Results 51 to 60 of about 4,968 (216)
Introduction: In recent decades, numerous large survey projects have been initiated to enhance our understanding of the cosmos. Among these, the Vera C.
Yuanyu Hong +7 more
doaj +1 more source
High precision measurements of the celestial coordinates of pulsars are desirable for a number of reasons. If carried out at several epochs, the measurements can yield angular proper motions; together with distance estimates based on dispersion measure, the proper motion of a pulsar reveals two of three components of its space velocity, and ...
Joseph H. Taylor +3 more
openaire +1 more source
Uncertainties in Ground‐Based Visual Double Star Measures—II Accuracy of Measures
ABSTRACT Letchford and White 2025, Paper I, determined the uncertainties in ground‐based historic measures of double stars. In this paper, the accuracy of 26,205 ground‐based measures of 857 visual double stars, made since ∼$$ \sim $$1780, is determined relative to space‐based measures based on positions and proper motion from the HIPPARCOS (via ASCC ...
Graeme L. White, Roderick R. Letchford
wiley +1 more source
Deep Space Network Radio Science and Ground‐Based Planetary Radar in the Next Decade
Abstract The Deep Space Network (DSN) has been a core operational element of NASA's crewed and robotic exploration of the Solar System since the early 1960s. The primary role of the DSN has been to acquire telemetry and navigation data, but over the years, its radiometric and radar capabilities have expanded to form a system for obtaining unique ...
R. S. Park +13 more
wiley +1 more source
RESULTS OF PROCESSING OF ASTRONEGATIVES WITH COMMERCIAL SCANNER
Astrometric errors depending on the method of scanning with different spatial resolutions were studied with commercial scanner such as Epson Perfection V750 Pro.
Yu. I. Protsyuk +3 more
doaj +1 more source
Bound Orbits and Epicyclic Motions around Renormalization Group Improved Schwarzschild Black Holes
We study timelike particles’ bound orbits around renormalization group improved Schwarzschild black holes (RGISBHs), which originate from renormalization group improvement of the Einstein–Hilbert action by using the running Newton constant.
Hou-Yu Lin, Xue-Mei Deng
doaj +1 more source
The Slow‐Rotating Nucleus of Comet C/2013 R1 (Lovejoy)
ABSTRACT The close approach of comet C/2013 R1 (Lovejoy) allowed us to conduct an in‐depth study of the morphology of the inner coma. From the measurement of the dust emission structures expanding near the cometary nucleus in November–December 2013, we derived a slow rotation period of 47.8±1.2$$ 47.8\pm 1.2 $$ h.
Federico Manzini +12 more
wiley +1 more source
The paper discusses and illustrates the steps of basic processing of digitized image of astro negatives. Software for obtaining of a rectangular coordinates and photometric values of objects on photographic plates was created in the environment ...
Yu. I. Protsyuk +2 more
doaj +1 more source
A Slowly Pulsating Run‐Away B Star at High Galactic Latitude Ejected From a Spiral Arm
ABSTRACT We report the discovery of the young B6 V run‐away star LAMOST J083323.18 + 430825.4, 2.5 kpc above the Galactic plane. Its atmospheric parameters and chemical composition are determined from LAMOST spectra, indicating normal composition. Effective temperature (Teff$$ {T}_{\mathrm{eff}} $$ = 14,500$$ \mathrm{14,500} $$ K) and gravity (logg ...
Ulrich Heber +3 more
wiley +1 more source
This catalogue contains the results of 1321 right ascensions observations of 2dj Radio References Stars obtained al Odessa with the Repsold transit circle in 1990-1993.
A. P. Chelombit'ko
doaj +1 more source

