- ID:
- ivo://CDS.VizieR/VII/288
- Title:
- Asteroid phase curve coefficients from ATLAS observations
- Short Name:
- VII/288
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Asteroid phase curves are used to derive fundamental physical properties through the determination of the absolute magnitude H. The upcoming visible Legacy Survey of Space and Time (LSST) and mid-infrared Near-Earth Object Surveillance Mission (NEOSM) surveys rely on these absolute magnitudes to derive the colours and albedos of millions of asteroids. Furthermore, the shape of the phase curves reflects their surface compositions, allowing for conclusions on their taxonomy. We derive asteroid phase curves from dual-band photometry acquired by the Asteroid Terrestrial-impact Last Alert System telescopes. Using Bayesian parameter inference, we retrieve the absolute magnitudes and slope parameters of 127012 phase curves of 94777 asteroids in the photometric H, G1, G2- and H, G12*-systems. The taxonomic complexes of asteroids separate in the observed G1, G2-distributions, correlating with their mean visual albedo. This allows for differentiating the X-complex into the P-, M-, and E-complexes using the slope parameters as alternative to albedo measurements. Further, taxonomic misclassifications from spectrophotometric datasets as well as interlopers in dynamical families of asteroids reveal themselves in G1, G2-space. The H, G12*-model applied to the serendipitous observations is unable to resolve target taxonomy. The G1, G2 phase coefficients show wavelength-dependency for the majority of taxonomic complexes. Their values allow for estimating the degree of phase reddening of the spectral slope. The uncertainty of the phase coefficients and the derived absolute magnitude is dominated by the observational coverage of the opposition effect rather than the magnitude dispersion induced by the asteroids' irregular shapes and orientations. Serendipitous asteroid observations allow for reliable phase curve determination for a large number of asteroids. To ensure that the acquired absolute magnitudes are suited for colour computations, it is imperative that future surveys densely cover the opposition effects of the phase curves, minimizing the uncertainty on H. The phase curve slope parameters offer an accessible dimension for taxonomic classification, correlating with the albedo and complimentary to the spectral dimension.
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- ID:
- ivo://CDS.VizieR/J/other/CoSka/33.159
- Title:
- Asteroid positions in 2002
- Short Name:
- J/other/CoSka/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The paper presents the results of position determinations of minor planets carried out at the Skalnate Pleso Observatory in the year 2002. 109 CCD observations of 21 minor planets are given together with the list of reference stars.
- 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/A+A/338/340
- Title:
- Asteroids as IR Standards for ISOPHOT
- Short Name:
- J/A+A/338/340
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Asteroids are used as far-IR calibrators for the imaging photopolarimeter ISOPHOT on board the Infrared Space Observatory ISO. For the 10 selected objects we compiled a large uniform database of 678 individual observations, ranging from 7-2000{mu}m. Applying a new thermophysical model to the observations we derived thermal properties of the selected asteroids, based on spin-vector solutions, direct size measurements and the HG-magnitude system. Our investigations indicate very rough surfaces, reflected in the beaming effect, and very low levels of heat conduction, expressed in thermal inertias between 5 and 25J/m^2^/s^0.5^/K. Due to scattering processes in the porous regolith, the emissivity varies significantly with wavelength. In case of Vesta we find emissivities as low as 0.6 in the far-IR/submillimetre region. By entering the combined results into the thermophysical model we defined new photometric standards for the far-IR. The absolute accuracy for thermal flux or lightcurve predictions is 5-10% for the first category objects and 10-20% for the secondaries. The methods and procedures discussed here are included in the first update of the ISOPHOT calibration in 1998.
- ID:
- ivo://CDS.VizieR/J/A+A/572/A29
- Title:
- Asteroids for a targeted spectroscopic survey
- Short Name:
- J/A+A/572/A29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Asteroid spectroscopy reflects surface mineralogy. There are few thousand asteroids whose surfaces have been observed spectrally. Determining the surface properties of those objects is important for many practical and scientific applications, such as for example developing impact deflection strategies or studying history and evolution of the Solar System and planet formation. The aim of this study is to develop a pre-selection method that can be utilized in searching for asteroids of any taxonomic complex. The method could then be utilized im multiple applications such as searching for the missing V-types or looking for primitive asteroids. We used the Bayes Naive Classifier combined with observations obtained in the course of the Sloan Digital Sky Survey and the Wide-field Infrared Survey Explorer surveys as well as a database of asteroid phase curves for asteroids with known taxonomic type. Using the new classification method we have selected a number of possible V-type candidates. Some of the candidates were than spectrally observed at the Nordic Optical Telescope and South African Large Telescope. We have developed and tested the new pre-selection method. We found three asteroids in the mid/outer Main Belt that are likely of differentiated type. Near-Infrared are still required to confirm this discovery. Similarly to other studies we found that V-type candidates cluster around the Vesta family and are rare in the mid-to-outer Main Belt. The new method shows that even largely explored large databases combined together could still be further exploited in for example solving the missing dunite problem.
- ID:
- ivo://CDS.VizieR/VII/108C
- Title:
- Asteroids II Machine-Readable Data Base
- Short Name:
- VII/108C
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This data set was assembled by E. F. Tedesco, Jet Propulsion Laboratory, in March 1988 from files provided by the contributors to the above reference. Included are asteroid names and discovery circumstances, proper elements and family identifications, asteroid lightcurve parameters, asteroid pole determinations, taxonomic classes, absolute magnitudes and slope parameters, UBV color indices, and albedos and diameters from the IRAS Asteroid and Comet Survey. The asteroid discovery tables were updated by F. Pilcher in 1994.
1297. Asteroids in GALEX
- ID:
- ivo://CDS.VizieR/J/ApJ/809/92
- Title:
- Asteroids in GALEX
- Short Name:
- J/ApJ/809/92
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present ultraviolet (UV) photometry (near-UV (NUV) band, 180-280nm) of 405 asteroids observed serendipitously by GALEX from 2003 to 2012. All asteroids in this sample were detected by GALEX at least twice. Unambiguous visible-color-based taxonomic labels (C type versus S type) exist for 315 of these asteroids; of these, thermal-infrared-based diameters are available for 245. We derive NUV-V color using two independent models to predict the visual magnitude V at each NUV-detection epoch. Both V models produce NUV-V distributions in which the S types are redder than C types with more than 8{sigma} confidence. This confirms that the S types' redder spectral slopes in the visible remain redder than the C types' into the NUV, this redness being consistent with absorption by silica-containing rocks. The GALEX asteroid data confirm earlier results from the International Ultraviolet Explorer, which two decades ago produced the only other sizeable set of UV asteroid photometry. The GALEX-derived NUV-V data also agree with previously published Hubble Space Telescope (HST) UV observations of asteroids 21 Lutetia and 1 Ceres. Both the HST and GALEX data indicate that NUV band is less useful than u band for distinguishing subgroups within the greater population of visible-color-defined C types (notably, M types and G types).
- ID:
- ivo://CDS.VizieR/J/A+A/556/A8
- Title:
- 100 asteroids rotational parameters
- Short Name:
- J/A+A/556/A8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compute for a set of 100 asteroids their rotational parameters: the moments of inertia along the principal axes of the object, the obliquity of the axis of rotation with respect to the orbital plane, the precession rates, and the nutation coefficients. We select 100 asteroids for which the parameters for the study are well-known from observations or space missions. For each asteroid, we determine the moments of inertia, assuming an ellipsoidal shape. We calculate their obliquity from their orbit (instead of the ecliptic) and the orientation of the spin-pole. Finally, we calculate the precession rates and the largest nutation components. The number of asteroids concerned leads to some statistical studies of the output. We provide a table of rotational parameters for our set of asteroids. The table includes the obliquity, their axes ratio, their dynamical ellipticity H_d_, and the scaling factor K. We compute the precession rate {psi} and the leading nutation coefficients {Delta}{psi} and {Delta}{epsilon}. We observe similar characteristics, as observed by previous authors that is, a significantly larger number of asteroids rotates in the prograde mode (~60%) than in the retrograde one with a bimodal distribution. In particular, there is a deficiency of objects with a polar axis close to the orbit. The precession rates have a mean absolute value of 18"/y, and the leading nutation coefficients have an average absolute amplitude of 5.7" for {Delta}{psi} and 5.2" for {Delta}{epsilon}. At last, we identify and characterize some cases with large precession rates, as seen in 25143 Itokawa, with has a precession rate of about - 475"/y.
- ID:
- ivo://CDS.VizieR/J/A+A/506/79
- Title:
- Asteroseismic analysis of HD 174936
- Short Name:
- J/A+A/506/79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the {delta}-Scuti star HD 174936 (ID 7613) observed by CoRoT during the first short run SRc01 (27 days). A total number of 422 frequencies were extracted from the light curve using standard prewhitening techniques. This number of frequencies was obtained by considering a spectral significance limit of sig=10 using the software package SigSpec. Our analysis of the oscillation frequency spectrum reveals a spacing periodicity around 52muHz. Although modes considered here are not in the asymptotic regime, a comparison with stellar models confirms that this signature may stem from a quasi-periodic pattern similar to the so-called large separation in solar-like stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/838/115
- Title:
- Asteroseismic analysis of 8 Kepler red giants
- Short Name:
- J/ApJ/838/115
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using data from the NASA spacecraft Kepler, we study solar-like oscillations in red giant stars in the open cluster NGC 6811. We determine oscillation frequencies, frequency separations, period spacings of mixed modes, and mode visibilities for eight cluster giants. The oscillation parameters show that these stars are helium-core-burning red giants. The eight stars form two groups with very different oscillation power spectra; the four stars with the lowest {Delta}{nu} values display rich sets of mixed l=1 modes, while this is not the case for the four stars with higher {Delta}{nu}. For the four stars with lowest {Delta}{nu}, we determine the asymptotic period spacing of the mixed modes, {Delta}P, which together with the masses we derive for all eight stars suggest that they belong to the so-called secondary clump. Based on the global oscillation parameters, we present initial theoretical stellar modeling that indicates that we can constrain convective-core overshoot on the main sequence and in the helium-burning phase for these ~2M_{sun}_ stars. Finally, our results indicate less mode suppression than predicted by recent theories for magnetic suppression of certain oscillation modes in red giants.
