Search Publications
New astrometric positions for six Jovian irregular satellites using Gaia DR3 in 2016 — 2021
Vienne, A.; Lin, F. R.; Peng, Q. Y. +2 more
The Jovian system is like a miniature solar system, with the system being more than twice as massive as all the other planets combined and having many natural satellites. Its formation and early evolution had a profound influence on our knowledge of the sculpting of the architecture of the solar system. Astrometric observations are of importance, …
NAROO program: Analysis of USNO Galilean observations 1967–1998
Lainey, V.; Robert, V.; Arlot, J. -E. +1 more
The New Astrometric Reduction of Old Observations (NAROO) program is dedicated to the measurement of astrophotographic plates and the analysis of old observations for scientific purposes. One of the main objectives of the NAROO program is to provide accurate positional measurements of planets and satellites to improve our knowledge of their orbits…
Astrometric observations of Phoebe from 2010 to 2019 based on Gaia DR3
Cheng, X.; Zhang, H. Y.; Yan, D. +2 more
A total of 914 positions of Phoebe were collected from 2010 to 2019 with three different telescopes, which were the 1.56 m telescope at the Sheshan station of Shanghai Astronomical Observatory, the 1.0 m telescope at the Kunming station of Yunnan Astronomical Observatory and the 2.4 m telescope at the Lijiang station of Yunnan Astronomical Observa…
NEOMOD 2: An updated model of Near-Earth Objects from a decade of Catalina Sky Survey observations
Granvik, Mikael; Chodas, Paul W.; Nesvorný, David +9 more
Catalina Sky Survey (CSS) is a major survey of Near-Earth Objects (NEOs). In a recent work, we used CSS observations from 2005-2012 to develop a new population model of NEOs (NEOMOD). CSS's G96 telescope was upgraded in 2016 and detected over 10,000 unique NEOs since then. Here we characterize the NEO detection efficiency of G96 and use G96's NEO …
The Uranus system from occultation observations (1977-2006): Rings, pole direction, gravity field, and masses of Cressida, Cordelia, and Ophelia
Nicholson, Philip D.; French, Richard G.; Hedman, Matthew M. +2 more
From an analysis of 31 Earth-based stellar occultations and three Voyager 2 occultations spanning 1977-2006 (French et al. 2023a), we determine the keplerian orbital elements of the centerlines of the nine main Uranian rings to high accuracy, with typical RMS residuals of 0.2-0.4 km and 1- σ formal errors in a , ae , and a sin i of order 0.1 km, r…
Uranus ring occultation observations: 1977-2006
Nicholson, Philip D.; French, Richard G.; Sicardy, Bruno +25 more
The Uranian rings were discovered serendipitously on 10 March 1977 during a stellar occultation (Elliot et al., 1977a; Millis et al., 1977), and a rich set of subsequent Earth-based occultations revealed that these narrow and sharp-edged rings were eccentric and inclined, precessing under the gravitational influence of the oblate central planet. C…
Spins and shapes of basaltic asteroids and the missing mantle problem
Hasegawa, Sunao; Oszkiewicz, Dagmara; Skiff, Brian A. +31 more
Basaltic V-type asteroids are common in the inner part of the Main Asteroid Belt and much less abundant in the mid and outer parts. They are of scientific interest because they sample crusts and mantles of theoretically plentiful differentiated planetesimals that existed in the Solar System four billion years ago. Some Solar System theories sugges…
Astrometric observations of the main Saturnian satellites from 2004 to 2014 based on Gaia DR3
Zhang, H. Y.; Yan, D.; Qiao, R. C. +1 more
A total of 3169 astrometric positions of the seven main satellites of Saturn: Enceladus, Tethys, Dione, Rhea, Titan, Hyperion and Iapetus were obtained in the time span 2004-2014 from observations made with 1.56 m telescope at Sheshan station of Shanghai Observatory, CAS. We compared our observations to the theoretical positions retrieved from IMC…
Investigating the most promising Yarkovsky candidates using Gaia DR2 astrometry
Oszkiewicz, Dagmara; Bartczak, Przemysław; Dziadura, Karolina
The Yarkovsky drift is a major factor driving the orbital evolution of asteroids. To date, the effect has been detected for a few hundred asteroids, mainly near-Earth objects. Before the start of the European Space Agency Gaia mission, the expectation was to recognize many other asteroids manifesting the Yarkovsky drift through the high precision …
Astrometric observations and analysis of Triton during 2013-2019
Zhang, H. Y.; Yan, D.; Qiao, R. C. +2 more
Triton is the largest irregular satellite of Neptune. A total of 1135 new observed positions of Triton in the period 2013-2019 were collected by the 1.0 m telescopes at Yunnan Astronomical Observatory of CAS during 13 nights. These positions of Triton were obtained based on Gaia DR2 catalogue. We compared our observations to the theoretical positi…