Related papers: The Distance to M104
We recently inferred that the galaxy NGC1052-DF2 has little or no dark matter and a rich system of unusual globular clusters. We assumed that the galaxy is a satellite of the luminous elliptical galaxy NGC1052 at ~20 Mpc, on the basis of…
We report a new geometric maser distance estimate to the active galaxy NGC 4258. The data for the new model are maser line-of-sight velocities and sky positions from 18 epochs of Very Long Baseline Interferometry observations, and…
Measurements of the linear diameters of 12 nearby spiral galaxies with distances determined from primary indicators suggest that both the Milky Way Galaxy and M31 are in the middle of the range of sizes for such galaxies. By comparing the…
We consider the application of the tip of the red giant branch (TRGB) in the optical and in the near infrared for the determination of distances to nearby galaxies. We analyze ACS VI (F555W & F814W) data and self-consistently…
We present final results of a program for the determination of the Hubble constant based on the calibration of the Type Ia supernovae (SNe Ia) using the Tip of the Red Giant Branch (TRGB). We report TRGB distances to three SN Ia host…
In the present paper we develop an algorithm allowing to calculate line-of-sight velocity dispersions in an axisymmetric galaxy outside of the galactic plane. When constructing a self-consistent model, we take into account the galactic…
We present preliminary results of 2dF spectroscopy of globular clusters in The Sombrero (M104). We find 56 new clusters, and compile a total sample of 103 velocities combined with previous data. Our 2dF data extend out to 20 arcmin radius…
We present results from deep, wide-field surface photometry of three nearby (D=4--7 Mpc) spiral galaxies: M94 (NGC 4736), M64 (NGC 4826), and M106 (NGC 4258). Our imaging reaches limiting surface brightnesses of $\mu_{B} \sim$ 28 -- 30 mag…
Differences between the local value of the Hubble constant measured via the distance ladder versus the value inferred from the cosmic microwave background with the assumption of the standard $\Lambda$CDM model have reached over 5$\sigma$…
We present a new study of late-type eclipsing binary stars in the Small Magellanic Cloud (SMC) undertaken with the aim of improving the distance determination to this important galaxy. A sample of 10 new detached, double-lined eclipsing…
We present near-infrared J- and K-band photometry of 77 Cepheid variables in the Local Group galaxy NGC 3109. Combining our data with the previously published optical V- and I-band photometry of Cepheids in this galaxy we derive an accurate…
We report the results of an [O III] lambda 5007 survey for planetary nebulae (PN) in three spiral galaxies: M101 (NGC 5457), M51 (NGC 5194/5195) and M96 (NGC 3368). By comparing on-band/off-band [O III] lambda 5007 images with images taken…
Thanks to the outstanding capabilites of the HST, our current knowledge about the M31 globular clusters (GCs) is similar to our knowledge of the Milky Way GCs in the 1960s-1970s, which set the basis for studying the halo and galaxy…
A measurement of the distance to Virgo Cluster by a direct method along with a realistic error analysis is important for a reliable determination of the value of Hubble Constant. Cepheid variables in the face-on spiral M100 in the Virgo…
Molecular gas plays a critical role in explaining the quiescence of star formation (SF) in massive isolated spiral galaxies, which could be a result of either the low molecular gas content and/or the low SF efficiency. We present IRAM 30m…
The theoretical evaluations of the Red Giant Branch Tip (TRGB) luminosity presented in Salaris & Cassisi (1997) are extended to higher metallicities, and compared with analogous independent results recently published. The comparison between…
We present a new approach for identifying the Tip of the Red Giant Branch (TRGB) which, as we show, works robustly even on sparsely populated targets. Moreover, the approach is highly adaptable to the available data for the stellar…
We report on a first application of the infrared surface brightness technique on a Cepheid in the Large Magellanic Cloud, the variable HV 12198 in the young globular cluster NGC 1866. From this one star, we determine a distance modulus of…
We report redshifts, magnitudes and morphological classifications for 5369 galaxies with $m_B \leq 15.5$ and 57 galaxies fainter than this limit, in two regions covering a total of 1.70 steradians in the southern celestial hemisphere. The…
The results of the stellar photometry of the images ACS/WFC and WFPC2 of the HST are used to study stellar population and spatial distribution of stars in three edge-on galaxies: NGC 891, NGC 4144 and NGC 4244. The measuring of the number…