733 datasets found

We present BVRI photometry of the low metallicity globular cluster M68 (NGC 4590) observed with a CCD camera and the 2.2m telescope at ESO/La Silla, and have compared our BV...

B and V band CCD photometry is used to study 33 cluster and nine field RR Lyrae variables near the LMC cluster, NGC 2257. It is found that the mean magnitudes for the two groups...

Using CCD UBV photometry and spectroscopy, we have investigated the stellar content of NGC 346, the brightest H II region in the SMC. Spectra of 42 stars confirm that 33 are of...

We present broadband B,V photometry for 1154 stars in the field of the Galactic globular cluster Palomar 12, based upon direct CCD images obtained with the Canada-France-Hawaii...

We present new CCD photometry for the globular cluster M55 that extends well below the main-sequence turnoff. Combining these new data with previously published photographic...

We have constructed a color-magnitude diagram of the Ursa Minor dwarf spheroidal to m_V_=24.8mag from charged-coupled device (CCD) observations with the Kitt Peak 4 m telescope....

HS Hydrae is a short period eclipsing binary (Porb=1.57day) that belongs to a rare group of systems observed to have rapidly changing inclinations. This evolution is due to a...

V473Lyr is a classical Cepheid that is unique in having substantial amplitude variations with a period of approximately 3.3yr, thought to be similar to the Blazhko variations in...

We give the results of CCD observations for 789 double or multiple stars obtained during 2017 and 2018. These observations were carried out at both the Serbian Astronomical...

The unique binary AR Scorpii consists of an asynchronously rotating, magnetized white dwarf (WD) that interacts with its red-dwarf companion to produce a large-amplitude, highly...

The results of classical CCD observations for 371 double or multiple stars (450 pairs) obtained at both, Serbian Astronomical Station on the mountain of Vidojevica (ASV) and...

Proxima Centauri is known as the closest star to the Sun. Recently, radial velocity (RV) observations revealed the existence of an Earth-mass planet around it. With an orbital...

We report the discovery of a new ultra-short-period planet and summarize the properties of all such planets for which the mass and radius have been measured. The new planet,...

Results of CCD observations of 154 double or multiple stars, made with the 2 m telescope of the Bulgarian National Astronomical Observatory at Rozhen over five nights in 2015,...

Precise and accurate CCD-based UBVRI photometry is presented for ~2000 stars distributed around the sky in a declination zone centered approximately at +50{deg}. Their...

Precision uvbyCaH{beta} photometry of the metal-deficient, old open cluster NGC2506 is presented. The survey covers an area of 20'*20' and extends to V~18 for b-y and H{beta}...

Precision uvbyCaH{beta} photometry of the nearby old open cluster, NGC752, is presented. The mosaic of CCD fields covers an area ~42' on a side with internal precision at the...

In this paper, new CCD photometric observations of V508 Oph obtained in 2009 and 2010 at the Xinglong Observatory are presented. From the new observations, six new times of...

IM Per is a detached A7 eccentric eclipsing binary star. We have obtained extensive measurements of the light curve (28225 differential magnitude observations) and radial...

New CCD photometry is presented for the hot overcontact binary DK Cyg together with reasonable explanations for the light and period variations. Historical light and velocity...