomico Ramon Maria Aller Catalog (OARMAC) of Orbits and Ephemerides of Visual Double Stars (Docobo et al. 2001, AcA, 51, 353) and the Sixth Catalog of Orbits of Visual Binary Stars (ORB6: Mason and Hartkopf 2007, IAUS 240, 575; Hartkopf et al. 2001, AJ, 122, 3472), as well as including updated information from the Washington Double Star (WDS) Catalog and SIMBAD. They constructed distributions of orbital binaries of the dynamical mass, period, semi-major axis, and eccentricity of systems, which characterize the set. Some problems related to the parametrization of orbital binaries are also discussed in the paper. To compile the orbit list, the authors combined data from both OARMAC and ORB6. At this stage, they maintained systems without parallaxes, but removed systems without a period or semi-major axis. The resulting list contained 3139 orbits for 2278 pairs: 1588 pairs have a single orbit, 548 pairs have two orbits, 120 pairs have three orbits, 19 pairs have four orbits, one pair has five orbits, and two pairs have seven orbits. Table 1 in the reference paper (not part of this HEASARC table) contains a compiled set of 3139 orbit solutions for visual binary stars. Separate entries are provided for different pairs in multiple systems. Several solutions per pair are possible. Each entry includes main orbital elements (Semi-major axis, period, eccentricity with corresponding uncertainties), indication of multiplicity and number of solutions, as well as visual magnitudes, spectral classes of the components, parallax and interstellar extinction estimate. Table 2 in the reference paper (on which this HEASARC table is based) contains a refined set of 652 solely binary systems with reliable orbits and determined parallaxes. One entry in this table corresponds to one system. Three mass estimates are provided: (1) The dynamical mass with its uncertainty derived from Kepler's third law and its trigonometric parallax, (2) a photometric mass estimated from the visual magnitudes, parallax and mass-luminosity relation, and (3) a spectroscopic mass based on the mass-spectrum relation introduced by Straizys and Kuriliene (1981, Ap&SS, 80, 353). Also provided for each system are the main orbital elements, the parallax, and the component magnitudes and spectral types. This table was created by the HEASARC in October 2014 based on the list of orbital binaries given in <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/546/A69">CDS Catalog J/A+A/546/A69</a> file table2.dat. Note that this table does not include the information on individual orbits which given listed in file table1.dat of this CDS catalog. This is a service provided by NASA HEASARC .

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