Related papers: Accuracy of meteor positioning from space-and grou…
Meteoroids originating from the local interstellar medium, traverse the solar system. This has been proven by in situ measurements by interplanetary spacecraft as well as highly sensitive radar measurements. Early attempts to detect…
Astrometry is a powerful technique in astrophysics to measure three-dimensional positions of stars and other astrophysical objects, including exoplanets and the gravitational influence they have on each other. Interferometric astrometry is…
We describe an improved technique for using the backscattered phase from meteor radar echo measurements just prior to the specular point ($t_{0}$) to calculate meteor speeds and their uncertainty. Our method, which builds on earlier work of…
We give a detailed description of the installation and operation of a double-station meteor detection system which formed part of a research & education project between Korea Astronomy Space Science Institute and Daejeon Science Highschool.…
We present an approach for utilizing astrometric orbit information to improve the yield of planetary images and spectra from a follow-on direct detection mission. This approach is based on the notion-strictly hypothetical-that if a…
Background. Astrometry at or below the micro-arcsec level with an imaging telescope assumes that the uncertainty on the location of an unresolved source can be an arbitrarily small fraction of the detector pixel, given a sufficient photon…
Photometric light curves suffer from fundamental degeneracies that limit surface information recovery. We demonstrate that astrometry enables access to complementary information through photocentre variations induced by rotating surface…
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…
The forecasting of meteor showers is currently very good at predicting the timing of meteor outbursts, but still needs further work regarding the level of a given shower. Moreover, uncertainties are rarely provided, leaving the end user…
The modulation of high-energy transients' (or steadily emitting sources') light curves due to the imperfect alignment of the detector's view axis with the spin axis in a spin-stabilized satellite is derived. It is shown how the orientation…
Using actual flight data from a 50-cm-class microsatellite whose mission and operations have already been completed, this study re-evaluates satellite attitude determination performance and the error characteristics of onboard attitude…
Background. Relative astrometry at or below the micro-arcsec level with a 1m class space telescope has been repeatedly proposed as a tool for exo-planet detection and characterization, as well as for several topics at the forefront of…
Astrometry - the precise measurement of celestial positions and motions - is entering the micro-arcsecond ($\mu$as) era at multiple wavelengths, enabling new insights on compact objects across all mass scales. Here we review how…
We present a study of the source positioning accuracy of the LECS and MECS instruments on-board BeppoSAX. From the analysis of a sample of archival images we find that a systematic error, which depends on the spacecraft roll angle and has…
Mega-constellations in Low Earth Orbit have the potential to revolutionise worldwide internet access. The concomitant potential of these mega-constellations to impact space sustainability, however, has prompted concern from space actors as…
We present improvements to the pointing accuracy of the South Pole Telescope (SPT) using machine learning. The ability of the SPT to point accurately at the sky is limited by its structural imperfections, which are impacted by the extreme…
For microlensing case angular distances between images or typical astrometric shifts due to microlensing are about $10^{-5}-10^{-6} \mu as$. Such an angular resolution will be reached with the space space--ground interferometer Radioastron.…
A method is developed for fitting theoretically predicted astronomical spectra to an observed spectrum. Using a hierarchical Bayesian principle, the method takes both systematic and statistical measurement errors into account, which has not…
Astrometry at centimeter wavelengths using Very Long Baseline Interferometry is approaching accuracies of ~1 uas for the angle between a target and a calibrator source separated by <1 degree on the sky. The BeSSeL Survey and the Japanese…
Understanding the role of ozone in the Mesosphere/Lower Thermosphere (MLT) region is essential for understanding the atmospheric processes in the upper atmosphere. Earlier studies have shown that it is possible to use overdense meteor…