相关论文: Physical Characteristics of Umbral Dots Derived fr…

Penumbrae are known to be area of mainly horizontal magnetic field surrounding umbrae of relatively large and mature sunspots. In this paper, we observationally studied the formation of penumbrae in NOAA10978, where several penumbral…

Two-dimensional surface photometry derived from Hubble Space Telescope imaging is presented for a sample of 225 early-type galaxies (assumed to be cluster members) in the fields of 9 clusters at redshifts $0.17 < z < 1.21$. The 94 luminous…

The eccentricity of a sub-stellar companion is an important tracer of its formation history. Directly imaged companions often present poorly constrained eccentricities. A recently developed prior framework for orbit fitting called…

We used the optical and near-infrared imagers located on the Liverpool, the IAC80, and the William Herschel telescopes to monitor 18 M7$-$L9.5 dwarfs with the objective of measuring their rotation periods. We achieved accuracies typically…

We present new Hubble Space Telescope (HST) ultraviolet and ground-based optical observations of the hot, metal-rich white dwarf GD 394. Extreme-ultraviolet (EUV) observations in 1992-1996 revealed a 1.15d periodicity with a 25 percent…

We analyse the population of near-Earth Long-Period Comets (LPCs) (perihelion distances q < 1.3 AU and orbital periods P > 10^3 yr). We have considered the sample of LPCs discovered during the period 1900-2009 and their estimated absolute…

WD 1145+017 was observed from 2015 November to 2016 July for the purpose of characterizing transit behavior of the white dwarf by dust clouds thought to be produced by fragments of an asteroid in close orbit with the star. Fortuitously,…

We present an analysis of the kinematics of Galactic disc white dwarf stars in the Solar neighbourhood using data from Gaia Data Release 2. Selection of white dwarfs based on parallax provides the first large, kinematically unbiased sample…

This paper reports the discovery and orbital characterization of two extreme trans-Neptunian objects (ETNOs), 2016 QV$_{89}$ and 2016 QU$_{89}$, which have orbits that appear similar to that of a previously known object, 2013 UH$_{15}$. All…

We present a method to analyze images of the coma of 67P/Churyumov-Gerasimenko obtained using OSIRIS, the main imaging system onboard \textit{Rosetta}, where dust aggregates can be seen as bright tracks because of their relative velocity…

Six images of IRC+10216 taken by the Hubble Space Telescope at three epochs in 2001, 2011, and 2016 are compared in the rest frame of the central carbon star. An accurate astrometry has been achieved with the help of Gaia Data Release 2.…

The mid-infrared (10-20 um) luminosity of elliptical galaxies is dominated by the integrated emission from circumstellar dust in red giant stars. As a single stellar population evolves, the rate of dusty mass loss from red giant stars…

Sunspot observations in chromospheric spectral lines have revealed the existence of short-lived linear bright transients, commonly referred to as penumbral micro-jets (PMJs). Details on the origin and physical nature of PMJs are to large…

We have investigated the accuracy and reliability of six methods used to determine the length of stellar bars in galaxies or N-body simulations. All these methods use ellipse fitting and Fourier decomposition of the surface brightness. We…

It is well-known that the global acoustic oscillations of the Sun's atmosphere can excite resonance modes within large-scale magnetic concentrations. These structures are conduits of energy between the different layers of the solar…

We study the emission of dust grains within the Orion Bar - a well-known, highly far-UV (FUV)-irradiated PDR. The Orion Bar because of its edge-on geometry provides an exceptional benchmark for characterizing dust evolution and the…

We present an analysis of the apsidal motion and light curve parameters of 54 never-before-studied galactic Algol-type binaries. This is the first analysis of such a large sample of eccentric eclipsing binaries in our Galaxy, and has…

We study the behavior of orbits in two different galactic dynamical models, describing the motion in the central parts of a triaxial elliptical galaxy with a dense nucleus. Numerical experiments show that both models display regular motion…

The lure of a 50 percent reduction in light has brought a multitude of observers and researchers to epsilon Aur every twenty-seven years, but few have paid attention to the system outside of eclipse. As early as the late 1800s, it was clear…

We present an overview and the first results from a large-scale pulsar timing programme that is part of the UTMOST project at the refurbished Molonglo Observatory Synthesis Radio Telescope (MOST) near Canberra, Australia. We currently…