77 datasets found

URAT1 is an observational catalog at a mean epoch between 2012.3 and 2014.6; ot covers the magnitude range 3 to 18.5 in R-band, with a positional precision of 5 to 40 mas. It...

The Second Byurakan Survey (SBS) General Catalogue is presented. The SBS, a continuation of the Markarian survey reaching fainter limiting magnitudes, is the first survey which...

We present photographic UBV photometry of the blazar 3C 345 that were made during 79 nights in 1971-1974 and 1983-1984 as a part of the Petersburg Quasar Monitoring Program...

The study presents photoelectric photometry of stars in NGC 5822 on the UBVR and DDO systems. The BV data are employed to calibrate a photographic survey of the cluster, while...

The Milky Way galaxy contains a large, spherical component which is believed to harbor a substantial amount of unseen matter. Recent observations indirectly suggest that as much...

A new method for combined calculations of magnitudes based on accurate measurements of POSS1 and POSS2 epoch plates is given. The photometric accuracy of various surveys and...

We selected from the VLA FIRST survey a sample of 94 objects with star-like counterparts in the Sloan Digital Sky Survey (SDSS), and with APM POSS-I colour O-E>=2, i.e....

Large-scale astrometric and photometric data bases have been used to search for and confirm stellar membership of the open cluster IC 2391. 125 stars were found that satisfied...

Digitized UK Schmidt plate photometry, calibrated with CCD photometry, is obtained in 18 regions over the Bulge. Stars are selected for spectroscopic follow-up from with a...

Photoelectric and photographic photometry of the open cluster Melotte 66 is presented. The CM diagram shows most of the characteristics of an old cluster. The giant branch is...

Results of long-term monitoring of the quasar 3C345 from 1984 to 1991 are presented. Observations has been conducted on the Byurakanskii station of the St. Petersburg...

We present trigonometric, photometric, and photographic distances to 1748 southern ({delta}{<=}O{deg}) M dwarf systems with {mu}>=0.18''/yr, of which 1404 are believed to...

We present the historic photographic light curves of three little known blazars (two BL Lac objects and one FSRQ), GB6 J1058+5628, GB6 J1148+5254, and GB6 J1209+4119, spanning a...

We use Hubble Space Telescope (HST) Faint Object Camera (FOC) ultraviolet (UV) and WFPC2 optical images in conjunction with UV spectroscopic observations taken with the Goddard...

We have begun a search for early-type stars towards the galactic centre which are potentially young objects situated within the inner few kiloparsecs of the disk. U and V (or I)...

In current astronomical surveys with ever-increasing data volumes, automated methods are essential. Objects of known classes from the literature are necessary to train...

The star V426 Sge (HBHA 1704-05), originally classified as an emission-line object and a semi-regular variable, brightened at the beginning of August 2018, showing signatures of...

A set of 55000 stars brighter than about B-magnitude 14 and having at least three observations are identified in the Sydney Observatory Galactic Survey, carried out over the...

RR Gem is one of the few Blazhko RR Lyrae which has extended enough photometric observations available to study the long-term courses of its pulsation and modulation properties...

The results of a complex study of the galactic open cluster Trumpler 2 are presented. In order to obtain the proper motions, the positions of approximately 3000 stars up to the...