Related papers: Nearby Motionless Stars
A direct observation of the spiral structure of the Galaxy is hindered by our position in the middle of the Galactic plane. We propose a method based on the analysis of the birthplaces of high Galactic latitude runaway stars to map the…
This chapter reviews various methods of detecting planetary companions to stars from an observational perspective, focusing on radial velocities, astrometry, direct imaging, transits, and gravitational microlensing. For each method, this…
We present a new technique for estimating the distance to young open clusters. The method requires accurate measurement of the axial rotation period of late-type members of the cluster: rotation periods are first combined with projected…
As astronomical photometric surveys continue to tile the sky repeatedly, the potential to pushdetection thresholds to fainter limits increases; however, traditional digital-tracking methods cannotachieve this efficiently beyond time scales…
We present the discovery of a previously unknown very nearby star - LHS 2090 at a distance of only d=6 pc. In order to find nearby (i.e. d < 25 pc) red dwarfs, we re-identified high proper motion stars ($\mu >$ 0.18 arcsec/yr) from the NLTT…
We explored the regions within a radius of 25 arcsec around 473 nearby, low-metallicity G- to M-type stars using (VR)I optical filters and small-aperture telescopes. About 10% of the sample was searched up to angular separations of 90…
In this article we outline the structure of a general relativistic astrometric model which has been developed to deduce the position and proper motion of stars from 1-microarcsecond optical observations made by an astrometric satellite…
Following previous suggestions of other researchers, this paper discusses the prospects for astrometric observation of MACHO gravitational microlensing events. We derive the expected astrometric observables for a simple microlensing event…
Runaway stars are characterized by higher space velocities than typical field stars. They are presumed to have been ejected from their birth places by one or more energetic mechanisms, including supernova explosions. Accurate radial…
In this article, we describe a very simple technique to locate naked-eye planets in the sky, to an accuracy of $\sim 1^{\circ}$. The procedure, comprising just three steps, involves very simple manual calculations for planetary orbits…
Getting spectra at good signal-to-noise ratios takes orders of magnitudes more time than photometric observations. Building on the technique developed for photometric redshift estimation of galaxies, we develop and demonstrate a…
This tutorial covers the use of absolute astrometry, in particular from the combination of the Hipparcos and Gaia missions, to identify faint companions to nearby stars and to measure the masses and orbits of those companions. Absolute…
Transits of bright stars offer a unique opportunity to study detailed properties of extrasolar planets that cannot be determined through radial-velocity observations. We propose a new technique to find such systems using all-sky…
The principal goal of this paper is to specify conditions of detection of unresolved binaries by multicolor photometry. We have developed a method for estimating the critical distance at which an unresolved binary of given mass and age can…
Asteroseismology of massive stars has recently begun a revolution thanks to high-precision time series photometry from space telescopes. This has allowed accurate and robust constraints on interior physical processes, such as mixing and…
With several detections, the technique of gravitational microlensing has proven useful for studying planets that orbit stars at Galactic distances, and it can even be applied to detect planets in neighbouring galaxies. So far, planet…
Multi-messenger astronomy is of great interest. The localization speed of gravitational wave sources is important for the success of electromagnetic follow-up. Although current gravitational wave source localization methods take up to a few…
The Pristine survey is a narrow-band, photometric survey focused around the wavelength region of the Ca II H & K absorption lines, designed to efficiently search for extremely metal-poor stars. In this work, we use the first results of a…
Direct imaging searches for exoplanets around stars detect many spurious candidates that are in fact background field stars. To help distinguish these from genuine companions, multi-epoch astrometry can be used to identify a common proper…
I present a review of astrometric techniques and instrumentation utilized to search for, detect, and characterize extra-solar planets. First, I briefly summarize the properties of the present-day sample of extrasolar planets, in connection…