scholarly journals Masses of asteroids and total mass of the main asteroid belt

2015 ◽  
Vol 10 (S318) ◽  
pp. 212-217
Author(s):  
E. V. Pitjeva ◽  
N. P. Pitjev
Keyword(s):  
Total Mass ◽  
Radar Data ◽  
Asteroid Belt ◽  
Two Dimensional ◽  
Binary Asteroids ◽  
One Dimensional ◽  
Main Asteroid Belt ◽  
The Individual ◽  
The Masses ◽  
Academy Of Sciences

AbstractAn estimation of the mass of the main asteroid belt was made on the basis of the new version of EPM2014 ephemerides of the Institute of Applied Astronomy of Russian Academy of Sciences using about 800000 positional observations of planets and spacecraft. We obtained the individual estimations of masses of large asteroids from radar data, as well as estimates of the masses of asteroids by using known diameters and estimated average densities for the three taxonomic types (C, S, M), and used the known mass values of binary asteroids and asteroids to which spacecraft approached. A two-dimensional homogeneous annulus with dimensions corresponding observed width of the main asteroid belt (2.06 au and 3.27 au) was used instead of a previous massive one-dimensional ring for modeling total perturbations from small asteroids. The obtained value of the total mass of the main asteroid belt is (12.25 ± 0.19)10−10M⊙.

2-D AUTOMATIC COMPOSITION OF NODAL VALUES FROM NUMERICAL MODEL USING SCRIPT PROGRAMMING

2013 ◽  
Vol 62 (1) ◽  
Author(s):  
Rudi Heriansyah
Keyword(s):  
Finite Element ◽  
Numerical Modeling ◽  
Numerical Model ◽  
Finite Difference ◽  
Two Dimensional ◽  
Commercial Software ◽  
One Dimensional ◽  
Automatic Composition ◽  
The Individual ◽  
Individual Nodes

There are many commercial software to perform numerical modeling based on finite element (FEM) and finite difference (FDM) methods. It is often a requirement to the designer, that the values of the individual nodes in the numerical model are known. Usually, these softwares provide two methods to achieve this; firstly, by clicking directly onto the nodes of interest and secondly, by saving or exporting the whole nodal values to an external file. The former way is appropriate for models with small number of nodes, but as the number of nodes increases, it is no longer an efficient or effective way. Through the latter method, all nodal values are obtained, however the values are one-dimensional, and in some cases, only certain nodal values are required for presentation. In this paper, an algorithm for automatic composition of nodal values obtained from the second method mentioned above. The composed nodal values will be in two-dimensional form as this is the format used for uniform shaped model (square or rectangular). Since numerical softwares usually have facilities to save the data in a spreadsheet format, the proposed algorithm is implemented in this environment by using spreadsheet script programming.

scholarly journals GJ 273: on the formation, dynamical evolution, and habitability of a planetary system hosted by an M dwarf at 3.75 parsec

2020 ◽  
Vol 641 ◽  
pp. A23 ◽  
Author(s):  
Francisco J. Pozuelos ◽  
Juan C. Suárez ◽  
Gonzalo C. de Elía ◽  
Zaira M. Berdiñas ◽  
Andrea Bonfanti ◽  
...  
Keyword(s):  
Planetary System ◽  
Kuiper Belt ◽  
Dynamical Evolution ◽  
Asteroid Belt ◽  
Physical Parameters ◽  
Planetary Formation ◽  
Low Mass Stars ◽  
The Individual ◽  
The Masses ◽  
M Dwarf

Context. Planets orbiting low-mass stars such as M dwarfs are now considered a cornerstone in the search for planets with the potential to harbour life. GJ 273 is a planetary system orbiting an M dwarf only 3.75 pc away, which is composed of two confirmed planets, GJ 273b and GJ 273c, and two promising candidates, GJ 273d and GJ 273e. Planet GJ 273b resides in the habitable zone. Currently, due to a lack of observed planetary transits, only the minimum masses of the planets are known: Mb sin ib = 2.89 M⊕, Mc sin ic = 1.18 M⊕, Md sin id = 10.80 M⊕, and Me sin ie = 9.30 M⊕. Despite its interesting character, the GJ 273 planetary system has been poorly studied thus far. Aims. We aim to precisely determine the physical parameters of the individual planets, in particular, to break the mass–inclination degeneracy to accurately determine the mass of the planets. Moreover, we present a thorough characterisation of planet GJ 273b in terms of its potential habitability. Methods. First, we explored the planetary formation and hydration phases of GJ 273 during the first 100 Myr. Secondly, we analysed the stability of the system by considering both the two- and four-planet configurations. We then performed a comparative analysis between GJ 273 and the Solar System and we searched for regions in GJ 273 which may harbour minor bodies in stable orbits, that is, the main asteroid belt and Kuiper belt analogues. Results. From our set of dynamical studies, we find that the four-planet configuration of the system allows us to break the mass–inclination degeneracy. From our modelling results, the masses of the planets are unveiled as: 2.89 ≤ Mb ≤ 3.03 M⊕, 1.18 ≤ Mc ≤ 1.24 M⊕, 10.80 ≤ Md ≤ 11.35 M⊕, and 9.30 ≤ Me ≤ 9.70 M⊕. These results point to a system that is likely to be composed of an Earth-mass planet, a super-Earth and two mini-Neptunes. Based on planetary formation models, we determine that GJ 273b is likely an efficient water captor while GJ 273c is probably a dry planet. We find that the system may have several stable regions where minor bodies might reside. Collectively, these results are used to offer a comprehensive discussion about the habitability of GJ 273b.

Polynuclear chloromercurate(II) systems in their chloropyridinium salts

1999 ◽  
Vol 55 (3) ◽  
pp. 396-409 ◽  
Author(s):  
Anthony Linden ◽  
Bruce D. James ◽  
John Liesegang ◽  
Nick Gonis
Keyword(s):  
Hydrogen Bonds ◽  
Two Dimensional ◽  
Cross Link ◽  
One Dimensional ◽  
Dimensional Network ◽  
The Individual ◽  
Compound Ii

The chloromercurate(II) salts of 2-, 3- and 4-chloropyridine display a variety of anion stoichiometries and structures, including the rare [Hg3Cl10]4− stoichiometry. 2-Chloropyridinium trichloromercurate(II), (I), (C5H5ClN)[HgCl3], monoclinic, P21/n, a = 9.094 (8), b = 18.143 (4), c = 12.902 (3) Å, β = 106.13 (4)° with Z = 8, has the [HgCl3]− stoichiometry, but the anions are infinite chains composed of [HgCl3]−, HgCl2 and Cl− moieties linked by longer Hg...Cl contacts. Hydrogen bonds link the cations to the formal Cl− ions. Tetrakis(3-chloropyridinium) decachlorotrimercurate(II), (II), (C5H5ClN)4[Hg3Cl10], monoclinic, P21/n, a = 7.522 (2), b = 28.046 (3), c = 9.165 (2) Å, β = 105.78 (2)° with Z = 2, has the rare [Hg3Cl10]4− stoichiometry and contains infinite one-dimensional double-stranded {([HgCl4]2−)2 [HgCl2]} n anionic chains made up of linear HgCl2 and distorted [HgCl4]2− entities linked together by longer Hg...Cl contacts. The HgCl2 moieties are joined by double [HgCl4]2− bridges. Hydrogen bonds link the cations to the sides of the anionic columns. Tetrakis(4-chloropyridinium) decachlorotrimercurate(II), (III), (C5H5ClN)4[Hg3Cl10], triclinic, P1¯, a = 9.907 (3), b = 13.226 (2), c = 7.282 (2) Å, α = 84.41 (2), β = 74.81 (2), γ = 87.34 (2)° with Z = 1, also has the [Hg3Cl10]4− stoichiometry and the same type of {([HgCl4]2−)2[HgCl2]} n anionic chains that were found in compound (II), but the formal HgCl2 and [HgCl4]2− moieties are more discrete with much weaker contacts linking the individual units. Bifurcated hydrogen bonds with the cations cross-link the anionic chains to form an infinite two-dimensional network. Second forms of the 3- and 4-chloropyridinium salts were also obtained. 3-Chloropyridinium trichloromercurate(II), (IV), (C5H5ClN)[HgCl3], monoclinic, P21/c, a = 7.243 (5), b = 22.145 (8), c = 12.320 (3) Å, β = 99.52 (3)° with Z = 8, has the [HgCl3]− stoichiometry, but the anions are infinite chains composed of distorted [Hg2Cl6]2− moieties. Bifurcated hydrogen bonds from the cations cross-link the anionic chains to form infinite two-dimensional layers. Bis(4-chloropyridinium) hexachlorodimercurate(II), (V), (C5H5ClN)2[Hg2Cl6], monoclinic, C2/m, a = 13.447 (3), b = 7.534 (2), c = 9.939 (2) Å, β = 97.48 (2)° with Z = 2, contains highly symmetrical discrete [Hg2Cl6]2−anions. Bifurcated hydrogen bonds from the cations interconnect the anions to form infinite one-dimensional chains.

scholarly journals DEVELOPMENT OF PERSONALITY AMBIVALENCE OF YOUNG PEOPLE IN THE CONTEXT OF PERSONAL INTEGRATIVE CONCEPT

2016 ◽  
Author(s):  
T. Zelinska
Keyword(s):  
Integrative Approach ◽  
Two Dimensional ◽  
Simultaneous Operation ◽  
Basic Principles ◽  
One Dimensional ◽  
Western Psychology ◽  
Phenomenological Studies ◽  
Integrative Concept ◽  
The Individual ◽  
Moderate Resistance

Author presented personal integrative concept, its basic principles, scientific terms, and the structural and dynamic model of ambivalence identity in adolescence. Revealed personal methodology that includes issues of consciousness, consciousness of ambivalence. Displayed the principles of humanistic and cognitive areas of Western psychology. It is shown that an integrative approach makes it possible to combine the heritage of academic and practical psychology, phenomenological studies of ambivalence personality. Ability to simultaneously coordinate the individual weak, moderate resistance opposites ambivalence of self-creation experience wholeness and harmony (with actual, and potential positive, negative) are growing in adolescence. Powerful resistance ambivalence consistently updates the alternation of opposites, which blocks semantic integrity and harmony of the individual. The relationships of positive and negative are caused by their value to the individual, so these opposites are coordinated and uncoordinated simultaneously or alternate. Presented components of personality ambivalence form a quality hierarchy levels: harmonious low - simultaneous operation of two-dimensional positive and negative; uncoordinated average - two-dimensional fluctuations and simultaneous operation of both positive and negative; disharmonious high - and consistent one-dimensional alternating positive and negative. In the article, the idea that the ambivalence of the individual in adolescence is growing awareness of the ability to balance, harmonize, react and globally integrate its opposite side support in the components. As a result, the individual simulates harmonization of ambivalence of global I.

scholarly journals Enrichment of the HR 8799 planets by minor bodies and dust

2020 ◽  
Vol 638 ◽  
pp. A50
Author(s):  
K. Frantseva ◽  
M. Mueller ◽  
P. Pokorný ◽  
F. F. S. van der Tak ◽  
I. L. ten Kate
Keyword(s):  
Total Mass ◽  
Kuiper Belt ◽  
Giant Planets ◽  
Asteroid Belt ◽  
Dynamical Structure ◽  
Mean Motion Resonances ◽  
Exoplanetary Systems ◽  
Test Particles ◽  
Main Asteroid Belt ◽  
The Impact

Context. In the Solar System, minor bodies and dust deliver various materials to planetary surfaces. Several exoplanetary systems are known to host inner and outer belts, analogues of the main asteroid belt and the Kuiper belt, respectively. Aims. We study the possibility that exominor bodies and exodust deliver volatiles and refractories to the exoplanets in the well-characterised system HR 8799. Methods. We performed N-body simulations to study the impact rates of minor bodies in the system HR 8799. The model consists of the host star, four giant planets (HR 8799 e, d, c, and b), 650 000 test particles representing the inner belt, and 1 450 000 test particles representing the outer belt. Moreover we modelled dust populations that originate from both belts. Results. Within a million years, the two belts evolve towards the expected dynamical structure (also derived in other works), where mean-motion resonances with the planets carve the analogues of Kirkwood gaps. We find that, after this point, the planets suffer impacts by objects from the inner and outer belt at rates that are essentially constant with time, while dust populations do not contribute significantly to the delivery process. We convert the impact rates to volatile and refractory delivery rates using our best estimates of the total mass contained in the belts and their volatile and refractory content. Over their lifetime, the four giant planets receive between 10−4 and 10−3 M⊕ of material from both belts. Conclusions. The total amount of delivered volatiles and refractories, 5 × 10−3 M⊕, is small compared to the total mass of the planets, 11 × 103 M⊕. However, if the planets were formed to be volatile-rich, their exogenous enrichment in refractory material may well be significant and observable, for example with JWST-MIRI. If terrestrial planets exist within the snow line of the system, volatile delivery would be an important astrobiological mechanism and may be observable as atmospheric trace gases.

scholarly journals 51. Interpretation of solar radio-frequency disk brightness distributions derived from observations with aerials extended in one dimension

1957 ◽  
Vol 4 ◽  
pp. 290-293 ◽  
Author(s):  
S. F. Smerd ◽  
J. P. Wild
Keyword(s):  
Solar Radio ◽  
Synthesis Method ◽  
One Dimension ◽  
Solar Model ◽  
Two Dimensional ◽  
Fourier Synthesis ◽  
One Dimensional ◽  
Finite Resolution ◽  
Dimensional Distribution ◽  
The Individual

Several recent papers have dealt with observations of brightness distributions over the solar disk, which were derived either from two-aerial interferometer observations at various spacings and orientations (e.g. O'Brien, 1953) [1], or from multiple-element interferometer fan-beam observations at various orientations (e.g. Christiansen and Warburton, 1954) [2], In each a two-dimensional distribution is derived from a number of essentially one-dimensional observations by a Fourier synthesis method described by O'Brien. The detail given by these methods must be limited by the finite resolution of the individual observations (limited by the maximum aperture of the aerial system), but the form of the limitation is not obvious, though its knowledge is required when relating the observations to a solar model.

scholarly journals Enrichment of the HR 8799 planets by minor bodies and dust

2020 ◽  
Author(s):  
Kateryna Frantseva ◽  
Michael Mueller ◽  
Petr Pokorný ◽  
Floris F. S. van der Tak ◽  
Inge Loes ten Kate
Keyword(s):  
Solar System ◽  
Total Mass ◽  
Kuiper Belt ◽  
Giant Planets ◽  
Asteroid Belt ◽  
Refractory Materials ◽  
Exoplanetary Systems ◽  
Main Asteroid Belt ◽  
The Impact ◽  
Shed Light

<p>Are minor bodies and dust delivering volatile and/or refractory materials in exoplanetary systems?<span class="Apple-converted-space"> </span></p> <p>Around ~20% of the nearest stars are found to host analogues of the main asteroid belt and the Kuiper belt. Our aim is to study the possibility of material delivery through minor bodies and dust to the planetary surfaces. To shed light on these delivery processes we extrapolate our Solar System scenarios to the exoplanetary system HR 8799. The system is known to host four giant planets and two belts of minor bodies.</p> <p>We performed a set of N-body simulations to study the impact rates of minor bodies and dust on the HR 8799 planets. We find that the planets suffer impacts by objects from the inner and outer belt. We convert these to volatile and refractory delivery rates using our best estimates of the total mass contained in the belts and their volatile/refractory content. Over their lifetime, the four giant planets receive between 10<sup>-4</sup> and 10<sup>-3 </sup>M<sub>Earth</sub> of material from both belts. This delivery leads to volatile and refractory enrichment of the planets that may be observable. Since the four giants HR 8799 e, d, c, b are located beyond the snow line (and presumably formed there), we expect them to be born volatile-rich. Therefore any future detection of refractories might imply delivery through impacts.</p>

A one-dimensional self-gravitating stellar gas

1966 ◽  
Vol 25 ◽  
pp. 46-48 ◽  
Author(s):  
M. Lecar
Keyword(s):  
Gravitational Field ◽  
Phase Space ◽  
Motion Picture ◽  
Space Distribution ◽  
Two Dimensional ◽  
One Dimensional ◽  
Phase Space Distribution ◽  
Dimensional Phase Space ◽  
The Mean

“Dynamical mixing”, i.e. relaxation of a stellar phase space distribution through interaction with the mean gravitational field, is numerically investigated for a one-dimensional self-gravitating stellar gas. Qualitative results are presented in the form of a motion picture of the flow of phase points (representing homogeneous slabs of stars) in two-dimensional phase space.

Perceived Mutual Understanding (PMU)

2019 ◽  
Vol 35 (1) ◽  
pp. 98-108 ◽  
Author(s):  
Michael J. Burtscher ◽  
Jeannette Oostlander
Keyword(s):  
Mutual Understanding ◽  
Team Cognition ◽  
Internal Reliability ◽  
Confirmatory Factor Analyses ◽  
Team Processes ◽  
One Dimensional ◽  
Item Parameters ◽  
Three Samples ◽  
Confirmatory Factor ◽  
The Individual

Abstract. Team cognition plays an important role in predicting team processes and outcomes. Thus far, research has focused on structured cognition while paying little attention to perceptual cognition. The lack of research on perceptual team cognition can be attributed to the absence of an appropriate measure. To address this gap, we introduce the construct of perceived mutual understanding (PMU) as a type of perceptual team cognition and describe the development of a respective measure – the PMU-scale. Based on three samples from different team settings ( NTotal = 566), our findings show that the scale has good psychometric properties – both at the individual as well as at the team-level. Item parameters were improved during a multistage process. Exploratory as well as confirmatory factor analyses indicate that PMU is a one-dimensional construct. The scale demonstrates sufficient internal reliability. Correlational analyses provide initial proof of construct validity. Finally, common indicators for inter-rater reliability and inter-rater agreement suggest that treating PMU as a team-level construct is justified. The PMU-scale represents a convenient and versatile measure that will potentially foster empirical research on perceptual team cognition and thereby contribute to the advancement of team cognition research in general.

Sign in / Sign up

Export Citation Format

Share Document