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FSR19 and FSR25 confirmed as two new faint and metal-rich globular clusters in the galactic bulge
Minniti, D.; Alonso-García, J.; Gómez, M. +1 more
We combined the near-IR photometry from the VISTA Variables in the Vía Láctea extended Survey (VVVX) with Gaia EDR3 catalog to study some properties of FSR19 and FSR25. These are confirmed to be low luminosity metal-rich bulge globular clusters (Obasi et al. 2020). The proper motions (PM) remain unchanged and the Color magnitude diagrams (CMD) are…
Calibration Techniques for Studying Venus and Mars Atmospheres
Gramigna, Edoardo
The European Space Agency Venus Express mission (VEX) was sent to Venus in 2005 to unveil the unsolved mysteries regarding its atmosphere, the plasma environment and its temperatures. Radio occultation experiments performed by VeRa radio science instrument probed the planet's atmosphere by studying the frequency shift on the radio signal sent by t…
Latitude observations of the last century to obtain accurate independent latitude stations (INDLS) catalog of µδ for 682 Hipparcos stars and comparison with Gaia DR2
Damljanović, Goran
The independent latitude stations (INDLS) catalog of proper motion in declination µδ for 682 bright Hipparcos (HIP) stars is presented. It is obtained in the Hipparcos reference frame, and only the Hipparcos mean position at epoch 1991.25 is used for INDLS data to calculate independent µδ (the HIP µδ values are not included in th…
Seeing the Bigger Picture: Rosetta Mission Amateur Observing Campaign and Lessons for the Future
Roche, Paul; Norton, Andrew; Snodgrass, Colin +2 more
Amateur astronomers can make useful contributions to the study of comets. They add temporal coverage and multiscale observations that can aid the study of fast-changing and large-scale comet features. We document and review the amateur observing campaign set up to complement the Rosetta space mission, including the data submitted to date, and cons…
A New Candidate Luminous Blue Variable
Menten, Karl M.; Figer, Donald F.; Messineo, Maria +2 more
We identify IRAS 16115-5044, which was previously classified as a protoplanetary nebula (PPN), as a candidate luminous blue variable (LBV). The star has high luminosity (≳105.75 L⊙), ensuring supergiant status, has a temperature similar to LBVs, is photometrically and spectroscopically variable, and is surrounded by warm dust…
Influence of the convective mixing-length parameter α on the chemical abundances in the case of metal-poor giant HD 122563
Zhao, Gang; Song, Nan; Alexeeva, Sofya
One-dimensional (1D) model atmospheres are still the most commonly used tool for the determination of stellar chemical composition. Convection in the model is usually treated by mixing-length theory (MLT). The mixing-length parameter α is generally calibrated from the Sun and applied to all other stars. The metal-poor giant, HD 122563, is an impor…
Sources of Bipolar Outflows and Model Challenges for the Egg Nebula
Ohyama, Youichi; Lim, Jeremy; Dinh-V-Trung
The striking features of the Egg Nebula—searchlight beams that illuminate a pair of bipolar lobes, quadrupolar outflows, and arcs imprinted on an expanding spherical envelope—have long defied a coherent explanation. Here we present images at high angular resolutions of emission from dust and dense molecular gas in the nebula. Away from the systemi…
A photometric study of HAT 141-03513: another twin of the V361 Lyr system
Wolf, M.; Kučáková, H.
The BVRI light curves were measured for the eclipsing binary HAT 141-03513 as a part of our long-term observational project for studying low-mass eclipsing binaries with a short orbital period. The asymmetric light curve and the difference in brightness in maxima, are probably the result of presence of a hot region on the surface of one component.…
X-ray study of the double source plane gravitational lens system Eye of Horus observed with XMM-Newton
Lee, Chien-Hsiu; Sonnenfeld, Alessandro; Oguri, Masamune +19 more
A double source plane (DSP) system is a precious probe for the density profile of distant galaxies and cosmological parameters. However, these measurements could be affected by the surrounding environment of the lens galaxy. Thus, it is important to evaluate the cluster-scale mass for detailed mass modelling. We observed the Eye of Horus, a DSP sy…
Virial models and anisotropy of velocity dispersion in E-galaxies
Kondratyev, B. P.; Kireeva, E. N.
A tensor virial approach is used to construct detailed models of 22 flattened ellipticals. The models are combined with the new observational data: extended surface brightness distributions, the profiles of isophotes flattening and their twisting, the rotation curves and the velocity dispersion profiles. A key feature of these models is a rigorous…