<p>We have performed numerical simulations of narrow rings around small bodies, addressing both the m=2 resonance perturbations induced by a rotating tri-axial ellipsoidal central body and the m=1 perturbations due to a mass anomaly on the surface of the central body.  The simulations include up to 1e5 mutually colliding particles, and their partially inelastic impacts are resolved with the soft-sphere treatment introduced in Salo (1995; for details see Salo et al. 2018). An azimuthally complete ring is followed, and the integrations are performed in an inertial center-of-mass frame, lasting up to 1e5 central body rotations. Our goal is to see under which conditions the perturbation may prevent the collision-induced viscous spreading of the ring, instead leading to a confinement.</p> <p>Our study is motivated by the narrow dense rings discovered around the tri-axial Centaur object Chariklo (Braga-Ribas et al. 2014) and the dwarf planet Haumea (Ortiz et al. 2017). In particular the Chariklo ring consists of two narrow components, with the inner ring having an optical depth of the order of unity and possessing sharp edges. While the ellipticity of the ring is poorly constrained (measurements are consistent with a circular ring), it is known to exhibit substantial width variations (Berard et al. AJ, 154, 144). Both Chariklo and Haumea rings are close to a distance where the orbital period equals three central body rotations, corresponding to a 2/6 resonance with a rotating ellipsoidal body, and a 1/3 resonance for a mass anomaly (Sicardy et al. 2019).</p> <p>Sicardy et al. (2019) demonstrated that torques connected to resonances lead to a rapid clearing of particles from the vicinity of the central body, up to distances where orbital period equals two central body rotation periods.  Their test particle calculations approximated the effects of impacts with an additional Stokes friction term.  Our realistic collisional simulations confirm these results, and also indicate that the m=2 perturbation by the ellipsoidal body has an insignificant effect at the 2/6 resonance. On the other hand, we find that a sufficiently strong mass anomaly may eventually lead to formation of a narrow confined ring near 1/3  (Fig. 1).</p> <p>What maintains the ring confined?  Our favored mechanism is the reversal of angular momentum flux.  Without perturbation, the outward flow of angular momentum, together with collisional dissipation, always implies radial dispersal of a narrow ring. However, in a strongly perturbed ring (say with an eccentricity gradient related to width variations) the direction of flux may reverse, leading to a confinement of sharp edges (Borderies et al. 1982).  In Hänninen and Salo (1994, 1995; see also Goldreich et al 1995) such a confinement was verified in direct simulations of first order satellite Lindblad resonances, including the inner 2/1 (ILR) and outer 1/2 (OLR). Moreover, the<br />simulation-measured pressure tensor was shown to be in accordance with the theoretical mechanism.  With the current code we have verified this early simulation result, and extended similar measurements to the 1/3 case.  However, the 1/3 behaviour is more complicated due to the different order of the resonance.  While in the ILR and OLR resonances the response of the ring is more or less steady in the frame rotating with the perturber, this is not so in the 1/3 case.</p> <p><br />We are currently investigating in detail the confinement/ flux reversal mechanism, which results will be reported.  We will also discuss the scaling between the simulated particle size and the magnitude of the mass anomaly required for confinement.  Eventually,  in order to extend the calculations to realistic particle sizes, a larger number of particles needs to be simulated in a multi-processor environment: for that purpose we plan to use the new REBOUND-based soft-sphere code recently applied to local simulations of viscous overstability (Mondino-Llermanos and Salo, this meeting; submitted to MNRAS).  The soft-sphere impact treatment is important as the ringlets have a large optical depth; it will also facilitate the later inclusion of ring self-gravity, important for rings near the Roche zone where temporary clumping of particles is expected.</p> <p><img src="data:image/jpeg;base64, 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Trans-Neptunian Objects (TNOs) are thought to be among the least evolved Solar System objects, which retain information on the origin and evolution of the outer parts of it. They are located at far distances of the Sun, where the influence of our star is less dramatic than in the closer regions. Thus, these icy objects are extremely interesting bodies that hide plenty of information on the physical and dynamical processes thatshaped our Solar System.We only know a few retrograde TNOs so far (e.g. 2008 KV42 [1], 2011 KT19 [2], 2004 XR190). One of the few known retrograde objects listed in the MPC database as a scattered disk object is 2013 LU28, which has a high orbital eccentricity (e = 0.95), a large semimajor axis (a= 181 AU) and a very high inclination (i = 125.4º). This exotic object is also classified as an “extended centaur”, because its perihelion at 8.7 AU moves it into the centaur region.The physical properties of 2013 LU28, such as its rotational period and light curve amplitude, are unknown but can be revealed through photometry. With this aim, we observed this object during three observing runs on 2021 January and March using two telescopes, the 1.23 m telescope at Calar Alto Observatory in Almería, Spain and the 1.5 m telescope at Sierra Nevada Observatory in Granada, Spain. From these observations we derived the first determination of the rotational light curve of 2013LU28 from which we derived its rotational period and its peak-to-peak light curve amplitude. The obtained amplitude turned out to be higher than the average amplitude of most TNOs, which points toward an elongated or a binary object. Other magnitudes, such as its absolute magnitude (H) were also derived. We will present and discuss preliminary results on all the above.AcknowledgementsThe authors acknowledge financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). P.S-S. acknowledges financial support by the Spanish grant AYA-    RTI2018-098657-J-I00 "LEO-SBNAF" (MCIU/AEI/FEDER, UE). We are grateful to the CAHA and OSN staffs. This research is partially based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by Junta de Andalucı́a and Consejo Superior de Investigaciones Cientı́ficas (IAA-CSIC). This research was also partially based on observation carried out at the Observatorio de Sierra Nevada  (OSN) operated by Instituto de Astrofı́sica de Andalucı́a (CSIC).Bibliography[1] B. Gladman, J. Kavelaars, J.-M. Petit, M. L. N. Ashby, J. Parker, J. et al. ApJ 697:L91–L94, 2009[2] Ying-Tung Chen , Hsing Wen Lin, Matthew J. Holman, Matthew J. Payne et al. ApJ 827:L24 (5pp), 2

Two stellar occultations by the largest satellite of the dwarf planet Haumea, Hi'iaka, were predicted to happen on April, 6th and 16th, 2021. Additional high accuracy astrometric analysis was carried out in order to refine the prediction for April 6th, using several telescopes in the 1.2-m to 2-m range, with the final shadow path crossing North Africa. We successfully detected the first event from TRAPPIST-North telescope at Oukaïmeden Observatory (Morocco). Although it was recorded from only one site, this first detection allowed us to improve the prediction for the second that crossed North America from East to West. We had a good success recording six positive detections and several negative detections that constrain the shape and size of the body. The light curves obtained from the different observatories provide the time at which the star disappears and reappears, which are translated into chords (the projected lines on the sky-plane as observed from each location). Additionally, we carried out a campaign to study Hi'iaka's rotational light-curve, studying the residuals of Haumea's rotational light-curve to a four-order Fourier fit. We obtained the rotational phases at the times of the occultations, which is critical for the analysis of the occultations, given that Hi’iaka is clearly non-spherical. Our preliminary results show that Hi'iaka indeed has a triaxial shape with a larger effective diameter than what has been published so far. The preliminary results and their implications will be discussed in this talk. 

The investigation of Titan’s surface chemical composition is of great importance for the understanding of the atmosphere-surface-interior system of the moon. The Cassini cameras and especially the Visual and infrared Mapping Spectrometer has provided a sequence of spectra showing the diversity of Titan’s surface spectrum from flybys performed during the 13 years of Cassini’s operation. In the 0.8-5.2 μm range, this spectro-imaging data showed that the surface consists of a multivariable geological terrain hosting complex geological processes. The data from the seven narrow methane spectral “windows” centered at 0.93, 1.08, 1.27, 1.59, 2.03, 2.8 and 5 μm provide some information on the lower atmospheric context and the surface parameters. Nevertheless, atmospheric scattering and absorption need to be clearly evaluated before we can extract the surface properties. In various studies (Solomonidou et al., 2014; 2016; 2018; 2019; 2020a, 2020b; Lopes et al., 2016; Malaska et al., 2016; 2020), we used radiative transfer modeling in order to evaluate the atmospheric scattering and absorption and securely extract the surface albedo of multiple Titan areas including the major geomorphological units. We also investigated the morphological and microwave characteristics of these features using Cassini RADAR data in their SAR and radiometry mode. Here, we present a global map for Titan’s surface showing the chemical composition constraints for the various units. The results show that Titan’s surface composition, at the depths detected by VIMS, has significant latitudinal dependence, with its equator being dominated by organic materials from the atmosphere and a very dark unknown material, while higher latitudes contain more water ice. The albedo differences and similarities among the various geomorphological units give insights on the geological processes affecting Titan’s surface and, by implication, its interior. We discuss our results in terms of origin and evolution theories.

Within the Lucky Star international collaboration* on stellar occultations by TNOs and other outer solar system bodies, we predicted the occultation by the TNO (143707) 2003 UY117 of an mV ~ 14.6 mag star on 23 October 2020. Around a week before the occultation date, we updated and refined the prediction using high precision astrometry obtained using the 2 m Liverpool telescope located at El Roque de Los Muchachos Observatory on La Palma, Spain. The update resulted in a shadow path with good observability potential. We carried out a specific campaign involving 27 observing sites in the south of Spain and North of Africa to observe the occultation. We recorded 4 positive detections and several very close misses to the south of the body. With this information we determined the silhouette of 2003 UY117 at the moment of the occultation. We also obtained the geometric albedo and the size for this object. In addition to this, we carried out several photometric runs with large telescopes to determine the rotation period and rotational phase at the time of the occultation. The body presents a clear double-peaked rotational light curve consistent with a triaxial ellipsoid of considerable elongation, which means that a rotational light curve analysis is critical to correctly interpret the occultation results. The preliminary analysis indicates a larger equivalent diameter than that determined from Herschel thermal data, although consistent within the large error bars of the thermal determination. We will present the preliminary results and discuss their implications.*Lucky Star (LS) is an EU-funded research activity to obtain physical properties of distant Solar System objects using stellar occultations. LS collaboration agglomerates the efforts of the Paris, Granada, and Rio teams. https://lesia.obspm.fr/lucky-star/ Acknowledgements:JLO, PS-S, NM, MV, and RD acknowledge financial support from the State Agency for Research of the Spanish MCIU through the ‘Center of Excellence Severo Ochoa’ award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709), they also acknowledge the financial support by the Spanish grant AYA-2017-84637-R and AYARTI2018- 098657-J-I00 ‘LEO-SBNAF’ (MCIU/AEI/FEDER, UE).

The Centaur (10199) Chariklo is a small body moving in an elliptical orbit, between Saturn and Uranus, with heliocentric distances ranging 13.1 and 18.9 au. It is the largest object known in this orbital region, and since its discovery in 1997 (Ticha et al. 1997), many studies tried to characterise this object. From the literature, different observational techniques give an equivalent surface radius ranging between 109 and 151 km (Sekiguchi et al., 2012; Lellouch et al., 2017). Additionally, a ring system was detected by Braga-Ribas et al. (2014) using stellar occultation data sets acquired in 2013. Between 2013 and 2016, other stellar occultations brought more detailed information on this system (Bérard et al., 2017; Leiva et al., 2017).A stellar occultation occurs when a solar system object passes in front of a star for an observer on Earth. Using this technique it is possible to determine sizes and shapes at kilometre precision and to obtain other physical parameters, such as its albedo, the presence of an atmosphere, rings, jets, or topographic features (Braga-Ribas et al., 2013, 2019; Dias-Oliveira et al., 2015, 2017; Benedetti-Rossi et al., 2019; Ortiz et al., 2017; Leiva et al., 2017; Bérard et al., 2017; Santos-Sanz et al., 2021).After the release of the Gaia DR2 catalogue (Gaia collaboration et al., 2018), the stars' positions are known with uncertainties below one milliarcsecond (mas).  Moreover, after successful stellar occultations observations, Chariklo ephemeris was updated, now it has uncertainties below five mas ($\sim$50 km at Chariklo's distance). Accurate star's positions and updated ephemeris resulted in successful observational campaigns in Namibia (22/06/2017), South America (23/07/2017) and La Réunion (08/08/2019). These were the first Chariklo occultations with more than three chords across the main body. These events increased our knowledge about Chariklo's shape, and this information can be used to constrain the dynamic of its rings. Six other events were observed between 2017 and 2020, however with fewer detections on the main body.In this work, we will present the obtained results, such as the global shape of Chariklo's rings system, including its pole determination, the ring width variation, structures within the rings (see Figure 1), the width of the gap between C1R and C2R and limits for the ring eccentricity and particle's sizes. Also, the 3D shape of Chariklo was obtained from eleven stellar occultations observed between 2013 and 2020 (see Figure 2). The parameters obtained in this work should be useful for constraining dynamical models of Chariklo and its rings and provide new insights into the formation and evolution of this system.Figure 1: Results of the 2017-07-23 event. The central plot displays the occulting chords projected in the sky-plane for the main body (in blue), C1R (in green), and their uncertainties (red segments). The black line is the best-fitting ellipse to the C1R point. The side panels display the normalised radial ring profiles, projected in the ring-plane, numbered as follows: VLT at Cerro Paranal (1), Tolar Grande (2), La Silla (3), Observat\'orio Pico dos Dias (4) and Cerro Tololo (5). The observations on La Silla were made using the Danish telescope dual experiment in the Visual (3.1) and Red bands (3.2) and a 1-meter telescope (3.3). The observations on Cerro Tololo were grazing over C1R and they were made using the SARA (5.1) and PROMPT (5.2).  We call attention to the unambiguous detection of W-shaped structures within the C1R.Figure 2: Ellipsoidal model that best fits the 11 stellar occultations observed between 2013-06-23 and 2020-06-19. Each panel corresponds to an occultation event identified by the time stamp in the upper part of each one. The blue lines stand for the observed chords with their uncertainties in red. The black dot indicates the intersection between the equator and the prime meridian, which is used as the reference to define the rotation angle.

AbstractCentaurs and trans-Neptunian objects (TNOs) are considered to be the most pristine members of our solar system, beside Oort cloud objects.The observation of stellar occultations by solar system objects is a powerful technique to directly measure their size and profile shapes with kilometer accuracy [e.g. 1, and references therein], to probe the environment of them with the possibility to reveal satellites and / or rings [e.g. 2, 3] and to detect or to constrain an atmosphere down to the nanobar level [e.g. 4]. Finally it provides a high-accuracy astrometric measurement, which can for example be used for improving the prediction of subsequent occultation events within short or mid-term time spans.Here we report the observation of an occultation event of the star Gaia DR2 4111560308371475840 (G = 14.6 mag) by the TNO (119951) 2002 KX14 on May 26, 2020. The shadow was predicted to cross eastern Europe (Fig. 1) and the event was observed successfully by ten stations supplemented by another good dozen of stations which had a miss (no event detected).2002 KX14 is a low-inclination (i ~ 0.4°), low-eccentricity (e ~ 0.04) cold classical TNO, orbiting the Sun at an average distance of a ~ 39 au. The radiometric diameter is given as 455 ± 27 km [5]. On April 26, 2012, an occultation by this object was observed with the 4.2-m William Herschel Telescope on La Palma (Spain) at high cadence. From this single-chord observation (with a chord length of 415 ± 1 km), combined with accurate astrometry at the time of occultation, an area-equivalent diameter of at least 365 (+30, -21) km was estimated [6]. The rotational period is yet unknown. The lightcurve amplitude is reported as Δm 

Narrow and dense rings have been discovered around the small Centaur object Chariklo (Braga-Ribas et al 2014) and the dwarf planet Haumea (Ortiz et al. 2017). Both ring systems are observed close to the 1/3 resonance with the central body, meaning that the particles complete one revolution while the body completes three rotations.The potential of small bodies can have large non-axisymmetric terms when compared to the giants planets. As a result, strong resonant couplings occur between the body and a surrounding collisional, dissipative disk (Sicardy et al. 2019). Those resonances are described by a critical angle φ= mλ' - (m-j)λ - jϖ, where j>0 is the resonant order (i.e. the order in eccentricity of the resonant term in the Hamiltonian), m (m0) is the azimuthal number, λ' (resp. λ) is the rotational angle of the body (resp. the particle), and ϖ is the longitude of periapse of the particle.Among the j= 1 (Lindblad), 2, 3 and 4 resonances, only the cases j= 1 and 2 can have an unstable (more precisely non-elliptic) point at the origin of the phase portrait describing [X= e.cos(φ), Y= e.sin(φ)], where e is the eccentricity and φ is the critical angle previously defined. The 1/3 resonant in particular has m=-1  and j=2, and is thus of second order. For a narrow range of the Jacobi constant associated with that resonance [i.e. a - (3/2)a0e2, where a is the ring's semi-major axis and a0 is the semi-major axis at exact resonance], the origin of the phase portrait is hyperbolic, hence unstable.This instability triggers an eccentricity excitation of the ring near the 1/3 resonance, a source of torque on that ring. Such resonance can be created by a mass anomaly in the central body. We have tested this mechanism by simulating a ring with 30,000 particles undergoing inelastic collisions near the 1/3 resonance with Chariklo, in the presence of a large mass anomaly that represents 0.1 the mass of the body.    Preliminary results are shown in the figure above. The density of particles has been plotted in a (Jacobi constant-eccentricity) diagram, with the exact resonance location plotted as the vertical dash-dotted gray line. The solid gray line is the expected maximum eccentricity reached by particles for the corresponding Jacobi constant. Panel (a): initial conditions for the 30,000 ring particles; panel (b): the particles after 2,000 Chariklo rotations (about 1.6 years) during the excitation phase due to the 1/3 resonance; panel (c): the particles in the time interval 9,000-9,900 Chariklo rotations (~7-8 years). At that point, the ring has settled just outside the resonance location, reaching a balance between the eccentricity and semi-major dampings due to inelastic collisions, and the eccentricity excitation caused by the resonance. More quantitative results will be presented, in particular the effect of smaller, more realistic, mass anomalies, and the assessment of a possible slow outward drift caused by a residual secular torque on the ring. Meanwhile, the observed behavior in those simulations appears as a promising mechanism to explain the proximity of both Chariklo's and Haumea's rings to the 1/3 resonance. ReferencesBraga-Ribas et al. 2014, Nature 508, 72Ortiz et al. 2017, Nature 550, 219Sicardy et al. 2019, Nature Astronomy 3, 146Sicardy et al. 2020, in The Trans-Neptunian Solar System (Eds. D. Prialnik, M.A. Barucci and L. Young), Elsevier (Chapter 11) Acknowledgements. The work leading to these results has received funding from the European Research Council under the European Community's H2020 2014-2021 ERC Grant Agreement n°669416 "Lucky Star".  

Jupiter’s largest moon, Ganymede, is the main target of the upcoming ESA mission JUpiter ICy moons Explorer (JUICE), which is planned to launch in 2023. One of the top priorities of the JUICE mission is investigation of past and/or recent cryovolcanic and tectonic activity and the exchange processes with the subsurface and possibly with the ocean (Grasset et al., 2013). Following that objective, the science team has defined ‘potential cryovolcanic regions’ as a category of high interest for observation by JUICE (Stephan et al. 2021). Hence, for preparation of the scientific return of the mission, it is important to study in detail the regions that are considered to be good candidates for past or present activity.  Areas on Ganymede imaged by Voyager that showed the presence of dark terrain were speculated to represent a heavily cratered surface modified by cryovolcanism (e.g., Murchie et al., 1989); however, this was disputed based on the higher-resolution images of the Galileo mission (e.g., Pappalardo et al., 2004). Light material observed by the Voyager instruments was similarly suggested to represent dark terrain resurfaced by cryovolcanic flows (e.g., Parmentier et al., 1982). Later, Galileo high-resolution data showed the significant role of tectonism in the formation of these areas, while the role of cryovolcanism remained inconclusive due to the limited resolution of the available data and secondary processes that complicate their interpretation, such as fracturing, mass wasting, etc (e.g., Patterson et al., 2010). Currently, small, isolated depressions called ‘paterae’, are the best candidate regions for cryovolcanic activity on Ganymede and suggested to be potential caldera-like cryovolcanic source vents (Fig. 1;2)(e.g., Lucchita, 1980; Spaun et al. 2001). Collins et al. (2013) characterize the paterae as ‘flat-floored depressions surrounded by inward-scalloped walls, breached on one side and typically associated with light subdued materials’ while they interpret their nature as ‘possible cryovolcanic source vents for extrusion of clean icy material to form light material units’. The small size of paterae (20 x 70 km at most) is consistent with a cryovolvanic origin that operates on a local scale.The high-resolution JUICE camera, JANUS, in combination with other remote sensing instruments, is expected to resolve many of the mysteries concerning cryovolcanism on Ganymede and the origin of the moon’s varied geologic features. The known paterae (Fig. 1) are located in smooth and bright terrains, where extensional tectonism and volcanism are speculated to have operated concurrently (Pappalardo et al. 2004). The ‘potential cryovolcanic regions’ identified by the JUICE team includes 19 out of 30 paterae mapped by Collins et al. (2013) using Voyager and Galileo images. In this study, we provide a thorough view of all 19 paterae regions and a constructional comparison of their characteristics in order to constrain the morphology of the paterae and their surroundings, in preparation of the JUICE mission and its science return.Figure 1. Locations (red circles and ellipsoids) of 19 paterae identified as ‘potential cryovolcanic regions’ that are of high interest for JUICE observations (Stephan et al. 2021). Basemap: Galileo Solid State Imaging (SSI)/Voyager Imaging Science Subsystem (ISS) mosaic.Figure 2. Major Ganymede Paterae as observed from the Voyager and Galileo instruments: a. Hammamat (1 in Fig. 1); b. Musa (4); c. Rum (2); d. Yaroun (5); e. Hamra (6); f. Natrun (2). Data from: Galileo Solid State Imaging (SSI)/Voyager Imaging Science Subsystem (ISS).

Physical properties of Trans-Neptunian Objects (TNOs) have been of increasing interest in the last two decades, as these objects are considered to be among the least altered through the Solar System evolution, and thus preserve valuable information about its origin [1]. The study of these objects through the ground-based method of stellar occultations has risen in the last years, as this technique allows the determination of physical properties with considerably good accuracies [2,3,4]. Here we present the results of the multi-chord stellar occultation of the GAIA source 3444789965847631104 (mv≈16.8) by the TNO (19521) Chaos on 2020 November 20, which was predicted within our systematic programme on stellar occultations by TNOs and outer solar system bodies [5]. The prediction was updated with astrometric observations carried out two days before the event with the 1.23-m telescope at Calar Alto observatory in Almería, Spain, and it was favorable to the South of Europe. The campaign that we organized involved 19 observing sites and resulted in three positive detections, one of them obtained from the 4.2-m WHT telescope at La Palma, 11 negative detections, and 5 sites that could not observe due to bad weather. We derived the instantaneous limb of Chaos by fitting the extremities of the positive chords to an ellipse to determine accurate size, shape, and geometric albedo for this object. The preliminary results give a slightly smaller area-equivalent diameter than the one derived from Herschel thermal data [6], but photometric observations of this object are still under analysis to complement and improve the results. References[1] Morbidelli, A., Levison, H. F., & Gomes, R. 2008, ed. M. A. Barucci, H. Boehnhardt, D. P. Cruikshank, A. Morbidelli, R. Dotson, 275[2] Ortiz, J. L., Sicardy, B., Braga-Ribas, F., et al. 2012, Nature, 491, 566[3] Braga-Ribas, F., Sicardy, B., Ortiz, J. L., et al. 2013, ApJ, 773, 26[4] Ortiz, J.L., Santos-Sanz, P., Sicardy, B., et al. 2017, Nature, 550, 7675, pp. 219-223[5] Camargo, J. I. B., Vieira-Martins, R., Assafin, M., et al. 2014, A&A, 561, A37[6] Vilenius, E., Kiss, C., Mommert, M., Müller, T., et al. 2012, A&A, 541, A94 Acknowledgements We acknowledge financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). Part of the research leading to these results has received funding from the European Research Council under the European Community’s H2020 (2014-2020/ERC Grant Agreement no. 669416 “LUCKY STAR”). M.V-L. acknowledges funding from Spanish project AYA2017-89637-R (FEDER/MICINN). P.S-S. acknowledges financial support by the Spanish grant AYA-RTI2018-098657-J-I00 ``LEO-SBNAF'' (MCIU/AEI/FEDER, UE). This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). We are grateful to the CAHA and OSN staffs. This research is partially based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by Junta de Andalucía and Consejo Superior de Investigaciones Científicas (IAA-CSIC). This research was also partially based on observation carried out at the Observatorio de Sierra Nevada (OSN) operated by Instituto de Astrofísica de Andalucía (CSIC). Partially based on observations made with the Tx40 telescope at the Observatorio Astrofísico de Javalambre in Teruel, a Spanish Infraestructura Cientifico-Técnica Singular (ICTS) owned, managed and operated by the Centro de Estudios de Física del Cosmos de Aragón (CEFCA). Tx40 is funded with the Fondos de Inversiones de Teruel (FITE).