THE  BUCHAREST  OBSERVATORY  OF  THE  ASTRONOMICAL  INSTITUTE  AT  CENTENARY:  100  YEARS  AND  MORE 
OF  ROMANIAN  ASTRONOMY

MAGDA  STAVINSCHI,  VASILE  MIOC

Astronomical Institute of the Romanian Academy

Str. Cuţitul de Argint 5, 040557 Bucharest, Romania

E-mail: magda@aira.astro.ro, vmioc@aira.astro.ro

Abstract. On 1 April 1908 the Astronomical Observatory of Bucharest was set up. But the Romanian astronomy is much older. There are evidences that go
back to the dawn of the first millennium. The 19th century brought the modernization of Romanian astronomy in European context. By coincidence, another
observatory was set up the same year on a Romanian territory (today in the
Republic of Moldavia), that of Nicolae Donici. This paper constitutes itself in a
survey of the most important events and personalities of the Romanian astronomy, especially in the context of the new international cooperation wave in which

Romania
participates.

Key words: history of astronomy – Romanian astronomy – centenary of the Bucharest Astronomical Observatory.

 

 

 

EVALUATION  OF  ASTROPHYSICALLY  USEFUL  PARAMETERS  FOR  LaO  MOLECULE

PONSAMY  SRIRAMACHANDRAN1,  RAMACHANDRAN  SHANMUGAVEL1,  NARAYANAN RAJAMANICKAM1,  SOMASHEKAR  PUNDALIKARAO  BAGARE2

1Physics Research Centre, VHNSN College, Virudhunagar - 626 001, India

E-mail: nrmanickam@rediffmail.com

 

2Indian Institute of Astrophysics, Kodaikanal and Bangalore - 560 034, India

Abstract. Vibrational transition probabilities namely Franck-Condon (FC) factors and r-centroids for the band
C2Π3/2–A
2Δ5/2, C2Π1/2–A2Δ3/2, C2Π3/2–X2Σ+, and C2Π1/2–X2Σ+, systems of Lanthanum Oxide (LaO) molecule
have been calculated. They are very closely related to transition probabilities, which have been evaluated by the more
reliable numerical integration using a suitable potential. In each electronic state, wave functions are computed for all
observed vibrational levels by numerical solution of the radial Schrödinger equation in which the potential energy function
is calculated at equally spaced intervals of 0.01
Ǻ in the range of nuclear separation range. The effect of high rotational
quantum numbers on FC factors has been studied. The vibration-rotation interaction (VRI) on the FC factors of molecular
band systems is negligible for relatively low rotational quantum numbers (J). Values of FC factors and r-centroids are given
for all allowed bands of each system, and the available band wavelengths are also entered in the respective tables.

Keywords: LaO, Franck-Condon factors, r-centroids.

 

 

 

ON  THE  STABILITY  OF  PLANETARY  ORBITS  WITH  A  MODIFIED  HERMITE  INTEGRATOR

OVIDIU C. FURDUI

Astronomical Institute of the Romanian Academy

Astronomical Observatory Cluj-Napoca

Str. Cireşilor 19, 400487 Cluj-Napoca, Romania

E-mail: ovidiu.furdui@gmail.com

Abstract. We present the results of very-long-term numerical integrations of planetary orbital motions over 1010 yr time including
all nine planets. A quick inspection of our numerical data shows that the planetary motion, at least in our simple dynamical model,
seems to be quite stable even over this very long time-span. A closer look at the lowest-frequency oscillations, using a low-pass
filter, shows us the potentially diffusive character of the terrestrial planets’ motion, especially that of Mercury. However, there are
no apparent secular increases of eccentricity or inclination in any orbital elements of the planets, which may be revealed by still
longer-term numerical integrations. We have also performed a couple of trial integrations including the motions of the outer five
planets over the duration of 5
×1010 yr.

Keywords: celestial mechanics – N-body problem – Solar System dynamics – stability.

 

 

 

LIBRATION  POINTS  IN  FOCK’S  RESTRICTED  THREE-BODY  PROBLEM

Vasile  Mioc 1,   Rodica  Roman 2

 

Astronomical Institute of the Romanian Academy

Str. Cuţitul de Argint 5, 040557 Bucharest, Romania

E-mail: vmioc@aira.astro.ro

 

Astronomical Institute of the Romanian Academy

Astronomical Observatory Cluj-Napoca

Str. Cireşilor 19, 400487 Cluj-Napoca, Romania

E-mail: rroman@math.ubbcluj.ro

Abstract. We tackle the circular restricted three-body problem within the framework of Fock’s field, associated to a potential
of the form A1/r + A2/r2 + A3/r3 + A4/r4. We establish the equations of motion and prove the existence of an analog of the Jacobian
first integral. After emphasizing some features of the zero-relative-velocity surfaces, we approach the main topic: libration points.
As in the Newtonian case, there are three collinear libration points, and, if they exist, two triangular libration points (situated in the
orbital plane of the primaries). We give the expressions of the positions of all these points. If triangular points exist, they may not
form equilateral triangles; the triangles are isosceles for equal masses of the primaries, and scalene else.

Key words: celestial mechanics – restricted three-body problem – libration points – Fock’s field.

 

 

 

BIELLIPTIC  TRANSFER  WITH  PLANE  CHANGES

MOHAMED  ADEL  SHARAF

Department of Astronomy, Faculty of Science, King Abdul Aziz University

80203 Jeddah, Saudi Arabia

E-mail: sharaf_adel@hotmail.com

Abstract. The most powerful technique that has been devised for optimal plane change maneuvers is known as the third-body
driven technique. This technique can be viewed as classical bielliptic plane changes (or restricted three-impulse plane change)
with the apoapsis maneuver suppressed by the use of the third-body forces. In the present paper, full analysis of the bielliptic
plane changes maneuver (BPCM) is developed, as well as its importance as the basis of the third-body driven technique.
As to the computationally developments, we established new formula to estimate the initial guess for the iterative solutions
of the fundamental equations of BPCM. This formula not only secures the convergence of the solutions, but also it could be
used to accelerate the convergence. Finally, some numerical examples are included.

Key words: astrodynamics – orbital transfer maneuvers – trajectory optimization.

 

 

 

DETERMINATION  OF  A  CELESTIAL  PLANE  ORIENTATION:  APPLICATION  TO  MILKY  WAY

MOHAMED  ADEL  SHARAF

Department of Astronomy, Faculty of Science, King Abdul Aziz University

80203 Jeddah, Saudi Arabia

E-mail: sharaf_adel@hotmail.com

Abstract. We develop a general analytical method for the determination of any celestial plane orientation of objects with respect to
a fundamental plane at a certain epoch. This plane is defined as the plane of greatest condensation of these objects. The method is
applied for the determination of: the equatorial coordinates of the galactic pole and
the inclination of the Milky Way plane to the
celestial equator and the right ascension of its ascending node, all
for the epoch 2000.0.

Key words: astrometry – ephemerides – galactic structure.

 

 

 

PRECISE  DETERMINATION  OF  MINOR  PLANET  POSITIONS

GHEORGHE  BOCŞA1,  MILCHO  TSVETKOV2

1 Astronomical Institute of the Romanian Academy

Str. Cuţitul de Argint 5, 040557 Bucharest, Romania

E-mail: gbocsa@aira.astro.ro

 

2 Institute of Astronomy of the Bulgarian Academy of Sciences

72, Tsarigradsko Shosse Blvd, 1784 Sofia, Bulgaria

E-mail: milcho@skyarchive.org

Abstract. We perform a first comparative study concerning position determination of selected minor planets observed in Bucharest.
Photographic observations were made with the equatorial refractor (d = 0.38 m, f = 6 m). The plates were measured with a Carl-Zeiss
Ascorecord machine and digitized with an Epson 1640XL flatbed scanner. We compare manual measurements with data processing of
digitized plates for five asteroids.

Key words: astrometry – photographic observations – digitization.

 

 

 

NEW  LAWS  OF  PLANETARY  DISTANCES

IVAN  KOTLIAROV

Faculty of Geography and Geoecology, St. Petersburg State University

197101 Do Vostrebovaniya, St. Petersburg, Russia

E-mail: lrpg@mail.ru

Abstract. The present paper gives a detailed analysis of the new formulation of Titius-Bode law by Poveda and Lara (2008) and
of the hypothesis that this law may exist in extra-solar planetary systems. A thorough study of the correspondences between the
predicted distances and the observed ones in the Solar System and in 55 Cancri is given. A less known formula of planetary
distances – Butusov’s (1973) law – is discussed. New predicted distances in 55 Cancri based on Butusov’s law are proposed.

Key words: Titius-Bode law – planetary systems.

 

 

 

FROM  SYNCHRONIZATION  OF  THE  ATOM  TO  ORGANIZATION  OF  THE  UNIVERSE  VIA  GRAVITATION

GERD  HELMECKE 1,  ULRICH  HERKENRATH 2

1 Königstr. 4, D-53773 Hennef, Germany

E-mail: dok-helmecke@t-online.de

 

2 Universität Duisburg-Essen, FB Mathematik

Lotharstr. 65, D-47057 Duisburg, Germany

E-mail: ulrich.herkenrath@uni-due.de

Abstract. This paper is a contribution to develop a unified theory for the basic physical forces of nature. A model in the sense of a scientific
hypothesis is designed, in which the gravitational force is explained as an electromagnetic effect. We take the following approach: the force,
which is called gravitation, is effective between any masses, therefore between atoms, too. This leads us to the idea to study the interaction
of atoms in order to find causes for the gravitational force, i.e., an attractive force between them. Since electromagnetic forces are effective
on that scale, mass is equivalent to energy, and general experience in physics recommends to try to explain phenomena with as few causes
as possible, we analyze the interaction of atoms under electromagnetic aspects. Based on the hypothesis of a certain kind of “synchronization”
of the atom and taking into account the electron sheath as a rotating system of charges, we explain the attractive force between atoms as an
electromagnetic effect. The explanation of gravitation, which we present here, together with basic cosmic laws presented in a previous paper
(Helmecke and Herkenrath 2003), leads to important consequences for the understanding of dark matter, black holes and the evolution of the
Universe.

Key words: gravitation – unified theory – synchronization of the atom – dark matter – black holes – evolution of the Universe.