Related papers: The distance to the Andromeda Galaxy from eclipsin…
We use masses, radii, and luminosities of the detached eclipsing binary OGLEGC17 derived from photometric and spectroscopic observations to calculate the age and distance of the globular cluster omega Cen. Age versus turnoff mass and age…
We demonstrate the presence of an extended and massive circumgalactic medium (CGM) around Messier 31 using archival HST COS ultraviolet spectroscopy of 18 QSOs projected within two virial radii of M31 (Rvir=300 kpc). We detect absorption…
The correlation between the luminosities and rotation velocities of galaxies can be used to estimate distances to late-type galaxies. It is an appropriate moment to re-evaluate this method given the great deal of new information available.…
We present the physical parameters of an eclipsing binary system EPIC 211982753 derived through photometric and radial velocity data modeling. We make use of photometric data from NASA's K2 mission, ASAS-SN, and 1.3-m Devasthal Fast Optical…
By correcting the redshift--dependent distances for peculiar motions through a number of peculiar velocity field models, we recover the true distances of a wide, all-sky sample of nearby galaxies (~ 6400 galaxies with velocities cz<5500…
We present the latest results from our project to search for new planetary nebulae in nearby galaxies using Sloan Digital Sky Survey (SDSS) imaging data. Our method is based on photometric criteria and can be applied to galaxies where PNe…
Identifying X-ray binary (XRB) candidates in nearby galaxies requires distinguishing them from possible contaminants including foreground stars and background active galactic nuclei. This work investigates the use of supervised machine…
AP And is a well-detached F5 eclipsing binary star for which only a very limited amount of information was available before this publication. We have obtained very extensive measurements of the light curve (19097 differential V magnitude…
The relation between the central mass and quasar luminosity (M_BH \propto L^{\alpha}FHWM^2) links a given Eddington ratio with a value of H_0, within a cosmology with fixed (\Omega_m,\Omega_{\Lambda}). We point out that because the relation…
Distances to stars are key to revealing a three-dimensional view of the Milky Way, yet their determination is a major challenge in astronomy. Whilst the brightest nearby stars benefit from direct parallax measurements, fainter stars are…
Photometry in B, V (down to V ~ 26 mag) is presented for two 23' x 23' fields of the Andromeda galaxy (M31) that were observed with the blue channel camera of the Large Binocular Telescope during the Science Demonstration Time. Each field…
We have used the Advanced Camera for Surveys on board the Hubble Space Telescope to obtain deep photometry of the NGC 300 spiral galaxy in the Sculptor group. The results have been used to derive an accurate distance determination based on…
Overview of the determination of astronomical distances from a metrological standpoint. Distances are considered from the Solar System (planetary distances) to extragalactic distances, with a special emphasis on the fundamental step of the…
Over the past decade, studies of dust in the Andromeda galaxy (M31) have shown radial variations in the dust emissivity index ($\beta$). Understanding the astrophysical reasons behind these radial variations may give clues about the…
We present a 900 sec, wide-field U image of the inner region of the Andromeda galaxy obtained during the commissioning of the blue channel of the Large Binocular Camera mounted on the prime focus of the Large Binocular Telescope. Relative…
The present status of the distance scale to Galactic globular clusters is reviewed. Six distance determination techniques which are deemed to be most reliable are discussed in depth. These different techniques are used to calibrate the…
A most desirable feature of a standard candle to estimate astronomical distances is robustness against changes in metallicity and age. It is argued that the radii of main sequence stars with spectral types from solar to A0 show predictable…
The unusual morphology of the Andromeda Spiral (Messier 31, the closest spiral galaxy to the Milky Way) has long been an enigma. Although regarded for decades as showing little evidence of a violent history, M~31 has a well-known outer ring…
The Andromeda Galaxy Stellar Robotic Microlensing Project (The Angstrom Project) aims to use stellar microlensing events to trace the structure and composition of the inner regions of the Andromeda Galaxy (M31). We present microlensing rate…
New estimate of the distances of 36 nearby galaxies is presented. It is based on the calibration of the V- and I-band Period-Lumi- nosity relations for galactic Cepheids measured by the HIPPARCOS mission. The distance moduli are obtained in…