arXiv subjects

C. de la Fuente Marcos

Publications and source records attributed to C. de la Fuente Marcos.

At least 55 records · Page 3Linked to original sources

arXiv2018

LP 543-25: a rare low-mass runaway disk star

LP 543-25 or PSS 544-7 is a high proper-motion star located 458 pc from the Sun in the constellation of Canis Minor; it has been argued that it could be a candidate cannonball star ejected by a star cluster. Here, we revisit the issue of the kinematics of this interesting star using Gaia DR2. The heliocentric Galactic velocity components are (U, V, W) = (206, -289, 30) km/s; the corresponding Galactocentric Galactic velocity components show that LP 543-25 is moving in the Galactic plane and away from the Galactic Center at a rate of nearly 200 km/s, which is compatible with an origin in one of the multiple star clusters that inhabit the inner regions of the Milky Way. LP 543-25 appears to be a member of an elusive class of stars, the low-mass runaway stars. It is perhaps one of the closest and less massive runaway stars identified so far.

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arXiv2018

An independent confirmation of the future flyby of Gliese 710 to the solar system using Gaia DR2

Gliese 710 is a K7V star located 19 pc from the Sun in the constellation of Serpens Cauda, which is headed straight for the solar system. Berski & Dybczynski (2016) used data from Gaia DR1 to show that this star will be 13366 AU from the Sun in 1.35 Myr from now. Here, we present an independent confirmation of this remarkable result using Gaia DR2. Our approach is first validated using as test case that of the closest known stellar flyby, by the binary WISE J072003.20-084651.2 or Scholz's star. Our results confirm, within errors, those in Berski & Dybczynski (2016), but suggest a somewhat closer, both in terms of distance and time, flyby of Gliese 710 to the solar system. Such an interaction might not significantly affect the region inside 40 au as the gravitational coupling among the known planets against external perturbation can absorb efficiently such a perturbation, but it may trigger a major comet shower that will affect the inner solar system.

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arXiv2018

Comet C/2017 K2 (PANSTARRS): dynamically old or new?

At discovery time, C/2017 K2 (PANSTARRS) was the second most distant inbound active comet ever observed. It has been argued that this object is in the process of crossing the inner Solar System for the first time, but other authors have concluded that it is dynamically old. We have performed full N-body simulations for 3 Myr into the past using the latest public orbit determination for this object and most of them, 67%, are consistent with a bound and dynamically old Oort cloud comet, but about 29% of the studied orbits are compatible with an interstellar origin. Our independent calculations strongly suggest that C/2017 K2 is not a dynamically new Oort cloud comet.

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arXiv2018

Where the Solar system meets the solar neighbourhood: patterns in the distribution of radiants of observed hyperbolic minor bodies

Observed hyperbolic minor bodies might have an interstellar origin, but they can be natives of the Solar system as well. Fly-bys with the known planets or the Sun may result in the hyperbolic ejection of an originally bound minor body; in addition, members of the Oort cloud could be forced to follow inbound hyperbolic paths as a result of secular perturbations induced by the Galactic disc or, less frequently, due to impulsive interactions with passing stars. These four processes must leave distinctive signatures in the distribution of radiants of observed hyperbolic objects, both in terms of coordinates and velocity. Here, we perform a systematic numerical exploration of the past orbital evolution of known hyperbolic minor bodies using a full N-body approach and statistical analyses to study their radiants. Our results confirm the theoretical expectations that strong anisotropies are present in the data. We also identify a statistically significant overdensity of high-speed radiants towards the constellation of Gemini that could be due to the closest and most recent known fly-by of a star to the Solar system, that of the so-called Scholz's star. In addition to and besides 1I/2017 U1 (`Oumuamua), we single out eight candidate interstellar comets based on their radiants' velocities.

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arXiv2017

Ghosts of Jupiter's past: is 2017 UV43 a relative of comet Shoemaker-Levy 9?

The present-day orbit of 2017 UV43 resembles the average one of the fragments of comet Shoemaker-Levy 9. Here, we present numerical evidence suggesting that 2017 UV43 might be related to Shoemaker-Levy 9. With our exploratory results we intend to encourage a search for precovery images of 2017 UV43 and perhaps even follow-up observations that may help in improving its poorly determined orbit so its true dynamical nature can be understood.

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arXiv2017

Dynamically correlated minor bodies in the outer Solar system

The organization of the orbits of most minor bodies in the Solar system seems to follow random patterns, the result of billions of years of chaotic dynamical evolution. Much as heterogeneous orbital behaviour is ubiquitous, dynamically coherent pairs and groups of objects are also present everywhere. Although first studied among the populations of asteroids and comets that inhabit or traverse the inner Solar system, where they are very numerous, at least one asteroid family has been confirmed to exist in the outer Solar system and two other candidates have been proposed in the literature. Here, we perform a systematic search for statistically significant pairs and groups of dynamically correlated objects through those with semimajor axis greater than 25 au, applying a novel technique that uses the angular separations of orbital poles and perihelia together with the differences in time of perihelion passage to single out pairs of relevant objects. Our analysis recovers well-known, dynamically coherent pairs and groups of comets and trans-Neptunian objects and uncovers a number of new ones, prime candidates for further spectroscopic study.

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arXiv2017

Dynamical evolution of near-Earth asteroid 1991 VG

The discovery of 1991 VG on 1991 November 6 attracted an unprecedented amount of attention as it was the first near-Earth object (NEO) ever found on an Earth-like orbit. At that time, it was considered by some as the first representative of a new dynamical class of asteroids, while others argued that an artificial (terrestrial or extraterrestrial) origin was more likely. Over a quarter of a century later, this peculiar NEO has been recently recovered and the new data may help in confirming or ruling out early theories about its origin. Here, we use the latest data to perform an independent assessment of its current dynamical status and short-term orbital evolution. Extensive N-body simulations show that its orbit is chaotic on time-scales longer than a few decades. We confirm that 1991 VG was briefly captured by Earth's gravity as a minimoon during its previous fly-by in 1991-1992; although it has been a recurrent transient co-orbital of the horseshoe type in the past and it will return as such in the future, it is not a present-day co-orbital companion of the Earth. A realistic NEO orbital model predicts that objects like 1991 VG must exist and, consistently, we have found three other NEOs --2001 GP2, 2008 UA202 and 2014 WA366-- which are dynamically similar to 1991 VG. All this evidence confirms that there is no compelling reason to believe that 1991 VG is not natural.

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arXiv2017

Transient Co-orbitals of Venus: An Update

Venus has no known satellites, but has four known co-orbitals: (322756) 2001 CK32, 2002 VE68, 2012 XE133, and 2013 ND15. Here, we present numerical evidence suggesting that 2015 WZ12 is a possible Venus co-orbital; it might have been until recently a transient Trojan. Follow-up observations of this target in the near future will be difficult, though.

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arXiv2017

Pole, Pericenter, and Nodes of the Interstellar Minor Body A/2017 U1

Here, we explore some peculiar orbital features of the recently discovered asteroid A/2017 U1, which is a clear outlier when considering the average value of the eccentricity of known hyperbolic comets. As for the orientation of its orbit in space, the orbital plane of A/2017 U1 seems to be away from any obvious clusters present for this population. The orbital nodes of A/2017 U1 are well away from the paths of the planets of the Solar System and the Sun. All these orbital properties appear to confirm A/2017 U1 as the first known interstellar asteroid.

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arXiv2017

Binary stripping as a plausible origin of correlated pairs of extreme trans-Neptunian objects

Asteroids that follow similar orbits may have a dynamical connection as their current paths could be the result of a past interaction with a massive perturber. The pair of extreme trans-Neptunian objects or ETNOs (474640) 2004 VN112-2013 RF98 exhibits peculiar relative orbital properties, including a difference in longitude of the ascending node of just 1.61 degrees and 3.99 degrees in inclination. In addition, their reflectance spectra are similar in the visible portion of the spectrum. The origin of these similarities remains unclear. Neglecting observational bias, viable scenarios that could explain this level of coincidence include fragmentation and binary dissociation. Here, we present results of extensive direct N-body simulations of close encounters between wide binary ETNOs and one trans-Plutonian planet. We find that wide binary ETNOs can dissociate during such interactions and the relative orbital properties of the resulting unbound couples match reasonably well those of several pairs of known ETNOs, including 474640-2013 RF98. The possible presence of former binaries among the known ETNOs has strong implications for the interpretation of the observed anisotropies in the distributions of the directions of their orbital poles and perihelia.

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arXiv2017

Asteroid 2017 FZ2 et al.: signs of recent mass-shedding from YORP?

The first direct detection of the asteroidal YORP effect, a phenomenon that changes the spin states of small bodies due to thermal reemission of sunlight from their surfaces, was obtained for (54509) YORP 2000 PH5. Such an alteration can slowly increase the rotation rate of asteroids, driving them to reach their fission limit and causing their disruption. This process can produce binaries and unbound asteroid pairs. Secondary fission opens the door to the eventual formation of transient but genetically-related groupings. Here, we show that the small near-Earth asteroid (NEA) 2017 FZ2 was a co-orbital of our planet of the quasi-satellite type prior to their close encounter on 2017 March 23. Because of this flyby with the Earth, 2017 FZ2 has become a non-resonant NEA. Our N-body simulations indicate that this object may have experienced quasi-satellite engagements with our planet in the past and it may return as a co-orbital in the future. We identify a number of NEAs that follow similar paths, the largest named being YORP, which is also an Earth's co-orbital. An apparent excess of NEAs moving in these peculiar orbits is studied within the framework of two orbit population models. A possibility that emerges from this analysis is that such an excess, if real, could be the result of mass shedding from YORP itself or a putative larger object that produced YORP. Future spectroscopic observations of 2017 FZ2 during its next visit in 2018 (and of related objects when feasible) may be able to confirm or reject this interpretation.

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arXiv2017

Evidence for a possible bimodal distribution of the nodal distances of the extreme trans-Neptunian objects: avoiding a trans-Plutonian planet or just plain bias?

It is a well-known fact that the presence of a massive perturber interacting with a population of minor bodies following very eccentric orbits can strongly affect the distribution of their nodal distances. The details of this process have been explored numerically and its outcome confirmed observationally in the case of Jupiter, where a bimodal distribution of nodal distances of comets has been found. Here, we show evidence for a possible bimodal distribution of the nodal distances of the extreme trans-Neptunian objects (ETNOs) in the form of a previously unnoticed correlation between nodal distance and orbital inclination. This proposed correlation is unlikely to be the result of observational bias as data for both large semimajor axis Centaurs and comets fit well into the pattern found for the ETNOs, and all these populations are subjected to similar background perturbations when moving well away from the influence of the giant planets. The correlation found is better understood if these objects tend to avoid a putative planet with semimajor axis in the range 300-400 au.

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arXiv2017

Asteroid 2014 YX49: a large transient Trojan of Uranus

In the outer Solar system, primordial Trojan asteroids may have remained dynamically stable for billions of years. Several thousands of them accompany Jupiter in its journey around the Sun and a similarly large population may be hosted by Neptune. In addition, recently captured or transient Jovian and Neptunian Trojans are not uncommon. In contrast, no Trojans of Saturn have been found yet and just one Uranian Trojan is known, 2011 QF99. Here, we discuss the identification of a second Trojan of Uranus: 2014 YX49. Like 2011 QF99, 2014 YX49 is a transient L4 Trojan although it orbits at higher inclination (25.55 degrees versus 10.83 degrees), is larger (absolute magnitude of 8.5 versus 9.7) and its libration period is slightly shorter (5.1 versus 5.9 kyr); contrary to 2011 QF99, its discovery was not the result of a targeted survey. It is less stable than 2011 QF99; our extensive N-body simulations show that 2014 YX49 may have been following a tadpole trajectory ahead of Uranus for about 60 kyr and it can continue doing so for another 80 kyr. Our analysis suggests that it may remain as co-orbital for nearly 1 Myr. As in the case of 2011 QF99, the long-term stability of 2014 YX49 is controlled by Jupiter and Neptune, but it is currently trapped in the 7:20 mean motion resonance with Saturn. Consistently, the dynamical mechanism leading to the capture into and the ejection from the Trojan state involves ephemeral multibody mean motion resonances.

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arXiv2017

Visible spectra of (474640) 2004 VN112-2013 RF98 with OSIRIS at the 10.4 m GTC: evidence for binary dissociation near aphelion among the extreme trans-Neptunian objects

The existence of significant anisotropies in the distributions of the directions of perihelia and orbital poles of the known extreme trans-Neptunian objects (ETNOs) has been used to claim that trans-Plutonian planets may exist. Among the known ETNOs, the pair (474640) 2004 VN112-2013 RF98 stands out. Their orbital poles and the directions of their perihelia and their velocities at perihelion/aphelion are separated by a few degrees, but orbital similarity does not necessarily imply common physical origin. In an attempt to unravel their physical nature, visible spectroscopy of both targets was obtained using the OSIRIS camera-spectrograph at the 10.4 m Gran Telescopio Canarias (GTC). From the spectral analysis, we find that 474640-2013 RF98 have similar spectral slopes (12 vs. 15 %/0.1um), very different from Sedna's but compatible with those of (148209) 2000 CR105 and 2012 VP113. These five ETNOs belong to the group of seven linked to the Planet Nine hypothesis. A dynamical pathway consistent with these findings is dissociation of a binary asteroid during a close encounter with a planet and we confirm its plausibility using N-body simulations. We thus conclude that both the dynamical and spectroscopic properties of 474640-2013 RF98 favour a genetic link and their current orbits suggest that the pair was kicked by a perturber near aphelion.

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arXiv2016

Homing in for New Year: impact parameters and pre-impact orbital evolution of meteoroid 2014 AA

On 2008 October 7, small asteroid 2008 TC3 turned itself into the parent body of the first meteor ever to be predicted before entering the Earth's atmosphere. Over five years later, the 2014 AA event became the second instance of such an occurrence. The uncertainties associated with the pre-impact orbit of 2008 TC3 are relatively small because thousands of observations were made during the hours preceding the actual meteor airburst. In sharp contrast, 2014 AA was only observed seven times before impact and consequently its trajectory is somewhat uncertain. Here, we present a recalculation of the impact parameters -location and timing- of this meteor based on infrasound recordings. The new values and their uncertainties together with Monte Carlo and N-body techniques, are applied to obtain an independent determination of the pre-impact orbit of 2014 AA. Our orbital solution is used to investigate the possible presence of known near-Earth objects (NEOs) moving in similar orbits. Prior to impact, 2014 AA was subjected to a web of overlapping secular resonances and it followed a path similar to those of 2011 GJ3, 2011 JV10, 2012 DJ54, and 2013 NJ4. NEOs in this transient group have their orbits controlled by close encounters with the Earth-Moon system at perihelion and Mars at aphelion, perhaps constituting a dynamical family. Extensive comparison with other studies is also presented.

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arXiv2016

Asteroid (469219) 2016 HO3, the smallest and closest Earth quasi-satellite

A number of Earth co-orbital asteroids experience repeated transitions between the quasi-satellite and horseshoe dynamical states. Asteroids 2001 GO2, 2002 AA29, 2003 YN107 and 2015 SO2 are well-documented cases of such a dynamical behaviour. These transitions depend on the gravitational influence of other planets, owing to the overlapping of a multiplicity of secular resonances. Here, we show that the recently discovered asteroid (469219) 2016 HO3 is a quasi-satellite of our planet -the fifth one, joining the ranks of (164207) 2004 GU9, (277810) 2006 FV35, 2013 LX28 and 2014 OL339. This new Earth co-orbital also switches repeatedly between the quasi-satellite and horseshoe configurations. Its current quasi-satellite episode started nearly 100 yr ago and it will end in about 300 yr from now. The orbital solution currently available for this object is very robust and our full N-body calculations show that it may be a long-term companion (time-scale of Myr) to our planet. Among the known Earth quasi-satellites, it is the closest to our planet and as such, a potentially accessible target for future in situ study. Due to its presumably lengthy dynamical relationship with the Earth and given the fact that at present and for many decades this transient object remains well positioned with respect to our planet, the results of spectroscopic studies of this small body, 26-115 m, may be particularly useful to improve our understanding of the origins -local or captured- of Earth's co-orbital asteroid population. The non-negligible effect of the uncertainty in the value of the mass of Jupiter on the stability of this type of co-orbitals is also briefly explored.

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arXiv2016

The analemma criterion: accidental quasi-satellites are indeed true quasi-satellites

In the Solar system, a quasi-satellite is an object that follows a heliocentric path with an orbital period that matches almost exactly with that of a host body (planetary or not). The trajectory is of such nature that, without being gravitationally attached, the value of the angular separation between host and quasi-satellite as seen from the Sun remains confined within relatively narrow limits for time-spans that exceed the length of the host's sidereal orbital period. Here, we show that under these conditions, a quasi-satellite traces an analemma in the sky as observed from the host in a manner similar to that found for geosynchronous orbits. The analemmatic curve (figure-eight-, teardrop-, ellipse-shaped) results from the interplay between the tilt of the rotational axis of the host and the properties of the orbit of the quasi-satellite. The analemma criterion can be applied to identify true quasi-satellite dynamical behaviour using observational or synthetic astrometry and it is tested for several well-documented quasi-satellites. For the particular case of 15810 (1994 JR1), a putative accidental quasi-satellite of dwarf planet Pluto, we show explicitly that this object describes a complex analemmatic curve for several Plutonian sidereal periods, confirming its transient quasi-satellite status.

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arXiv2016

Finding Planet Nine: apsidal anti-alignment Monte Carlo results

The distribution of the orbital elements of the known extreme trans-Neptunian objects or ETNOs has been found to be statistically incompatible with that of an unperturbed asteroid population following heliocentric or, better, barycentric orbits. Such trends, if confirmed by future discoveries of ETNOs, strongly suggest that one or more massive perturbers could be located well beyond Pluto. Within the trans-Plutonian planets paradigm, the Planet Nine hypothesis has received much attention as a robust scenario to explain the observed clustering in physical space of the perihelia of seven ETNOs which also exhibit clustering in orbital pole position. Here, we revisit the subject of clustering in perihelia and poles of the known ETNOs using barycentric orbits, and study the visibility of the latest incarnation of the orbit of Planet Nine applying Monte Carlo techniques and focusing on the effects of the apsidal anti-alignment constraint. We provide visibility maps indicating the most likely location of this putative planet if it is near aphelion. We also show that the available data suggest that at least two massive perturbers are present beyond Pluto.

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