Results 21 to 30 of about 6,728 (225)
Photographic zenith tubes observations to improve HIPPARCOS proper motion in declination of some stars [PDF]
A procedure of calculation and results of an attempt to improve proper motions in declination for some HIPPARCOS stars are presented. A long series of optical observations of these stars observed with Photographic Zenith Tubes (PZT) are used.
Damljanović Goran M.
doaj +1 more source
Digitization of the Belgrade Astronomical Observatory's vertical circle observational heritage [PDF]
The aim of the paper is to present the digitization of the results of last observations of bright stars made by the Belgrade vertical circle ASKANIA N±80118 (D = 190 mm, f = 2578 mm) at the Astronomical Observatory of Belgrade.
Šegan S., Šegan-Radonjić M.
doaj +1 more source
Macho Photometry and Astrometry [PDF]
MACHOs (Massive Astrophysical Compact Halo Objects) have been discovered by their relativistic amplification of light from distant stars as they crossed very near to the line-of-sight. The very few events were detected from more than a billion photometric measurements of millions of stars in the LMC.
Høg, E. +2 more
openaire +2 more sources
General relativistic effects in astrophyiscal systems have been detected thanks to accurate astrometric measurements. We outline some keystones of astrometry such as stellar aberration (argument development during the years 1727-1872); Mercury's perihelion precession (1845-1916); solar disk oblateness (1966-2001); relativistic light deflection (1916 ...
openaire +2 more sources
Gaia: The Astrometry Revolution [PDF]
The power of micro-arcsecond (μas) astrometry is about to be unleashed. ESA's Gaia mission, now headed towards the end of the first year of routine science operations, will soon fulfil its promise for revolutionary science in countless aspects of ...
SOZZETTI, Alessandro +4 more
core +1 more source
VERA’s 20 yr Evolution in Science and Technology
We review the past 20 yr evolution of VERA (VLBI Exploration of Radio Astrometry) in both science and techinology. VERA is a VLBI array in Japan which consists of four 20 m-diameter telescopes, originally dedicated to phase-referencing VLBI astrometry ...
Mareki Honma +3 more
doaj +1 more source
Exploring the Interior Structure of (16) Psyche Through Basin‐Scale Collisions
Abstract Asteroid (16) Psyche, the largest member of the M/X‐type asteroids, may be the leftover core of a differentiated planetesimal. As such (16) Psyche will be explored in detail by NASA's discovery‐class Psyche mission in 2029. This will be the first mission to orbit a metal‐rich asteroid, or any asteroid in the 100–500 km size range.
Namya Baijal +7 more
wiley +1 more source
Al‐Khadhaf: The first camera‐observed (H5–6) meteorite fall from Oman
Abstract A fireball camera system installed in 2022 by the Oman Meteorite Monitoring Project (OMMP) as part of the Global Fireball Observatory (GFO) recorded a 3.2 s fireball on March 8, 2022 at 8:15 p.m. UTC. A meteoroid of 4 ± 2 kg entered the atmosphere at 14.0 km/s.
Anna Zappatini +18 more
wiley +1 more source
Since the advent of Gaia catalog, positional precision of a ground-based telescope can be greatly improved by correction of more subtle errors, including positional biases induced by atmospheric turbulence, and some instrumental factors such as geometric
Z. J. Zheng +3 more
doaj +1 more source
On 20 December 2020, after more than 2 years of quiescence at Kīlauea Volcano, Hawaiʻi, renewed volcanic activity in the summit crater caused boiling of the water lake over a period of ∼90 min. The resulting water‐rich, electrified plume rose to 11–13 km
Ryan C. Cahalan +11 more
doaj +1 more source

