Садржај
Слике
Уплоадјуј своје слике
DSS Images Other Images
Везани чланци
Two Active Nuclei in 3C 294
The z=1.786 radio galaxy 3C 294 lies < 10" from a 12 mag star and hasbeen the target of at least three previous investigations using adaptiveoptics (AO) imaging. A major problem in interpreting these results isthe uncertainty in the precise alignment of the radio structure with theH- or K-band AO imaging. Here we report observations of the position ofthe AO guide star with the Hubble Space Telescope Fine Guidance Sensor,which, together with positions from the second United States NavalObservatory's CCD Astrograph Catalog (UCAC2), allow us to register theinfrared and radio frames to an accuracy of better than 0.1". The resultis that the nuclear compact radio source is not coincident with thebrightest discrete object in the AO image, an essentially unresolvedsource on the eastern side of the light distribution, as Quirrenbach andcoworkers had suggested. Instead, the radio source is centered about0.9" to the west of this object, on one of the two apparently real peaksin a region of diffuse emission. Nevertheless, the conclusion ofQuirrenbach and coworkers that 3C 294 involves an ongoing merger appearsto be correct: analysis of a recent deep Chandra image of 3C 294obtained from the archive shows that the nucleus comprises two X-raysources, which are coincident with the radio nucleus and the easternstellar object. The X-ray/optical flux ratio of the latter makes itextremely unlikely that it is a foreground Galactic star.Based in part on observations made with the NASA/ESA Hubble SpaceTelescope, obtained at the Space Telescope Science Institute, which isoperated by the Association of Universities for Research in Astronomy(AURA), Inc., under NASA contract NAS5-26555. These observations areassociated with proposal 08315. Based in part on data collected atSubaru Telescope, which is operated by the National AstronomicalObservatory of Japan. Some of the data presented herein were obtained atthe W. M. Keck Observatory, which is operated as a scientificpartnership among the California Institute of Technology, the Universityof California and the National Aeronautics and Space Administration. TheObservatory was made possible by the generous financial support of theW. M. Keck Foundation. Some of the data were also obtained from theChandra Data Archive, part of the Chandra X-Ray Observatory ScienceCenter, which is operated for NASA by the Smithsonian AstrophysicalObservatory.
| CCD photometry and astrometry of visual double and multiple stars of the HIPPARCOS Catalogue. II. CCD photometry and differential astrometry of 288 southern ``Intermediate'' systems
We present photometric and astrometric data of about 280 visual doublestars of the ``intermediate'' class, i.e. with angular separationsmainly in the range 2arcsec < rho < 12arcsec . The observationshave been obtained in 1991-92 with a CCD camera attached to the 91 cmDutch telescope at ESO La Silla, Chile. Differential magnitudes of thedouble star components as well as magnitudes and colour indices of theindividual components have been determined in the Cousins V and Ipassbands with an internal error of about 0.005 mag and an externalaccuracy of less than 0.03 mag. In addition, angular separations havebeen secured to an internal accuracy of 0.004arcsec and position anglesto about 0.05degr. Tables 1 to 4 are only available in electronic format the CDS via ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html. Based on observationscollected at the European Southern Observatory, La Silla, Chile.
| A second list of wide visual binaries
Not Available
| A second list of wide visual binaries
Not Available
| Common proper motion stars in the AGK 3
A search was made of common-proper-motion (CPM) systems among AGK 3stars. The selection of physical systems was based upon the ratiobetween the angular separation (rho) and the proper motion (mu); the CPMstars found are presented in two tables. Table I lists systems withrho/mu less than 1000 years. It contains 326 entries, and the proportionof optical pairs is estimated to be 1 percent. Table II lists systemswith rho/mu in the range 1000 to 3500 years; it contains 113 systems,but only 60 percent of them are physical. Nevertheless, these systemsoften have separations larger than 10,000 AU and are the mostinteresting for the study of the tail of the distribution function ofthe semimajor axes.
| A list of stars with common proper motions.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958AJ.....63..246V&db_key=AST
|
Додај нови чланак
Линкови у сродству са темом
Додај нови линк
Чланови следећих група \:
|
Посматрања и Астрометриски подаци
| Сазвежђа: | Девица |
| Ректацензија: | 13h02m07.87s |
| Deклинација: | +07°16'47.0" |
| Apparent магнитуда: | 9.19 |
| Proper motion RA: | -124.8 |
| Proper motion Dec: | 17.8 |
| B-T magnitude: | 9.716 |
| V-T magnitude: | 9.234 |
Каталог и designations:
|
