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221. The SkyMapper DR3 SSOs
ID:
ivo://CDS.VizieR/J/A+A/658/A109
Title:
The SkyMapper DR3 SSOs
Short Name:
J/A+A/658/A109
Date:
22 Feb 2022
Publisher:
CDS
Description:
The populations of small bodies of the Solar System (asteroids, comets, and Kuiper Belt objects) are used to constrain the origin and evolution of the Solar System. Their orbital distribution and composition distribution are both required to track the dynamical pathway from their formation regions to their current locations. We aim to increase the sample of Solar System objects (SSOs) that have multifilter photometry and compositional taxonomy. Methods. We searched for moving objects in the SkyMapper Southern Survey. We used the predicted SSO positions to extract photometry and astrometry from the SkyMapper frames. We then applied a suite of filters to clean the catalog from false-positive detections. We finally used the near-simultaneous photometry to assign a taxonomic class to objects. We release a catalog of 880,528 individual observations, consisting of 205515 known and unique SSOs. The catalog completeness is estimated to be about 97% down to V=18mag and the purity is higher than 95% for known SSOs. The near-simultaneous photometry provides either three, two, or a single color that we use to classify 117356 SSOs with a scheme consistent with the widely used Bus-DeMeo taxonomy. The present catalog contributes significantly to the sample of asteroids with known surface properties (about 40% of main-belt asteroids down to an absolute magnitude of 16). We will release more observations of SSOs with future SkyMapper data releases.
222. Time-series photometry of 2012 DA14
ID:
ivo://CDS.VizieR/J/A+A/559/A106
Title:
Time-series photometry of 2012 DA14
Short Name:
J/A+A/559/A106
Date:
21 Oct 2021
Publisher:
CDS
Description:
The object 2012 DA14 is a near-Earth asteroid with a size of several tens of meters. It had approached closely the Earth on 15 February 2013 UT, providing an opportunity for precise measurements of this tiny asteroid. The solar phase angle of 2012 DA14 had varied widely around its closest approach but was almost constant during the following night. We performed time-series photometric observations on those two nights to determine the rotational properties and phase effect. The observations were carried out using the 0.55-m telescope at Saitama University, Japan. The R-band images were obtained continuously over a 2h period at the closest approach and for about 5h on the next night.
223. TNOs and Centaurs observed within the DES
ID:
ivo://CDS.VizieR/J/AJ/157/120
Title:
TNOs and Centaurs observed within the DES
Short Name:
J/AJ/157/120
Date:
21 Oct 2021
Publisher:
CDS
Description:
Trans-Neptunian objects (TNOs) are a source of invaluable information to access the history and evolution of the outer solar system. However, observing these faint objects is a difficult task. As a consequence, important properties such as size and albedo are known for only a small fraction of them. Now, with the results from deep sky surveys and the Gaia space mission, a new exciting era is within reach as accurate predictions of stellar occultations by numerous distant small solar system bodies become available. From them, diameters with kilometer accuracies can be determined. Albedos, in turn, can be obtained from diameters and absolute magnitudes. We use observations from the Dark Energy Survey (DES) from 2012 November until 2016 February, amounting to 4292847 charge-coupled device (CCD) frames. We searched them for all known small solar system bodies and recovered a total of 202 TNOs and Centaurs, 63 of which have been discovered by the DES collaboration as of the date of submission. Their positions were determined using the Gaia Data Release 2 (Cat. I/345) as reference and their orbits were refined. Stellar occultations were then predicted using these refined orbits plus stellar positions from Gaia. These predictions are maintained, and updated, in a dedicated web service. The techniques developed here are also part of an ambitious preparation to use the data from the Large Synoptic Survey Telescope (LSST), that expects to obtain accurate positions and multifilter photometry for tens of thousands of TNOs.
224. Trojan asteroids in the Kepler campaign 6 field
ID:
ivo://CDS.VizieR/J/AJ/153/116
Title:
Trojan asteroids in the Kepler campaign 6 field
Short Name:
J/AJ/153/116
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on a Kepler spacecraft survey during the K2 mission to characterize the rotational properties of 56 Trojan asteroids in the L4 cloud. More than one rotational period was observed for 51 of these targets, allowing for well constrained lightcurve rotation periods and amplitudes, five of which are found to be in conflict with previously published values. We find ~10% of objects have rotational periods longer than 100hr, an excess of slow rotators 10 times larger than suggested from the literature. Investigation of the rotational frequencies of our Kepler sample when combined with high-quality lightcurves in the literature reveals the distribution of rotational frequencies is non-Maxwellian even when consideration is given to size-dependent variations in rotational rate. From investigation of lightcurve shapes and amplitudes, we estimate the binary fraction within the Trojan population to be ~6%-36% depending on the methodology utilized to identify binary candidates.
225. (174567) Varda multi-chord stellar occultation
ID:
ivo://CDS.VizieR/J/A+A/643/A125
Title:
(174567) Varda multi-chord stellar occultation
Short Name:
J/A+A/643/A125
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present here results of the first-ever recorded stellar occultation by the large trans-Neptunian object (174567) Varda that was observed on September 10th, 2018. Varda belongs to the high-inclination dynamically excited population, and has a satellite, Ilmare, which is half the size of Varda.
226. V-band photometry of asteroids from ASAS-SN
ID:
ivo://CDS.VizieR/J/A+A/654/A48
Title:
V-band photometry of asteroids from ASAS-SN
Short Name:
J/A+A/654/A48
Date:
22 Feb 2022
Publisher:
CDS
Description:
We present V-band photometry of the 20000 brightest asteroids using data from the All-Sky Automated Survey for Supernovae (ASAS-SN) between 2012 and 2018. We were able to apply the convex inversion method to more than 5000 asteroids with more than 60 good measurements in order to derive their sidereal rotation periods, spin axis orientations, and shape models. We derive unique spin state and shape solutions for 760 asteroids, including 163 new determinations. This corresponds to a success rate of about 15%, which is significantly higher than the success rate previously achieved using photometry from surveys. We derive the first sidereal rotation periods for additional 69 asteroids. We find good agreement in spin periods and pole orientations for objects with prior solutions. We obtain a statistical sample of asteroid physical properties that is sufficient for the detection of several previously known trends, such as the underrepresentation of slow rotators in current databases, and the anisotropic distribution of spin orientations driven by the nongravitational forces. We also investigate the dependence of spin orientations on the rotation period. Since 2018, ASAS-SNhas been observing the sky with higher cadence and a deeper limiting magnitude, which will lead to many more new solutions in just a few years.
227. Veritas family members Yarkovsky drift rates
ID:
ivo://CDS.VizieR/J/MNRAS/469/4400
Title:
Veritas family members Yarkovsky drift rates
Short Name:
J/MNRAS/469/4400
Date:
21 Oct 2021
Publisher:
CDS
Description:
The age of a young asteroid family can be determined by tracking the orbits of family members backward in time and showing that they converge at some time in the past. Here we consider the Veritas family. We find that the membership of the Veritas family increased enormously since the last detailed analysis of the family. Using backward integration, we confirm the convergence of nodal longitudes {Omega}, and, for the first time, also obtain a simultaneous convergence of pericenter longitudes {varpi}. The Veritas family is found to be 8.23^+0.37^_-0.31_Myr old. To obtain a tight convergence of {Omega} and {varpi}, as expected from low ejection speeds of fragments, the Yarkovsky effect needs to be included in the modeling of the past orbital histories of Veritas family members. Using this method, we compute the Yarkovsky semi-major axis drift rates, d_a_/dt, for 274 member asteroids. The distribution of d_a_/dt values is consistent with a population of C-type objects with low densities and low thermal conductivities. The accuracy of individual d_a_/dt measurements is limited by the effect of close encounters of member asteroids to (1) Ceres and other massive asteroids, which cannot be evaluated with confidence.
228. (4) Vesta adopted polarimetric light curves
ID:
ivo://CDS.VizieR/J/MNRAS/456/248
Title:
(4) Vesta adopted polarimetric light curves
Short Name:
J/MNRAS/456/248
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of the in situ exploration of the asteroid (4) Vesta by the Dawn spacecraft open new perspectives in the field of interpretation of remote-sensing polarimetric measurements of asteroids. (4) Vesta has long been known to be the only asteroid exhibiting a cyclic variation of the degree of linear polarization of the sunlight scattered by its surface, with a period which is synchronous with the object's rotation. This variation must be the consequence of some heterogeneity of the asteroid's surface, including regions characterized by different albedo, or composition, or regolith properties, or a combination of the above features. For a long time, this kind of conclusion has remained essentially qualitative. Now, after the extensive exploration of Vesta's surface by Dawn, it is possible to interpret the data set of polarimetric measurements of Vesta, including some unpublished data presented here for the first time, in terms of a correspondence between the degree of linear polarization and the variation of local properties of the surface visible to ground-based observers during Vesta's rotation, as seen at different epochs and under different illumination conditions. This makes it possible to refine our knowledge of the empirical relation between polarization properties and albedo, which is commonly used to derive the albedo from remote-sensing measurements of linear polarization of atmosphereless Solar system bodies.
229. Visible colors of Centaurs and KBOs
ID:
ivo://CDS.VizieR/J/A+A/577/A35
Title:
Visible colors of Centaurs and KBOs
Short Name:
J/A+A/577/A35
Date:
21 Oct 2021
Publisher:
CDS
Description:
Since the discovery of the Kuiper Belt, broadband surface colors were thoroughly studied as a first approximation to the objects reflectivity spectra. Visible colors (BVRI) have proven to be a reasonable proxy for real spectra, which are rather linear in this range. On the contrary, near-IR colors (JHK bands) could be misleading when absorption features of ices are present in the spectra. Although the physical and chemical information provided by colors are rather limited, broadband photometry remains the best tool for establishing the bulk surface properties of KBOs and Centaurs. In this work, we explore for the first time general, recurrent effects in the study of visible colors that could affect the interpretation of the scientific results: i) how a correlation could be missed or weaken due to the data error bars, ii) the "risk" of missing-out an existing trend due to low sampling, and the possibility to make quantified predictions on the sample size needed to detect a trend at a given significance level, assuming the sample is unbiased, iii) the use of partial correlations to disentangle the mutual effect of two or more (physical) parameters, iv) the sensitivity of the "reddening line" tool to the central wavelength of the filters used. To illustrate and apply these new tools, we have compiled the visible colors and orbital parameters of about 370 objects available in the literature, assumed, by default, as unbiased samples, and carried-out the "traditional" analysis per dynamical family. Our results show in particular how: a) data error-bars impose a limit on the detectable correlations regardless of sample size and, therefore, once that limit is achieved it is important to diminish the error-bars but pointless to enlarge the sampling with the same or larger errors; b) almost all dynamical families still require larger samplings to "ensure" the detection of correlations stronger than +/-0.5, i.e. correlations that may "explain" ~25% or more of the color variability; c) the correlation strength between (V-R) vs. (R-I) is systematically lower than the one between (B-V) vs. (V-R) and not related with error-bar differences between these colors; d) it is statistically equivalent to use any of the different "flavors" of orbital excitation or collisional velocity parameters regarding the famous color-inclination correlation among Classical KBOs --- which no longer evidences to be a strong correlation --- whereas the inclination and Tisserand parameter relative to Neptune cannot be separated from one another; and e) Classical KBOs are the only dynamical family which evidences for neither (B-V) vs. (V-R) nor (V-R) vs. (R-I) correlations, being, therefore, the family with the most unpredictable visible surface reflectivities.
230. VISTA-VHS (MOVIS) minor planets NIR photometry
ID:
ivo://CDS.VizieR/J/A+A/591/A115
Title:
VISTA-VHS (MOVIS) minor planets NIR photometry
Short Name:
J/A+A/591/A115
Date:
21 Oct 2021
Publisher:
CDS
Description:
The NIR photometric data of minor planets observed by the VISTA-VHS survey. This survey uses Y, J, H, and Ks filters for imaging the entire sky of the southern hemisphere. A total of 39947 Solar System objects were detected in the VISTA VHS Data Release 3. The detections found include: 52 NEAs, 325 Mars Crossers, 515 Hungaria asteroids, 38428 Main Belt asteroids, 146 Cybele asteroid, 147 Hilda asteroids, 270 Trojans, 13 comets, 12 Kuiper Belt objects, and Neptune with its 4 satellites. About 34998 of these objects were imaged with at least two different filters.