Wyniki wyszukiwania - BazTech

1

System of Long-Period Comets as Indicator of the Large Planetary Body on the Periphery of the Solar System

Guliyev A. S., Guliyev R. A.

Acta Astronomica

|

2019

|

Vol. 69, No. 2

177--203

EN

We study some particular aspects of the hypothesis about the existence of a highly inclined massive celestial body at a distance of 250-400 au. The analysis covers 1249 long-period comets (LPCs) observed up to 2017, having q and Q greater than 0.1 au and 30 au respectively. A plane or planes around which the concentration of perihelia occurs have been searched. The search for such planes has been carried out for groups of LPCs, separated by clusters in T (discovery date), e, q, H (absolute magnitude), Q, 1/aori ("original" a), etc. In almost all cases two types of planes or zones have been detected: the first one is very close to the ecliptic, the other one has the parameters: ip=86°, Ωp=271°. According to the tested hypothesis there is a massive perturber at a distance of 250-400 au from the Sun. We show that the number of aphelia and distant nodes of long-period comet orbits within this interval (250-400 au) significantly exceeds the expected value. The distributions of Q and distant comet nodes may signal the presence of a massive perturber near 300 au. We have estimated that the most probable orbital elements of the hypothetical planet are a=339±34 au, e=0.16±0.02, ω=57°±15°, Ω=272.°7±3°, i=86°±2°. To test the stability of such an orbit as well as its influence on other planets, a model of solar system that includes only the Jovian planets and the putative perturber was integrated for 1 billion years, assuming that the mass of the highly inclined perturber is about 10 Earth masses.

2

The expansion of the inverse of the mutual distance between two planets raised to any real integer using Taylor theorem and elliptic expansions Part I, Theoretical results

Elmabsout B., Kamel O. M., Soliman A. S.

Mechanics and Mechanical Engineering

|

2018

|

Vol. 22, nr 4

1175--1195

EN

We introduce in this part the method to obtain the literal expansion of the mutual distance between two planets of the solar system raised to any negative real integer.

3

A second order secular J-S planetary theory. Part I, Lemma

Kamel O. M., Soliman A. S.

Mechanics and Mechanical Engineering

|

2018

|

Vol. 22, nr 4

871--874

EN

A concise lemma is given for the construction of a semi-analytic Hamiltonian second order secular J-S planetary theory using the Jacobi-Radau system of origins and in terms of the non-singular variables of H. Poincaré. We truncate our expansions at the desired power in the eccentricities and the sines of the inclinations.

4

A First Order Jupiter Saturn Planetary Theory. Numerical Results

Kamel O. M., Soliman A. S., El Mabsout B.

Mechanics and Mechanical Engineering

|

2016

|

Vol. 20, nr 1

59--73

EN

We present the numerical analysis solution of the eight ordinary non linear differential equations of a first order secular J – S planetary theory. There is no general solution for these equations. We deal with the Poincare’ variables Hu, Ku, Pu, Qu; u=1,2 only. The solution is approximative, since we confine our treatment to a first order secular theory and truncate the Poisson series expansions at the fourth power in eccentricity – inclination.

5

Fast Geometric Method for Calculating Accurate Minimum Orbit Intersection Distances

Wiśniowski T., Rickman H.

Acta Astronomica

|

2013

|

Vol. 63, No. 2

293--307

EN

We present a new method to compute Minimum Orbit Intersection Distances (MOIDs) for arbitrary pairs of heliocentric orbits and compare it with Giovanni Gronchi's algebraic method. Our procedure is numerical and iterative, and the MOID configuration is found by geometric scanning and tuning. A basic element is the meridional plane, used for initial scanning, which contains one of the objects and is perpendicular to the orbital plane of the other. Our method also relies on an efficient tuning technique in order to zoom in on the MOID configuration, starting from the first approximation found by scanning. We work with high accuracy and take special care to avoid the risk of missing the MOID, which is inherent to our type of approach. We demonstrate that our method is both fast, reliable and flexible. It is freely available and its source Fortran code downloadable via our web page.

6

Behavior of Jupiter Non-Trojan Co-Orbitals

Wajer P., Królikowska M.

Acta Astronomica

|

2012

|

Vol. 62, No. 1

113--131

EN

Searching for the non-Trojan Jupiter co-orbitals we have numerically integrated orbits of 3160 asteroids and 24 comets discovered by October 2010 and situated within and close to the planet co-orbital region. Using this sample we have been able to select eight asteroids and three comets and analyze their orbital behavior in a great detail. Among them we have identified five new Jupiter co-orbitals: (241944) 2002 CU147, 2006 S.A.387, 2006 QL39, 2007 GH6, and 200P/Larsen, as well as we have analyzed six previously identified co-orbitals: (118624) 2000 HR24, 2006 UG185, 2001 QQ199, 2004 AE9, P/2003 WC7 LINEAR-CATALINA and P/2002 AR2 LINEAR. (241944) 2002 CU147 is currently on a quasi-satellite orbit with repeatable transitions into the tadpole state. Similar behavior shows 2007 GH6 which additionally librates in a compound tadpole-quasi-satellite orbit. 2006 QL39 and 2000P/Larsen are the co-orbitals of Jupiter which are temporarily moving in a horseshoe orbit occasionally interrupted by a quasi-satellite behavior. 2006 S.A.387 is moving in a pure horseshoe orbit. Orbits of the latter three objects are unstable and according to our calculations, these objects will leave the horseshoe state in a few hundred years. Two asteroids, 2001 QQ199 and 2004 AE9, are long-lived quasi-satellites of Jupiter. They will remain in this state for a few thousand years at least. The comets P/2002 AR2 LINEAR and P/2003 WC7 LINEAR-CATALINA are also quasi-satellites of Jupiter. However, the non-gravitational effects may be significant in the motion of these comets. We have shown that P/2003 WC7 is moving in a quasi-satellite orbit and will stay in this regime to at least 2500 year. Asteroid (118624) 2000 HR24 will be temporarily captured in a quasi-satellite orbit near 2050 and we have identified another one object which shows similar behavior - the asteroid 2006 UG185, although, its guiding center encloses the origin, it is not a quasi-satellite. The orbits of these two objects can be accurately calculated for a few hundred years forward and backward.

7

Determination of the classical orbital elements of the perturbed and perturbing planets from first principles. Part I: Outline

Kamel O. M.

Mechanics and Mechanical Engineering

|

2011

|

Vol. 15, nr 2

193-195

EN

In this outline we present a rather simple method to solve the planetary perturbation problem. We do not avoid the introduction of the expansion of the planetary disturbing function, the formulae of the elliptic expansions and the truncation of the Poisson series at the desired degree. We should remark that all orders of magnitude of the masses of the planets are taken into consideration, which is a very important result of this approach which we encounter in the order by order approach of planetary theory.

8

A Combined Method to Compute the Proximities of Asteroids

Šegan S., Milisavljević S., Marčeta D.

Acta Astronomica

|

2011

|

Vol. 61, No. 3

275--283

EN

We describe a simple and efficient numerical-analytical method to find all of the proximities and critical points of the distance function in the case of two elliptical orbits with a common focus. Our method is based on the solutions of Simovljević's (1974) graphical method and on the transcendent equations developed by Lazović (1993). The method is tested on 2 997 576 pairs of asteroid orbits and compared with the algebraic and polynomial solutions of Gronchi (2005). The model with four proximities was obtained by Gronchi (2002) only by applying the method of random samples, i.e., after many simulations and trials with various values of elliptical elements. We found real pairs with four proximities.

9

Librations with Mass Transfer in the Sun-Jupiter System

Horedt G. P., Oproiu T.

Acta Astronomica

|

2005

|

Vol. 55, No. 3

321--329

EN

Trojan-type motion is analytically and numerically studied under mass transfer between the primaries with conservation of their total orbital angular momentum. We prove theoretically and numerically our new result that angular libration widths change as m1/4, (m - Jupiter mass) if they are throughout smaller than about 60°. Numerical examples show that for initial libration widths larger than about 60°, the Trojan is ultimately driven out of the libration domain, becoming an ordinary asteroid, if Jupiter's transferred mass increases by a factor less than about two. Certain processes occurring in our solar system and in extrasolar planetary systems lead to a decrease of the Trojan's libration amplitude, while other processes lead to an increase, respectively.

10

Warsaw Ephemeris of the Solar System: DE405/WAW

Sitarski G.

Acta Astronomica

|

2002

|

Vol. 52, No. 4

471--486

EN

An ephemeris of the Solar System in rectangular coordinates is produced by numerical integration of equations of motion of nine planets, the Moon, and the Sun. Recurrent power series method of 26th order is applied when integrating the equations of motion in barycentric equatorial coordinates. Initial data of the JPL DE405 ephemeris were used to prepare the starting data for our integration. A comparison with the JPL ephemeris shows that our ephemeris gives e.g., the solar coordinates in accordance to within ±5×10-8 a.u. in the interval of thousand years. Starting data for integration of equations of motion of five outer planets were prepared. Initial values of barycentric coordinates and velocity components for Ceres, Pallas, Vesta, and Hygiea were also found on the base of a large number of astrometric observations of those asteroids. A subroutine providing the planetary coordinates and velocity components for any date may be included as a source of necessary planetary data in computer routines for orbital computations. For a convenient practical use, we stored values of coordinates and velocity components of the Solar System in a file for 1001 dates from 1493 January 25.0 to 2150 March 11.0 every 240 days to choose the proper starting data for planetary integration. Examples of the orbital computations using the DE405/WAW ephemeris are presented.

11

2060 Chiron - Chaotic Dynamical Evolution and its Implications

Gabryszewski R.

Acta Astronomica

|

2002

|

Vol. 52, No. 3

305--216

EN

2060 Chiron - one of the Centaurs orbiting chaotically among the giant planets - is treated as an asteroid and a comet (95P/Chiron) as well. Since the day of the discovery many papers have discussed its past and future fate. In this paper a possibility of Chiron's dynamical evolution to different cometary orbital types is studied. An ensemble of orbital elements was used to describe Chiron's dynamics in terms of probability. The ensemble was generated using a unique scheme of elements creation. Dispersion of elements obtained by this method is much smaller compared to ranges obtained by varying the original elements in the ellipsoid of their mean errors. The chaos in Chiron's dynamical evolution can be seen in 5 to 9 kyrs, although the dispersion of orbital elements is small. Halley type orbits are the rarest noticed orbital types but the number of these objects is three times greater than the number of apparent Halley type comets. The variations of probability of different cometary orbits as a function of time is also presented. The rate of HTC orbit production is only four times lower than the production rate of JFCs after the first 50 kyrs of integration. Remarks on the small body transportation mechanisms are also included.