scholarly journals Observational Completion Limit of Minor Planets from the Asteroid Belt to Jupiter Trojans

2020 ◽  
Vol 1 (3) ◽  
pp. 75
Author(s):  
Nathanial P. Hendler ◽  
Renu Malhotra
Keyword(s):  
Asteroid Belt ◽  
Minor Planets

scholarly journals Three-Dimensional Distributions of Minor Planets and Comets

1979 ◽  
Vol 81 ◽  
pp. 239-244
Author(s):  
Ľubor Kresák
Keyword(s):  
Three Dimensional ◽  
Asteroid Belt ◽  
Minor Planets ◽  
Orbital Elements ◽  
Meteor Streams ◽  
Stellar Astronomy ◽  
Kirkwood Gaps ◽  
The Individual ◽  
To Receive ◽  
Orbital Data

The attitude toward the systems of interplanetary objects is largely different from that accustomed in stellar astronomy. The stellar systems are viewed from the outside, with their shape, population, and internal structure apparent at first glance. The motions are difficult to recognize, if ever, and so the individual orbits are degraded to a background mechanism maintaining the observed organization and rotation of the system. In contrast to this, we dispose of copious information on the dynamics of individual interplanetary objects, but the bodies to which the orbital data refer are sampled under the influence of strong selection effects. Lacking a consistent survey of their systems, we tend to think of them in terms of the biased statistics in the phase-space of orbital elements, rather than in terms of the real three-dimensional distributions. No wonder that we often come across serious misrepresentations: the asteroid belt depicted as a plane ring divided by the Kirkwood gaps like the ring of Saturn; the Trojan clouds as small spherical systems resembling globular star clusters; or the meteor streams as elongated rings of uniform width and population all around. And we seem to receive these gross misrepresentations with surprisingly little annoyance.

Total asteroid mass from comet perturbations

1974 ◽  
Vol 22 ◽  
pp. 141
Author(s):  
T. C. van Flandern
Keyword(s):  
Total Mass ◽  
Large Mass ◽  
Asteroid Belt ◽  
Force Model ◽  
Minor Planets ◽  
Short Period ◽  
Out Of Plane ◽  
Halley's Comet ◽  
The Mean ◽  
Open Question

AbstractDeviations of Halley’s Comet from its predicted orbit more closely approximate perturbations caused by a gravitational ring of matter, rather than a point source or the usual nongravitational force model for comets. This is especially evident from the perturbations on the perihelion, node, and inclination for this comet. It is hypothesized that the gravitating ring was the asteroid belt. The observed deviations were used to solve for the total mass of the asteroids, giving the result of fifty times the mass of the Earth. Such a large mass can be ruled out by the absence of corresponding secular perturbations on the orbit of Mars, provided that the mean plane and shape of the asteroid belt do not correspond exactly with the orbit of Mars.A mean set of elements for the asteroid belt was determined by averaging the elements of the numbered minor planets, and three short-period comets were then tested with the same hypothesis. It is concluded that there is no correlations between perturbations due to the mean asteroid belt and those exhibited by the three short-period comets.The upper limit for the total mass of the asteroids, set by Mars, is 0.1 Earth mass. The source of the out-of-plane perturbations and of the cause of the secular increase in perihelion distance for Halley’s Comet is still an open question, since these cannot be explained by the usual nongravitational force model for comets.

On nearly-commensurable periods in the restricted problem of three bodies, with calculations of the long-period variations in the interior 2:1 case

1966 ◽  
Vol 25 ◽  
pp. 197-222 ◽  
Author(s):  
P. J. Message
Keyword(s):  
Periodic Solution ◽  
Periodic Solutions ◽  
Large Amplitude ◽  
Restricted Problem ◽  
Small Amplitude ◽  
Minor Planets ◽  
Long Period ◽  
Numerical Integrations ◽  
Period Variations ◽  
The Mean

An analytical discussion of that case of motion in the restricted problem, in which the mean motions of the infinitesimal, and smaller-massed, bodies about the larger one are nearly in the ratio of two small integers displays the existence of a series of periodic solutions which, for commensurabilities of the typep+ 1:p, includes solutions of Poincaré'sdeuxième sortewhen the commensurability is very close, and of thepremière sortewhen it is less close. A linear treatment of the long-period variations of the elements, valid for motions in which the elements remain close to a particular periodic solution of this type, shows the continuity of near-commensurable motion with other motion, and some of the properties of long-period librations of small amplitude.To extend the investigation to other types of motion near commensurability, numerical integrations of the equations for the long-period variations of the elements were carried out for the 2:1 interior case (of which the planet 108 “Hecuba” is an example) to survey those motions in which the eccentricity takes values less than 0·1. An investigation of the effect of the large amplitude perturbations near commensurability on a distribution of minor planets, which is originally uniform over mean motion, shows a “draining off” effect from the vicinity of exact commensurability of a magnitude large enough to account for the observed gap in the distribution at the 2:1 commensurability.

Brief summary of Kleť photographic search programme for minor planets

1999 ◽  
Vol 173 ◽  
pp. 189-192
Author(s):  
J. Tichá ◽  
M. Tichý ◽  
Z. Moravec
Keyword(s):  
Ccd Camera ◽  
Minor Planet ◽  
Minor Planets ◽  
Main Belt

AbstractA long-term photographic search programme for minor planets was begun at the Kleť Observatory at the end of seventies using a 0.63-m Maksutov telescope, but with insufficient respect for long-arc follow-up astrometry. More than two thousand provisional designations were given to new Kleť discoveries. Since 1993 targeted follow-up astrometry of Kleť candidates has been performed with a 0.57-m reflector equipped with a CCD camera, and reliable orbits for many previous Kleť discoveries have been determined. The photographic programme results in more than 350 numbered minor planets credited to Kleť, one of the world's most prolific discovery sites. Nearly 50 per cent of them were numbered as a consequence of CCD follow-up observations since 1994.This brief summary describes the results of this Kleť photographic minor planet survey between 1977 and 1996. The majority of the Kleť photographic discoveries are main belt asteroids, but two Amor type asteroids and one Trojan have been found.

The O–C diagrams of minor planets − a new approach to modelling the rotation

1999 ◽  
Vol 173 ◽  
pp. 185-188
Author(s):  
Gy. Szabó ◽  
K. Sárneczky ◽  
L.L. Kiss
Keyword(s):  
Error Analysis ◽  
Time Dependence ◽  
Theoretical Work ◽  
Minor Planet ◽  
Minor Planets ◽  
New Approach ◽  
Preliminary Results ◽  
Ccd Observations

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.

Comments on collision mechanics in ring systems

1984 ◽  
Vol 75 ◽  
pp. 407-422
Author(s):  
William K. Hartmann
Keyword(s):  
Asteroid Belt ◽  
Surface Erosion ◽  
Surface Layers ◽  
Ring Systems ◽  
Eclipse Observations ◽  
Saturn’S Rings ◽  
Saturn's Rings

ABSTRACTThe nature of collisions within ring systems is reviewed with emphasis on Saturn's rings. The particles may have coherent icy cores and less coherent granular or frosty surface layers, consistent with thermal eclipse observations. Present-day collisions of such ring particles do not cause catastrophic fragmentation of the particles, although some minor surface erosion and reaccretion is possible. Evolution by collisional fragmentation is thus not as important as in the asteroid belt.

scholarly journals Improving the dynamical reference frame through minor planet orbit correction using crossing point observations

1988 ◽  
Vol 128 ◽  
pp. 55-60
Author(s):  
Arthur L. Whipple ◽  
Raynor L. Duncombe ◽  
Paul D. Hemenway
Keyword(s):  
Computer Program ◽  
Reference Frame ◽  
Reference System ◽  
Hubble Space Telescope ◽  
Simulated Data ◽  
Minor Planet ◽  
Minor Planets ◽  
Space Telescope ◽  
Orbit Correction ◽  
Crossing Point

We have begun a program to establish a dynamical reference frame based on the motions of minor planets. The program will utilize observations from the Hubble Space Telescope, and will ultimately tie the HIPPARCOS reference system to a dynamical base. Thirty-four minor planets, 20 of which are suitable for observation with the Hubble Space Telescope, have been selected. Ground based observations, particularly crossing-point observations with long focus reflectors, have been initiated.A computer program to simultaneously solve for the corrections of the orbits of the 34 minor planets including the crossing-point observations, was successfully run. The observations are treated by the method of W. H. Jeffreys. Using simulated data, solutions with and without crossing point observations demonstrate the value of those observations to produce a homogeneous and coherent set of results.

scholarly journals Organic matter and water from asteroid Itokawa

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Q. H. S. Chan ◽  
A. Stephant ◽  
I. A. Franchi ◽  
X. Zhao ◽  
R. Brunetto ◽  
...  
Keyword(s):  
Organic Matter ◽  
Solar System ◽  
Parent Body ◽  
Asteroid Belt ◽  
True Nature ◽  
Water Ice ◽  
Nanocrystalline Graphite ◽  
Terrestrial Water ◽  
Solar System Bodies ◽  
Small Dust

AbstractUnderstanding the true nature of extra-terrestrial water and organic matter that were present at the birth of our solar system, and their subsequent evolution, necessitates the study of pristine astromaterials. In this study, we have studied both the water and organic contents from a dust particle recovered from the surface of near-Earth asteroid 25143 Itokawa by the Hayabusa mission, which was the first mission that brought pristine asteroidal materials to Earth’s astromaterial collection. The organic matter is presented as both nanocrystalline graphite and disordered polyaromatic carbon with high D/H and 15N/14N ratios (δD =  + 4868 ± 2288‰; δ15N =  + 344 ± 20‰) signifying an explicit extra-terrestrial origin. The contrasting organic feature (graphitic and disordered) substantiates the rubble-pile asteroid model of Itokawa, and offers support for material mixing in the asteroid belt that occurred in scales from small dust infall to catastrophic impacts of large asteroidal parent bodies. Our analysis of Itokawa water indicates that the asteroid has incorporated D-poor water ice at the abundance on par with inner solar system bodies. The asteroid was metamorphosed and dehydrated on the formerly large asteroid, and was subsequently evolved via late-stage hydration, modified by D-enriched exogenous organics and water derived from a carbonaceous parent body.

scholarly journals A thermophysical and dynamical study of the Hildas (1162) Larissa and (1911) Schubart

2021 ◽  
Author(s):  
Cristian F Chavez ◽  
T G Müller ◽  
J P Marshall ◽  
J Horner ◽  
H Drass ◽  
...  
Keyword(s):  
Thermal Inertia ◽  
Infrared Camera ◽  
Asteroid Belt ◽  
Effective Diameter ◽  
Early Solar System ◽  
Dynamical Study ◽  
Axis Ratio ◽  
Ellipsoidal Shape ◽  
Dynamical Simulations ◽  
Taxonomical Classification

Abstract The Hilda asteroids are among the least studied populations in the asteroid belt, despite their potential importance as markers of Jupiter’s migration in the early Solar system. We present new mid-infrared observations of two notable Hildas, (1162) Larissa and (1911) Schubart, obtained using the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST), and use these to characterise their thermal inertia and physical properties. For (1162) Larissa, we obtain an effective diameter of 46.5$^{+2.3}_{-1.7}$ km, an albedo of 0.12 ± 0.02, and a thermal inertia of 15$^{+10}_{-8}$ Jm−2s1/2K−1. In addition, our Larissa thermal measurements are well matched with an ellipsoidal shape with an axis ratio a/b=1.2 for the most-likely spin properties. Our modelling of (1911) Schubart is not as refined, but the thermal data point towards a high-obliquity spin-pole, with a best-fit a/b=1.3 ellipsoidal shape. This spin-shape solution is yielding a diameter of 72$^{+3}_{-4}$ km, an albedo of 0.039± 0.02, and a thermal inertia below 30 Jm−2s1/2K−1 (or 10$^{+20}_{-5}$ Jm−2s1/2K−1). As with (1162) Larissa, our results suggest that (1911) Schubart is aspherical, and likely elongated in shape. Detailed dynamical simulations of the two Hildas reveal that both exhibit strong dynamical stability, behaviour that suggests that they are primordial, rather than captured objects. The differences in their albedos, along with their divergent taxonomical classification, suggests that despite their common origin, the two have experienced markedly different histories.

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