- ID:
- ivo://CDS.VizieR/J/A+A/657/A80
- Title:
- Asteroides phase curves using SLOAN MOC
- Short Name:
- J/A+A/657/A80
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Large photometric surveys are producing, and will continue doing it, massive amounts of data on small bodies. Usually,these data will be sparsely obtained at arbitrary (and unknown) rotational phases. Therefore, new methods to process such data need to be developed to make the most of those large catalogs. We aim to produce a method to create phase curves of small bodies considering the uncertainties introduced not only by the nominal errors in the magnitudes, but also the effect introduced by rotational variations.We use as a benchmark the data from the SLOAN Moving Objects Catalog with the objective to construct phase curves of all small bodies in there, in the u, g, r, i, and z, filters. We will obtain from the phase curves the absolute magnitudes and set up with them the absolute colors, which are the colors of the asteroids not affected by changes in phase angle. We select objects with >3 observations taken in, at least, one filter and spanned over a minimum of 5 degrees in phase angle. We developed a method that combines Monte Carlo simulations and Bayesian inference to estimate the absolute magnitudes using the HG12 photometric system. We obtained almost 15000 phase curves, about 12000 including all five filters. The absolute magnitudes and absolute colors are compatible with previously published data, supporting our method.Conclusions. The method we developed is fully automatic and well suited to be run on large amounts of data. Moreover, it includes the nominal uncertainties in the magnitudes and the whole distribution of possible rotational states of the objects producing, possibly,less precise values, i.e., larger uncertainties, but more accurate, i.e., closer to the real value. To the best of our knowledge, this work is the first to include the effect of rotational variations in such a way.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/150/75
- Title:
- Asteroid light curves from PTF survey
- Short Name:
- J/AJ/150/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We fit 54296 sparsely sampled asteroid light curves in the Palomar Transient Factory survey to a combined rotation plus phase-function model. Each light curve consists of 20 or more observations acquired in a single opposition. Using 805 asteroids in our sample that have reference periods in the literature, we find that the reliability of our fitted periods is a complicated function of the period, amplitude, apparent magnitude, and other light-curve attributes. Using the 805-asteroid ground-truth sample, we train an automated classifier to estimate (along with manual inspection) the validity of the remaining ~53000 fitted periods. By this method we find that 9033 of our light curves (of ~8300 unique asteroids) have "reliable" periods. Subsequent consideration of asteroids with multiple light-curve fits indicates a 4% contamination in these "reliable" periods. For 3902 light curves with sufficient phase-angle coverage and either a reliable fit period or low amplitude, we examine the distribution of several phase-function parameters, none of which are bimodal though all correlate with the bond albedo and with visible-band colors. Comparing the theoretical maximal spin rate of a fluid body with our amplitude versus spin-rate distribution suggests that, if held together only by self-gravity, most asteroids are in general less dense than ~2g/cm^3^, while C types have a lower limit of between 1 and 2g/cm3. These results are in agreement with previous density estimates. For 5-20km diameters, S types rotate faster and have lower amplitudes than C types. If both populations share the same angular momentum, this may indicate the two types' differing ability to deform under rotational stress. Lastly, we compare our absolute magnitudes (and apparent-magnitude residuals) to those of the Minor Planet Center's nominal (G=0.15, rotation-neglecting) model; our phase-function plus Fourier-series fitting reduces asteroid photometric rms scatter by a factor of ~3.
- ID:
- ivo://CDS.VizieR/J/other/OAP/31.235
- Title:
- 2728 asteroid positions (Kitab obs.)
- Short Name:
- J/other/OAP/31.2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photographic observations of XX century contained numerous and varied information about all objects and events of the Universe fixed on the astronegatives. The original and interesting observations of small bodies of the Solar system in previous years can be selected and used for various scientific tasks. Existing databases and online services can help make such selection easily and quickly. The observations of chronologically earlier oppositions, photometric evaluation of brightness for long periods of time allow refining the orbits of asteroids and identifying various non-stationarities. Photographic observations of the Northern Sky Survey project (FON project) were used for global search for small bodies of Solar system. About 2000 photographic plates of Kitab part of the FON project were made using Double Wide Angle Astrograph at the Kitab observatory (Uzbekistan) during 1981-1989. Early, using that digitized observations the catalogue of equatorial coordinates and stellar magnitudes for more than 13 million stars and galaxies up to B=17.5m was compiled. At present, we analyzed all processing results for the search of asteroids and compiled the catalogue of equatorial coordinates and stellar magnitudes of them. As a result more than 4500 asteroids and comets with visual magnitude from 7.7m to 17.5m were identified now. All positions of asteroids were compared with ephemeris. A preliminary analysis of O-C differences was carried out. New and interesting are that the moments of official discovery of some identified asteroids much later than their moments of Kitab's observation. In addition, some of them are the earliest observations of these asteroids in the world among all known observations. More than 915 observations of such asteroids have been found on the plates of Kitab part of the FON project.
- ID:
- ivo://CDS.VizieR/J/AJ/158/227
- Title:
- Asteroseismic parameters of RGB stars
- Short Name:
- J/AJ/158/227
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Every Sun-like star will eventually evolve into a red giant, a transition which can profoundly affect the evolution of a surrounding planetary system. The timescale of dynamical planet evolution and orbital decay has important implications for planetary habitability, as well as post-main-sequence star and planet interaction, evolution, and internal structure. Here, we investigate these effects by estimating planet occurrence around 2476 low-luminosity red giant branch (LLRGB) stars observed by the NASA K2 mission. We measure stellar masses and radii using asteroseismology, with median random uncertainties of 3.7% in mass and 2.2% in radius. We compare this planet population to the known population of planets around dwarf Sun-like stars, accounting for detection efficiency differences between the stellar populations. We find that 0.49%+/-0.28% of LLRGB stars host planets larger than Jupiter with orbital periods less than 10 days, tentatively higher than main-sequence stars hosting similar planets (0.15%+/-0.06%). Our results suggest that the effects of stellar evolution on the occurrence of close-in planets larger than Jupiter are not significant until stars have begun ascending substantially up the red giant branch (>~5-6 R_{sun}_).
- ID:
- ivo://CDS.VizieR/I/96
- Title:
- Astrographic Catalogue, +01 to +31 Degrees
- Short Name:
- I/96
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This machine-readable version of the Astrographic Catalogue (AC), zones +01 to +31 degrees is the result of the determination of mean values for position and magnitude at a mean epoch of observation for each unique star in the original catalogs. The zones considered here (Oxford, Paris, Bordeaux, Toulouse, Algiers [partial]) contained 1,870,976 individual measures, from which the catalog of mean data for 1,025,208 stars was derived. Further analysis by Dr. D.W. Dunham and at the ADC yielded an additional 27897 apparently duplicate entries, which were eliminated to produce the final catalog. The estimated mean standard errors for positional and magnitude data are 0.4 arcsec in each coordinate and 0.4 mag, respectively. Data in this version include <m(pg)>, <Epoch>, <RA> at mean epoch, <DEC> at mean epoch. The mean values are unweighted. No star identifications are provided; hence the user must select stars from the catalog and then identify them in other catalogs or on charts using the equatorial coordinates.
- ID:
- ivo://CDS.VizieR/J/A+A/624/A145
- Title:
- Astrometric Catalogue 5, LQAC-5
- Short Name:
- J/A+A/624/A145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In addition to their great astrophysical interest, quasars represent quasi-ideal reference objects in the celestial sphere with, a priori, a lack of significant proper motion. Since the fourth release of the Large Quasar Astrometric Catalogue (LQAC-4), a large number of quasars have been discovered, in particular those coming from the DR14Q release of the SDSS. With the advent of the Gaia Data Release 2 (DR2), it is now also possible to fold in extremely accurate quasar positions. Following the same procedure as in the previous releases of the LQAC, our aim is to compile the large majority of the recorded quasars, with their best estimated coordinates and substantial information about their physical properties such as the redshift, multi-bands apparent, and absolute magnitudes. Emphasis is given to the results of the cross-matches with the Gaia DR2 catalogue, which considerably increases the positional accuracy. New quasars from the SDSS DR14Q release were cross-matched with the precedent LQAC-4 compilation with a 1" search radius, which leads to 149084 objects not present in the previous LQAC-4 release. Another cross-match was done with the Gaia DR2 catalogue, which enables us to considerably improve the positioning of these objects. For the first time, parallaxes and proper motions from the DR2, when available, are added to our compilation. Furthermore, a cross-identification of the LQAC-5 with the AllWISE survey gives additional mid-infrared information for an important percentage of objects. Our final catalogue, namely the LQAC-5, contains 592 809 quasars. This represents roughly a 34% increase with respect to the number of objects recorded in the LQAC-4. Among them, 398 697 objects were found in common with the Gaia DR2, within a 1" search radius. That corresponds to 67.26% of the whole population of the compilation. The LQAC-5 delivers a nearly complete catalogue of spectroscopically confirmed quasars (including a small proportion of 14126 compact AGN's) to the astronomical community, with the aim of giving their best equatorial coordinates with respect to the ICRF2 and with exhaustive additional information. For more than 50% of the sample, these coordinates are extracted from the very recent Gaia DR2.
- ID:
- ivo://CDS.VizieR/I/338
- Title:
- Astrometric catalogue of stars KMAC3
- Short Name:
- I/338
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of astrometric observations of faint V<17mag stars obtained with the Kyiv meridian axial circle. Observations were carried out in 2010-2015 in a declination zone of +2 +5.5 degrees and with use of Johnson V-band filter. The catalogue contains data for about 2 million of stars.
- ID:
- ivo://CDS.VizieR/I/332
- Title:
- Astrometric catalogue of stars KMAC2
- Short Name:
- I/332
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of astrometric observations of faint V<17mag stars obtained with the Kyiv meridian axial circle. Observations were carried out in 2001-2005 in a declination zone of 0+2 degrees and with use of Johnson V-band filter. The catalogue contains data for about a million of stars.
- ID:
- ivo://CDS.VizieR/J/other/KFNT/34.270
- Title:
- 2292 astrometric positions of asteroids
- Short Name:
- J/other/KFNT/34.
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- A catalogue of equatorial coordinates and magnitudes for 2162 asteroids and 11 comets was compiled based on the results of processing of digitized photographic observations of the northern sky performed in 1981-1985. The positions were compared with the JPL DE431 ephemeris. The mean (O-C)_RA,DE_ values for all positions obtained in this comparison are -0.08" and 0.04", and their root-mean-square errors are 0.70" and 0.64" in {alpha} and {delta}, respectively. It was found that the observations of 54 asteroids predate their discoveries, and the observations of four of them are the earliest known for these asteroids.
- ID:
- ivo://CDS.VizieR/J/AJ/152/111
- Title:
- A 2011-2013 survey of trans-Neptunian objects
- Short Name:
- J/AJ/152/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The trans-Neptunian objects (TNOs) preserve evidence of planet building processes in their orbital and size distributions. While all populations show steep size distributions for large objects, a relative deficit of Neptunian trojans and scattering objects with diameters of D<100km has been detected. We investigated this deficit with a 32 square degree survey, in which we detected 77 TNOs that are brighter than a limiting r-band magnitude of 24.6. Our plutino sample (18 objects in 3:2 mean-motion resonance with Neptune) shows a deficit of D<100km objects, rejecting a single power-law size distribution at >99% confidence. Combining our survey with the Canada-France Ecliptic Plane Survey, we perform a detailed analysis of the allowable parameters for the plutino size distribution, including knees and divots. We surmise the existence of 9000+/-3000 plutinos with an absolute magnitude of H_r_{<=}8.66 and 37000_-10000_^+12000^ with H_r_{<=}10.0 (95% confidence). Our survey also discovered one temporary Uranian trojan, one temporary Neptunian trojan, and one stable Neptunian trojan, for which we estimate populations of 110_-100_^+500^, 210_-200_^+900^, and 150_-140_^+600^ with H_r_{<=}10.0, respectively. All three populations are thus less numerous than the main belt asteroids (592 asteroids with H_r_{<=}10.0). With such population sizes, the temporary Neptunian trojans cannot be previously stable trojans diffusing out of the resonance now; they must be recently captured Centaurs or scattering objects. As the bias against the detection of objects grows with larger semimajor axes, our discovery of three 3:1 resonators and one 4:1 resonator adds to the growing evidence that the high-order resonances are far more populated than is typically predicted.
