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We present a new non-convex model of the 90 Antiope binary asteroid, derived with a modified version of the SAGE (Shaping Asteroids with Genetic Evolution) method using disk-integrated photometry only. A new variant of the SAGE algorithm capable of deriving models of binary systems is described. The model of 90 Antiope confirms the system's pole solution ($\lambda=199^{\circ}$, $\beta=38^{\circ}$, $\sigma=\pm5^{\circ}$) and the orbital period ($16.505046 \pm 0.000005$ h). A comparison between the stellar occultation chords obtained during the 2011 occultation and the projected shape solution has been used to scale the model. The resulting scaled model allowed us to obtain the equivalent radii ($R_{1}=40.4\pm0.9$ km and $R_{2}=40.2\pm0.9$ km) and the distance between the two system components ($176\pm4$ km), leading to a total system mass of ($9.14\pm0.62$)$\cdot10^{17}$ kg. The non-convex shape description of the components permitted a refined calculation of the components' volumes, leading to a density estimation of $1.67\pm0.23$ g cm$^{-3}$. The intermediate-scale features of the model may also offer new clues on the components' origin and evolution.

International audience; CCD photometry of 809 Lundia obtained between September 2005 and January 2006 at Borowiec and Pic du Midi Observatories demonstrates that this object is a synchronous binary system with an orbital period of 15.418 ± 0.001 h. In this paper, we present the results of photometric observations of Lundia from two oppositions in 2005/2006 and 2007, as well as the first modelling of the system. For simplicity we assumed a fluid-like nature for each component with a modified Roche model and a triaxial ellipsoid shape in kinematic models. Our models provided similar results. Poles of the orbit in ecliptic coordinates are lambda = 119 ± 2°, beta = 28 ± 4° (modified Roche) or lambda = 120 ± 5°, beta = 18 ± 12° (kinematic). Triaxial ellipsoid shape solutions and a separation between components of 15.8 km are given after taking an equivalent diameter of 9.1 km from H = 11.8 mag and assuming an albedo of 0.4. The orbital period of the Lundia system obtained from modelling is the same as from the lightcurve analysis i.e., 15.418 ± 0.001 h. The bulk density of both components is 1.64 or 1.71 ± 0.01 g/cm^3. The double system of Lundia probably originates from the fission process of a single body that could have been spun up by the YORP effect. The predicted lightcurves for future oppositions are also presented.

We present a set of new photometric observations of three main belt asteroids: 160 Una, 747 Winchester, and 849 Ara. This, combined with the available data, allowed us to construct their physical models. The lightcurve inversion method was used to obtain their spins and shapes. We have resolved problems with the rotation period of 160 Una, and found it to be 11.033176 ± 0.000011 h, almost twice the value given in the literature.

In 2007, the M-type binary asteroid 22 Kalliope reached one of its annual equinoxes. As a consequence, the orbit plane of its small moon, Linus, was aligned closely to the Sun's line of sight, giving rise to a mutual eclipse season. A dedicated international campaign of photometric observations, based on amateur-professional collaboration, was organized and coordinated by the IMCCE in order to catch several of these events. The set of the compiled observations is released in this work. We developed a relevant model of these events, including a topographic shape model of Kalliope refined in the present work, the orbit solution of Linus as well as the photometric effect of the shadow of one component falling on the other. By fitting this model to the only two full recorded events, we derived a new estimation of the equivalent diameter of Kalliope of 166.2+/-2.8km, 8% smaller than its IRAS diameter. As to the diameter of Linus, considered as purely spherical, it is estimated to 28+/-2 km. This substantial "shortening" of Kalliope gives a bulk density of 3.35+/-0.33g/cm3, significantly higher than past determinations but more consistent with its taxonomic type. Some constraints can be inferred on the composition., 59 pages, 8 tables, 15 figures submitted to Icarus

We present photometric observations of three asteroids: 73 Klytia, 377 Campania, and 378 Holmia, together with their spin and shape models. The models were constructed with the lightcurve inversion method, using all available lightcurves of these objects. In the case of Campania, the long persisting doubts about its rotational period have been resolved. Various authors state periods between 8.48 and 16 h, while the period we determined is 11.664401 ± 0.000010 h.

Photometric observations of 283 Emma (1998, 2000, 2001, 2004), 665 Sabine (1998, 1999, 2001, 2004, 2005), and 690 Wratislavia (1998, 2000, 2004, 2005-2006) carried out on 44 nights at two observatories are presented. Using all available lightcurves, the spin vectors, senses of rotation, and shape models for these three asteroids have been determined.

Context. The shapes and spin states of asteroids observed with photometric techniques can be reconstructed using the lightcurve inversion method. The resultant models can then be confirmed or exploited further by other techniques, such as adaptive optics, radar, thermal infrared, stellar occultations, or space probe imaging.Aims. During our ongoing work to increase the set of asteroids with known spin and shape parameters, there appeared a need for displaying the model plane-of-sky orientations for specific epochs to compare models from different techniques. It would also be instructive to be able to track how the complex lightcurves are produced by various asteroid shapes.Methods. Basing our analysis on an extensive photometric observational dataset, we obtained eight asteroid models with the convex lightcurve inversion method. To enable comparison of the photometric models with those from other observing/modelling techniques, we created an on-line service where we allow the inversion models to be orientated interactively.Results. Our sample of objects is quite representative, containing both relatively fast and slow rotators with highly and lowly inclined spin axes. With this work, we increase the sample of asteroid spin and shape models based on disk-integrated photometry to over 200. Three of the shape models obtained here are confirmed by the stellar occultation data; this also allowed independent determinations of their sizes to be made.Conclusions. The ISAM service can be widely exploited for past and future asteroid observations with various, complementary techniques and for asteroid dimension determination.

International audience; We analyze photometric observations of the three main-belt asteroids 350 Ornamenta, 771 Libera, and 984 Gretia, conducted over a twelve-year interval. Our data and those of other authors allow us to determine pole and shape models using the lightcurve inversion technique. In all three cases, a single pole solution was obtained without any significant mirror solution: Ornamenta - P = 9.180 414 h, lambdap = 184°, betap = -29° Libera - P = 5.890 423 h, lambdap = 64°, betap = -78° Gretia - P = 5.778 025 h, lambdap = 245°, betap = +52°. This analysis and the development of asteroid models increase the set of asteroids with known spin and shape parameters, which consists of only around 100 objects.

International audience; We report photometric lightcurve observations of 184 Dejopeja (apparition years: 2000, 2002, 2005, 2006), 276 Adelheid (2000, 2001, 2004, 2005, 2006), and 556 Phyllis (1998, 2000, 2002, 2004, 2005, 2006) carried out on 48 nights at four observatories. Using all of the available lightcurves, the spin vectors, senses of rotation, and shape models of these three asteroids have been determined.

The Global Astronomical Telescope System is a project managed by the Astronomical Observatory Institute of Adam Mickiewicz University in Poznań (Poland) and it is primarily intended for stellar medium/high resolution spectroscopy. The system will be operating as a global network of robotic telescopes. The GATS consists of two telescopes: PST 1 in Poland (near Poznań) and PST 2 in the USA (Arizona). The GATS project is also intended to cooperate with the BRITE satellites and supplement their photometry with spectroscopic observations.

Context. The set of more than 100 asteroids, for which spin parameters have been modelled using an amplitude, magnitude or epoch methods, showed a pronounced gap in the distribution of the asteroid spin axes. These spin axes are rarely aligned with the ecliptic plane. Aims. The number of asteroids with known spin parameters should be increased to allow for statistical investigations. Methods. We gathered extensive photometric datasets on four selected main-belt asteroids to model their spin and shape parameters using the lightcurve inversion method. Our only criterion of selection was their observability for small telescopes. Results. All four of the modelled asteroids happened to have rotational poles that lie close to the ecliptic plane (periods and J2000 north pole coordinates): (94) Aurora − P = 7.226191 h, λp1 = 58 ◦ , βp1 =+ 16 ◦ ; λp2 = 242 ◦ , βp2 =+ 4 ◦ ; (174) Phaedra − P = 5.750249 h, λp = 265 ◦ , βp =+ 5 ◦ ; (679) Pax − P = 8.456016 h, λp1 = 42 ◦ , βp1 = −5 ◦ ; λp2 = 220 ◦ , βp2 =+ 32 ◦ (pole 2 preferred after comparison with AO-resolved observations); (714) Ulula − P = 6.998376 h, λp1 = 42 ◦ , βp1 = −9 ◦ ; λp2 = 227 ◦ , βp2 = −14 ◦ . Conclusions. This work suggests that asteroid spin axes do not avoid the ecliptic plane, contrary to what the classical modelling suggested.

Context. Earlier work suggests that slowly rotating asteroids should have higher thermal inertias than faster rotators because the heat wave penetrates deeper into the subsurface. However, thermal inertias have been determined mainly for fast rotators due to selection effects in the available photometry used to obtain shape models required for thermophysical modelling (TPM). Aims. Our aims are to mitigate these selection effects by producing shape models of slow rotators, to scale them and compute their thermal inertia with TPM, and to verify whether thermal inertia increases with the rotation period. Methods. To decrease the bias against slow rotators, we conducted a photometric observing campaign of main-belt asteroids with periods longer than 12 h, from multiple stations worldwide, adding in some cases data from WISE and Kepler space telescopes. For spin and shape reconstruction we used the lightcurve inversion method, and to derive thermal inertias we applied a thermophysical model to fit available infrared data from IRAS, AKARI, and WISE. Results. We present new models of 11 slow rotators that provide a good fit to the thermal data. In two cases, the TPM analysis showed a clear preference for one of the two possible mirror solutions. We derived the diameters and albedos of our targets in addition to their thermal inertias, which ranged between 3(-3)(+33) and 45(-30)(+60) Jm(-2) s(-1/2) K-1. Conclusions. Together with our previous work, we have analysed 16 slow rotators from our dense survey with sizes between 30 and 150 km. The current sample thermal inertias vary widely, which does not confirm the earlier suggestion that slower rotators have higher thermal inertias.© ESO 2019, This work was supported by the National Science Centre, Poland, through grant no. 2014/13/D/ST9/01818. The research leading to these results has received funding from the European Union's Horizon 2020 Research and Innovation Programme, under Grant Agreement no 687378 (SBNAF). The research of V.K. was supported by a grant from the Slovak Research and Development Agency, number APVV-15-0458. R. D. acknowledges financial support from the State Agency for Research of the Spanish MCIU through the >Center of Excellence Severo Ochoa> award for the Instituto de Astrofisica de Andalucia(SEV-2017-0709). The Joan Oro Telescope (TJO) of the Montsec Astronomical Observatory (OAdM) is owned by the Catalan Government and operated by the Institute for Space Studies of Catalonia (IEEC). This article is based on observations made in the Observatorios de Canarias del IAC with the 0.82 m IAC80 telescope operated on the island of Tenerife by the Instituto de Astrofisica de Canarias (IAC) in the Observatorio del Teide. This article is based on observations made with the SARA telescopes (Southeastern Association for Research in Astronomy), whose nodes are located at the Observatorios de Canarias del IAC on the island of La Palma in the Observatorio del Roque de los Muchachos; Kitt Peak, AZ under the auspices of the National Optical Astronomy Observatory (NOAO); and Cerro Tololo Inter-American Observatory (CTIO) in La Serena, Chile. This project uses data from the SuperWASP archive. The WASP project is currently funded and operated by Warwick University and Keele University, and was originally set up by Queen's University Belfast, the Universities of Keele, St. Andrews, and Leicester, the Open University, the Isaac Newton Group, the Instituto de Astrofisica de Canarias, the South African Astronomical Observatory, and by STFC. Funding for the Kepler and K2 missions is provided by the NASA Science Mission Directorate. The data presented in this paper were obtained from the Mikulski Archive for Space Telescopes (MAST). STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. Support for MAST for non-HST data is provided by the NASA Office of Space Science via grant NNX09AF08G and by other grants and contracts. This publication makes use of data products from theWide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. The research leading to these results has received funding from the LP2012-31 and LP2018-7/2018 Lendulet grants of the Hungarian Academy of Sciences.