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In this paper, we present our results for the photometric and kinematical studies of old open cluster NGC 188. We determined various astrophysical parameters like limited radius, core and tidal radii, distance, luminosity and mass functions, total mass, relaxation time etc. for the cluster using 2MASS catalog. We obtained the cluster's distance from the Sun as 1721±41 pc and log (age)= 9.85±0.05 at Solar metallicity. The relaxation time of the cluster is smaller than the estimated cluster age which suggests that the cluster is dynamically relaxed. Our results agree with the values mentioned in the literature. We also determined the clusters apex coordinates as (281• .88, −44• .76) using AD-diagram method. Other kinematical parameters like space velocity components, cluster center and elements of Solar motion etc. have also been computed.

ABSTRACT:In this paper, we are going to introduce the Kottamia Astronomical Observatory, KAO, to the astronomical community. The current status of the telescope together with the available instrumentations is described. An upgrade stage including a new optical system and a computer controlling of both the telescope and dome are achieved. The specifications of a set of CCD cameras for direct imaging and spectroscopy are given. A grating spectrograph is recently gifted to KAO from Okayama Astrophysical Observatory, OAO, of the National Astronomical Observatories in Japan. This spectrograph is successfully tested and installed at the F/18 Cassegrain focus of the KAO 74" telescope.

We present a photometric study for three rarely studied open star clusters; Juchert-Saloranta 1, Teutsch 1 and Teutsch 5 using the 2MASS-JHKs photometric data. Their structural and photometric parameters are determined. We obtained the distance from the Sun of 3.30 ± 0.30 kpc, 3.82 ± 0.25 kpc and 2.91 ± 0.34 kpc and their log(age) of 9.15, 8.75 and 8.9 at solar metallicity and the total mass of 215, 807 and 165 M for Juchert-Saloranta 1, Teutsch 1 and Teutsch 5 respectively. The three clusters lie in the galactic plane and about 11 kpc from the galactic center. The relaxation times of the clusters are smaller than the estimated cluster ages (∼ 0.01) that may be reflect the dynamical relaxation of these clusters.