Search Publications
Detecting Exoplanets Using Eclipsing Binaries as Natural Starshades
Zabludoff, Ann I.; Guyon, Olivier; Bellotti, Stefano +2 more
We investigate directly imaging exoplanets around eclipsing binaries using the eclipse as a natural tool for dimming the binary and thus increasing the planet to star brightness contrast. At eclipse, the binary becomes pointlike, making coronagraphy possible. We select binaries where the planet-star contrast would be boosted by >10× during ecli…
ACRONYM IV: Three New, Young, Low-mass Spectroscopic Binaries
Kraus, Adam L.; Shkolnik, Evgenya L.; Bowler, Brendan P. +4 more
As part of our search for new low-mass members of nearby young moving groups (YMGs), we discovered three low-mass, spectroscopic binaries, two of which are not kinematically associated with any known YMG. Using high-resolution optical spectroscopy, we measure the component and systemic radial velocities of the systems, as well as their lithium abs…
Re-Reduction of the Old Photographic Observations of Interamnia (704) Based on Gaia DR2 Reference Catalogue
Protsyuk, Yu. I.; Maigurova, N. V.
A new astrometric reduction of old photographic astroplates benefiting from integration of modern technologies such as the high precision digitizing machines and the high precision Gaia DR2 catalogue could be useful to study the orbital motion of Solar system minor bodies. Based on the newly released Gaia DR2 star catalogue, the scans of the photo…
Multiple populations of Hβ emission line stars in the Large Magellanic Cloud cluster NGC 1971
Piatti, Andrés E.
We revisited the young Large Magellanic Cloud star cluster NGC 1971 with the aim of providing additional clues to our understanding of its observed extended main-sequence turnoff (eMSTO), a feature commonly seen in young star clusters that has recently been argued to be caused by a real age spread similar to the cluster age (∼160 Myr). We combined…
Vertical controlled landing on 67P / Churyumov-Gerasimenko
Probst, A.; San Martín, A.; Zimmer, A. +2 more
With the increasing interest of small body science due to its important role in the puzzle of the solar system formation, missions to small bodies are studied and developed in preparation for future exploration. Together with the operational experience gained and the general rapid technology development, landers and surface mobility elements enabl…
Global Parameters of the Newly-discovered W UMa Stars WISEJ004327.7+722407 and WISEJ234557.8+510456
Ibryamov, S.; Kjurkchieva, D.
Photometric observations in g' and i' bands of the newly-discovered W UMa stars WISEJ004327.7+722407 and WISEJ234557.8+510456 are presented. The two targets are with shallow-contact configurations and their components are of G--K spectral type. We found that WISEJ004327.7+722407 is of A subtype while WISEJ234557.8+510456 is of W subtype. The diffe…
Quantitative assessment of water content and mineral abundances at Gale crater on Mars with orbital observations
Liu, Yang; Zou, Yongliao; Stachurski, Federico +1 more
Context. The information of water content can help to improve atmospheric and climate models, and thus provide a better understanding of the past and present role of water and aqueous alteration on Mars. Mineral abundances can provide unique constraints on their formation environments and thus also on the geological and climate evolution of Mars. …
Revised Orbital Parameters of Beaming Eclipsing Binary System HV Cnc from Kepler Photometry
Gürol, Birol; Gökay, Gökhan; Özdemir, Sacit
High precision photometry gathered from Kepler database and radial velocity measurements of the HV Cnc system found in the literature were simultaneously analyzed by the Wilson-Devinney (WD) code to better understand system parameters. Some physical quantities needed by the WD code in iterations, such as limb darkening coefficients, Kurucz's model…
Comparative Study of a Sunspot at Two Different Instances of Time
Hamedivafa, Hashem
We investigate the evolutionary effects on the brightness of a sunspot as well as on the properties of its fine-structures using two sets of time series of G-band images of a single sunspot in NOAA 10944 recorded at two symmetric locations on the solar disc by Hinode/SOT (Solar Optical Telescope). The second time series (phase W) was recorded 2.5 …
Spectrum of imbalanced Alfvénic turbulence at ion-kinetic scales in the solar wind
Voitenko, Y. M.; Gogoberidze, G.
Using a semi-phenomenological model of the imbalanced Alfvénic turbulence, we study the turbulence transition from magnetohydrodynamic to sub-ion kinetic scales in the conditions typical for the fast solar wind. We show that the transition takes place in a wide wave number interval where the energy spectrum does not follow any power law. For large…