ABSTRACT We present a purely differential line-of-sight distance between M31 and M33 using ab-type RR Lyrae variables observed in each galaxy by the Hubble Space Telescope Advanced Camera for Surveys F606W filter. Using 1481 Lyraes 13 fields 181 6 fields, placing all of these stars on uniform photometric scale with internally consistent corrections metal abundance extinction, we find relative a...

Amajor uncertainty in the dynamical history of the local group of galaxies originates from the unknown transverse speed of the Andromeda galaxy (M31) relative to the Milky Way. We show that the recent VLBA measurement of the proper motion of Andromeda’s satellite, M33, severely constrains the possible values of M31’s proper motion. The condition that M33’s stellar disk will not be tidally disru...

In Drosophila and mouse, Polycomb group genes are involved in the maintenance of homeotic gene expression patterns throughout development. Here we report the skeletal phenotypes of compound mutants for two Polycomb group genes bmi1 and M33. We show that mice deficient for both bmi1 and M33 present stronger homeotic transformations of the axial skeleton as compared to each single Polycomb group ...

I suggest that the bulk of the ”young”, second-parameter globular clusters (SPGCs) observed in the outer halo of our Galaxy and recently found in other massive spiral of the Local Group (LG), M33, may have originated due to mass outflow from M31 and subsequent accretion of gas on the Galaxy and M33 in the early epoch. 1. Problem and Main Questions There are contradictory conclusions about the d...

We have obtained 12 CO and 13 CO J=1-0 observations of the nearby spiral galaxy M33 to try to resolve the long-standing discrepancy between 12 CO/ 13 CO line ratios measured in Galactic giant molecular clouds and external galaxies. Interferometer maps of the molecular cloud MC20 give a 12 CO/ 13 CO line ratio of 7:52:1, which agrees reasonably well with the line ratio measured in Galactic giant...

We undertook a long term project, DIRECT, to obtain the direct distances to two important galaxies in the cosmological distance ladder – M31 and M33 – using detached eclipsing binaries (DEBs) and Cepheids. While rare and difficult to detect, DEBs provide us with the potential to determine these distances with an accuracy better than 5%. The extensive photometry obtained in order to detect DEBs ...

Abstract The dust extinction curves toward individual sight lines in M33 are derived for the first time with a sample of reddened O-type and B-type supergiants obtained from Local Group Galaxies Survey (LGGS). observed photometric data LGGS, PS1 Survey, UKIRT, PHATTER Galaxy Evolution Explorer, Swift/UVOT, XMM-SUSS. We combine intrinsic spectral energy distributions (SEDs) ATLAS9 Tlusty stellar...