MAGDA STAVINSCHI1, WILLIAM van ALTENA2
1 Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
magda@aira.astro.ro
2 Yale
University,
E-mail:
vanalten@astro.yale.edu
Abstract. The future of
astrometric research is very exciting due to the SIM
and GAIA astrometric space missions, which will provide
10–20 microarcsecond
positions, parallaxes and proper motions for 109 stars.
Innovative
ground-based telescopes, such as the LSST,
are planned, which will provide less
precise data for many more stars. The potential for studies of the
structure,
kinematics and dynamics
of our Galaxy as well as of the physical nature of
stars and of the cosmological distance scale is without equal in the
history of
astronomy.
Hipparcos and the HST were astrometric successes only due to the
dedicated work of specialists in astrometry that fought to maintain the
astrometric characteristics of those satellites and their data
pipelines. It is
ironic therefore that given this unparalleled treasure trove of data,
in two
years not one course in astrometry will be taught in the US, leaving
all
astrometric education to Europe, China and Latin America.
Who will ensure the
astrometric quality control for the JWT, SIM, GAIA, LSST, to say
nothing about
the current large ground-based facilities,
such as the VLT, Gemini, Keck, NOAO,
Magellan, the LBT, etc.? We propose a renewal of astrometric education
in the
universities to prepare
qualified scientists for these unique opportunities so
that the scientific returns from the investment of several billions of
dollars
will be maximized.
The universities, observatories and agencies should
acknowledge their responsibility to hire qualified full time
astrometric
scientists to supervise
existing and planned astronomical facilities so that
quality data should be obtained. The funding agencies are providing
outstanding
facilities.
Will the universities, institutes and observatories assume their
responsibilities?
Key words: astrometry – education.
GROUND-BASED
ASTROMETRY AT
THE TIME
WILLIAM
THUILLOT1,
JEAN-EUDES ARLOT1, MAGDA
STAVINSCHI2,
MIREL BIRLAN1,2, VALERY
LAINEY1,3
1 Institut
de Mécanique Céleste et de Calcul des
Éphémérides
IMCCE/Observatoire
de Paris
77
av. Denfert
Rochereau F-75014 Paris, France
E-mail:
thuillot@imcce.fr,
Jean-Eudes.Arlot@obspm.fr
2 Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
magda@aira.astro.ro
3 Royal
Observatory of
Av.
Circulaire, 3 – Ringlaan 3, B-1180
Bruxelles –
Abstract. The next space astrometry mission GAIA will be launched
before 2012
with the purpose to perform a wide 3-D cartography
of the Galaxy. During this 5
years long mission many Solar-System objects will be scanned and
measured. Each
object will be observed
about one hundred times and a very accurate astrometry,
down to 10 µas, will be carried out. Furthermore, since the
limiting magnitude
will be 21 and observations could be made rather close to the Solar
direction,
many new Solar-System objects will certainly be discovered.
Therefore this mission will be a milestone in
particular for astrometry of the Solar System. Several ground-based
programs of
observation
of Solar-System objects will probably have to be stopped or
reoriented in order to remain relevant. Our paper intends to discuss
these
circumstances and the relevance of selected observations. Several
proposals are
made for coordinating efforts in order to get a better
knowledge of these
objects. Either autonomous programs or programs complementary to the
GAIA
mission are proposed. Small telescopes
will be still very useful for these
programs.
Key words: space mission – astrometry – catalogue – follow-up.
GAMMA-RAY
BURST AFTERGLOW
STUDIES IN
Mehmet
EMIN ÖZEL1, Yasemin
KAÇAR1, Volkan BAKIŞ1,
Murat OLUTAŞ2, Umit
KIZILOĞLU3, Tolga GÜVER4
1 Çanakkale
Onsekiz Mart University,
Department of Physics,
E-mail:
m.e.ozel@comu.edu.tr
2 Abant
İzzet
3
4 University
of
Abstract. Gamma-Ray
Bursts (GRBs), accidentally discovered by Vela satellites forty years
ago, are
transient celestial events, lasting
milliseconds to tens of minutes. They are
the most powerful explosions in the whole Universe. About once per day,
at a
random location
in the sky, a shower of gamma-ray photons with 1 keV – 100 MeV
energy appears and we cannot guess where they will occur next.
Hence their
observing and studying were hard. To overcome these difficulties,
astronomers
designed special-purpose detectors such as
Robotic Optical Transient Search
Experiment (ROTSE). To understand these events, scientists need to
study afterglow
emissions in X-rays,
optical and radio waves after or during a GRB. The ROTSE
Project aims at achieving the detection of optical afterglow emission
from the
GRB. The ROTSE system can move quickly on the coordinates of the burst,
which
is usually announced through Internet. Presently, the
international ROTSE
collaboration includes the main coordinating group (running a station
at
Namibia
Antalya
afterglow detection statistics, the properties, goals,
functions and the technology behind the Global ROTSE system installed
around
the world
will be summarized, with emphasis on
Key words: Gamma-Ray astronomy – Gamma-Ray Bursts – GRB afterglow emissions – GCN – BATSE – ROTSE.
NARROW-FIELD
ASTROMETRY
PETRE Popescu1, RADU Popescu1, Gheorghe BocŞa1, PETRE Paraschiv1, GHEORGHE Huian2, ALIN Nedelcu1, LIVIU ŞerbĂnescu1, OCTAVIAN BĂdescu1
1 Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
petre@aira.astro.ro
2 INCDMF-CEFIN
Şos.
Pantelimon 6–8,
Bucharest, Romania
E-mail:
cefin@cefin.ro
Abstract.
Early results of
narrow-field CCD astrometry with a new CCD camera Apogee AP47P are
presented.
Despite the small field of view
(7.3×7.3 arcmin), a limiting magnitude of ~18
provides us stars enough to complete the astrometrical tasks. For the
same
reason we were obliged
to use catalogues with a denser stellar coverage as USNO
A1.0 or the newer USNO B1.0, which include proper motions. All the
images are
reduced using IRAF package software.
Key
words: narrow
field astrometry– limiting magnitude – data reduction.
ASTROMETRIC SOLUTIONS OF ECLIPSING BINARIES: R CMA AND XY LEO
VOLKAN BAKIŞ, EDWIN BUDDING, OSMAN DEMİRÇAN, HİCRAN BAKIŞ
Physics Department, Faculty of Science & Arts
E-mail:
bakisv@physics.comu.edu.tr
Abstract. Astrometric
solutions, together with times of minimum, have been
made for R CMa (HIP35487) and XY Leo (HIP49136)
to identify the wide companions
to the eclipsing pairs. From these solutions, we derive the inclination
of the
wide orbit as 91°.7 ± 4.7
and 94°.4 ± 0.2 and the masses of the third bodies as 0.36 ± 0.2 and 0.98 ± 0.2
solar masses for R CMa and XY Leo, respectively.
This study confirms that the
light-time travel effect can explain the sinusoidal O – C variation of
the
eclipsing systems.
Key words: eclipsing binary systems – triple systems – astrometry – light time effect.
COOPERATION FOR COMMON
USE OF SEE
ASTRONOMICAL DATABASE
AS A REGIONAL
VIRTUAL OBSERVATORY
IN DIFFERENT
SCIENTIFIC PROJECTS
GENNADY PINIGIN, YURI PROTSYUK, ALEXANDER SHULGA
Nikolaev Astronomical
Observatory
Str. Observatorna 1, 54030
Mykolajiv-30,
E-mail:
yuri@mao.nikolaev.ua
Abstract. The
activity of scientific collaborative and co-operative research between
South-Eastern European (SEE) observatories is enlarged in the last
time.
The
creation of a common database as a regional virtual observatory is very
desirable. The
creation of
astronomical information resource with a capability of
interactive access to
databases and telescopes on the base of the general astronomical
database of
the SEE countries is presented. This resource may be connected
with the
European network. A short description of the NAO database is presented. The total amount
of
the NAO information makes about 90 GB, the one obtained
from other sources –
about 15 GB. The mean
diurnal level
of the new astronomical information produced with the NAO CCD
instruments makes
from 300 MB
up to 2 GB, depending on the purposes and conditions of
observations. The
majority of observational data is stored in FITS format. Possibility of
using
of VO-table
format for displaying these data in the Internet is studied.
Activities on development and the further refinement of storage,
exchange and
data processing standards
are conducted.
Key words: astronomical database – virtual observatory.
COOPERATION
FOR GROUND-BASED
PROVISION OF
THE PROGRAMME “GAIA
FOLLOW-UP” WITHIN
THE INTERNATIONAL
FRAMEWORK OF
KSU (
ZEKI ASLAN1, RUSTEM
GUMEROV2, IREK KHAMITOV1,
GENNADY PINIGIN3, ALEXANDER SHULGA3
1 Turkish National Observatory
TUG,
Akdeniz
E-mail: aslan@tug.tug.tubitak.gov.tr
2
E-mail:
rgumerov@ksu.ru
3 National Astronomical Observatory
E-mail:
pinigin@mao.nikolaev.ua
Abstract. In a joint
project of international collaboration between KSU (
Solar System
bodies down to 20 magnitudes connected with GAIA project are planned
using the
1.5 m telescope RTT150 equipped with CCD cameras and computer
control.
Additionally, observations of the brighter objects (down to 18 mag)
will be
made with the CCD telescopes of NAO. It is stressed that an alert
system of
observations
seems to be necessary in order to catch more data on these targets
and follow-up from the ground. Photometric
observations of occultations of stars by asteroids are also planned.
Key words: astrometry – photometry – small Solar System bodies.
NEAR-IR
SPECTROSCOPY
OF KARIN FAMILY
Mirel Birlan 1,2
1 Institut
de Mécanique Céleste et de Calcul des
Ephémérides, Observatoire de
Paris
77
av.
Denfert-Rochereau, 75014 Paris Cedex, France
E-mail:
Mirel.Birlan@imcce.fr
2 Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
Abstract. The asteroid 832
Karin belongs to the large family of Koronis,
located in the main belt. Cluster analysis and tests performed
by Nesvorný et
al. (2002) and Nesvorný and Bottke (2004), reveal a family of
asteroids grouped
around 832 Karin. Backward numerical
integrations unveiled their orbits
convergence to the same orbital elements only 5.7 million years ago.
This could
be the consequence of the
breakup produced by the collision of two bodies from
the main belt and thus, the youngest family if asteroids ever known.
Our
purpose was
to investigate the spectral region 0.8–2.5 micron in order to
obtain information concerning the physics and mineralogy of Karin
members. The
paper presents preliminary results of near-IR spectroscopy for three of
this
family members: 832 Karin, 13765
Nansmith and 13807 (1998 XE13).
Key words: asteroid – family – spectroscopy.
IMAGE PROCESSING OF HIGH-SPEED CELESTIAL OBJECTS
ALIN NEDELCU, RADU POPESCU, OCTAVIAN BĂDESCU
Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
{nedelcu, pradu,
octavian}@aira.astro.ro
Abstract. In order to show
the capabilities of the modernized astrograph,
some observational tests of high-speed objects were performed.
The exposure
time and the highly accurate metrology system have been conceived in
order to
monitor, focus on, and track the high-speed
objects. The ultra-sensitive CCD
camera based on a back illuminated chip, allows to this instrument to
“track”
celestial objects up to
18 magnitudes, summing images with an exposure time
that does not exceed 10 minutes.
Key words: astrometry – high-speed objects – CCD tracking.
STUDY OF THE MAGNITUDE EQUATION IN NOVA STARS OBSERVATIONS
Valerian SementSov,
Irina VolosHina
Sternberg
Astronomical Institute
Universitetskij
Prospekt 13,
E-mail:
vib@sai.msu.ru
Abstract. The preliminary results of determination of the magnitude-coordinates dependencies from CCD observations of two recent novae are presented.
Key words: variable stars – nova stars – CCD data – magnitude equation.
MIGRATION VELOCITIES
OF ASTEROIDS
ANATOLY KAZANTSEV
Astronomical
Observatory of
Str.
Observatorna 3, 04053
E-mail:
ankaz@observ.univ.kiev.ua
Abstract. Numerical
calculations of evolution of some thousands asteroid
tentative orbit in the zones of commensurabilities with Jupiter
with account of
nine planets and three asteroids are performed. The integration
intervals
reached 300 thousand years. Some orbits transfer
to NEAs orbits, and some – to
similar to Centaurs’ ones. Migration
velocities of asteroids from MBA to NEAs and Centaurs are estimated.
Key words: asteroids – commensurability – Centaurs – near-Earth asteroids.
CHAOTIC DYNAMICS OF ASTEROIDAL SATELLITES
DAN
ŞELARU1, VASILE MIOC2, CĂTĂLIN
CUCU-DUMITRESCU1, MARIAN
GHENESCU1
1Institute for Space Sciences
Str.
Mendeleev 21-25, 010362
E-mails:{danselaru,
cucudumitrescu}@yahoo.com,
mariang@softrust.ro
2Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
vmioc@aira.astro.ro
Abstract. We use the
planar, circular, restricted three-body problem (with a
Schwarzschild-type field generated by the primary) to
model the dynamics of a
moonlet around a prolate asteroid under the perturbative influence of
the Sun.
We show that there exists a
continuous range of parameters for which the
“unperturbed” problem asteroid-satellite admits a homoclinic orbit. We
estimate
the
Melnikov integral for the perturbed problem, showing that it has simple
zeroes. This means chaotic behaviour (unpredictable motion)
of the moonlet for
an open set of initial data.
Key words: celestial mechanics – asteroidal satellites – chaotic dynamics.
PERSISTENCE
OF PLANETARY RINGS UNDER
THE INFLUENCE OF
THE ANISOTROPICALLY RE-EMITTED SOLAR
RADIATION
VASILE MIOC1, MIRA-CRISTIANA ANISIU2, MAGDA
STAVINSCHI1
1 Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mails:
vmioc@aira.astro.ro, magda@aira.astro.ro
2 T.
Popoviciu Institute of Numerical
Analysis of the
P.O.Box
68,
400110 Cluj-Napoca, Romania
E-mail:
mira@math.ubbcluj.ro
Abstract. The solar
radiation has a destabilizing influence on planetary
rings. The shepherding satellites explain the persistence of these
structures,
but the observational evidence for such satellites is still very weak.
This
paper studies the existence of periodic orbits of rings’ particles
under a
strongly
destabilizing perturbing factor: the solar radiation re-emitted
anisotropically by the “landlord” planet. To this end we use Maxwell’s
model of
Saturn’s
rings, but enriching the respective potential with the terms
corresponding to the planet’s oblateness and to re-emitted radiation.
This (n+1)-body
problem
can be split into n identical two-body problems. To prove the
persistence of periodic solutions, we use two basic facts: (1) the
potential
generates a strong
force in Gordon’s sense; (2) the vector field of the problem
exhibits the symmetries Si, i = 1,2,…,7. We
prove that
for any pre-assigned period T there
exist infinitely many Si-symmetric
(i = 2,3) periodic solutions of the problem.
Key words: celestial mechanics – planetary rings– variational methods.
INVESTIGATIONS OF THE SOLAR SYSTEM SMALL BODIES AT KARAZIN KHARKIV NATIONAL UNIVERSITY
DMITRIJ LUPISHKO
E-mail:
lupishko@astron.kharkov.ua
Abstract. Astronomers of
Soviet Union
Institute
Astronomy since 2001) of Karazin
Kharkiv National University, such as: photometric studies of asteroid
shapes
and rotations; photometry and polarimetry
of M-type asteroids and their
meteorite analogues; asteroid magnitude-phase dependences and
opposition effect
of brightness; polarimetry of CMEU-asteroids
and their taxonomy;
polarization-phase dependences and opposition effect of asteroid
polarization;
UBVRI-polarimetry and spectral dependence of asteroid
polarization; scattering
properties of asteroid surfaces; optical properties and rotation of
near-Earth
asteroids (NEAs), the follow-up astrometric observations
of newly discovered
NEAs, and others. Many observational programs were carried out in
collaborations with our colleagues in Tajikistan, Crimea (Ukraine),
Poland,
Czech Republic, Germany, Italy, Sweden and the USA. Since 1995 the
comets have
also become the objects of attention of our group and polarimetric
and
photometric observations of comets are carried out regularly.
Key words: asteroids – comets – photometry – polarimetry.
OBSERVATIONS
OF STAR OCCULTATIONS
IN
Valery KLESHCHONOK1, LILYA KAZANTSEVA1, VICTOR KISLYUK2,
NICOLAY BUROMSKY1
1 Astronomical
Observatory,
E-mail: klev@observ.univ.kiev.ua
2 Main
Astronomical Observatory, NAS of
Abstract. The new
television system “Spalakh” is used for observing star
occultations in the Astronomical Observatory of the
of observation of star occultations are given. Some occultations that
show an opportunity of the television system are described in details.
The
project
of creation of the network for observation of star occultations and
mutual phenomena in planetary satellite systems with similar television
systems
is described.
Opportunities of such a network for studying the shape and
kinematics of celestial bodies are analyzed.
Key words: television observations – occultations.
DIGITAL
PLATE PRE-PROCESSING USING
FUZZY TECHNIQUES
MIHAI CARAMIHAI1, LIVIU ŞERBĂNESCU2
“Politehnica”
University
Splaiul
Independenţei 515,
E-mail:
m.caramihai@ieee.org
Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
livius@aira.astro.ro
Abstract. The
photographic plates that represent astronomical objects are scanned
with a 2400
dpi. The maximal dimension of the
plates is 24x24 cm. The scanned file
dimension is 100 Mb, taking long processing times. Taking in
consideration that
the useful information
existing on the plate is under 1% it was adopted the
translation (conversion) information method to modify it from the
existent
format in
another one that allows to store only the useful information. The
useful information was obtained applying fuzzy methods for the
recognition
of
the astronomical objects. The fuzzification/defuzzification information
methods
were analytically constituted and are based on the measurement
micrometric
machine. The observed signal was decomposed into two components: the
useful
signal (or signal of interest) and the noise. Generally,
the gray-level images
will be the threshold to calculate geometrical measures such as area,
perimeter, diameter, compactness, etc. of an object.
The standard approach to
image analysis and recognition begins by segmenting the image into
regions and
computing various properties of and
relationships among these regions. It is
not always obvious how to measure geometrical properties of fuzzy sets,
but
definitions have been given and
basic properties established for a variety of
such properties and relationships, including connectedness and
surroundness,
convexity, area, perimeter
and compactness, extent and diameter. The final
information, obtained with fuzzy techniques, is represented by the
relative
position and relative
magnitude of the astronomical objects identified on the
photographic plate.
Key words: fuzzy logic – image reconstruction – filtering – pre-processing.
ASTROMETRIC PLATE CATALOGUES IN THE WFPDB
KATYA TSVETKOVA 1, MILCHO TSVETKOV 1, MAGDA STAVINSCHI 2,
ALAIN
FRESNEAU 3, PATRICIA
LAMPENS 4
1 Institute of
Astronomy,
72
Tsarigradsko Shosse Blvd., Sofia-1784, Bulgaria
E-mail: katya@skyarchive.org
2
Astronomical Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
magda@aira.astro.ro
3 Astronomical
Observatory, Strasbourg
11,
rue de
l'Université, 67000 Strasbourg, France
E-mail:
fresneau@astro.u-strasbg.fr
4 Royal
Observatory of
3
Ringlaan, B-1180
E-mail:
patricia.lampens@oma.be
Abstract. The astrometric
plate catalogues included in the Wide-Field Plate
Database (WFPDB, http://www.skyarchive.org) are presented.
The WFPDB with its 375 archives, containing more
than 2 130 000 plates obtained with professional telescopes of 125
observatories worldwide,
is now the basic source of information for the
archived observations. Their importance is in connection with analyzing
of the
long-term variations
(sometimes more than a century) of the positions, orbits
or dimensions of a lot of celestial objects or their prediscovery
history. At
present there
is an on-line access to the descriptive data for 377 687 plates
from 92 archives through the WFPDB updated version in the Sofia Sky
Archive
Data Center (SSADC). Archives of selected digitized plates are under
preparation.
Key words: astrometry –astrometric catalogues – databases – Carte du Ciel project.
COMPILED CATALOGUE OF REFERENCE STARS AROUND 43 EXTRAGALACTIC RADIO SOURCES
Vladimir Rylkov1,
Anna DementYeva1,
NaTALIa
NarizhnaYa1,
Nadezhda MAIGUROVA2,
Gennady Pinigin2,
Yuri Protsyuk2,
Gheorghe BocŞa3, Petre Popescu3
1 Main
Astronomical Observatory of the
Pulkovskoe
Shosse 65/1, 196140 St.
Petersburg-140,
E-mail: vryl@gao.spb.ru
2 Nikolaev Astronomical Observatory
Str.
Observatorna 1, 54030 Mykolayiv-30,
E-mail: pinigin@mao.nikolaev.ua
3 Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
petre@aira.astro.ro
Abstract. Some
differential catalogues of reference stars around extragalactic radio
sources
obtained from photographic and CCD
observations by different observatories are
considered. A compiled catalogue of star positions in fields 30'x 30'
for the
reduction of
optical observations ERS on telescopes endowed with CCD cameras is
intended. Photographic observations fields around of 74 ERS
were made in
Pulkovo observatory, around 115 ERS – in observatory of Kiev
university, around
188 ERS – in the Astronomical Institute
of the Romanian Academy in Bucharest,
208 fields around ERS in Nikolaev observatory on telescope with CCD
camera were
obtained.
As first results the reduction techniques for results of observations
to uniform compiled catalogue are shown. Astrometric positions for 5500
stars
brighter than 16 magnitude for 43 fields around ERS are presented. A
comparison
of our results with those of other authors is made.
Key words: astrometry – reference stars – extragalactic radio source field.
Relative positioning of
geoid-ellipsoid
Octavian BĂdescu1,2, PETRE
POPESCU2, RADU POPESCU2
1 Technical University of Civil Engineering
Bd.
Lacul Tei 124,
E-mail:
octavian@aira.astro.ro
2 Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040558 Bucharest, Romania
E-mail: petre@aira.astro.ro, pradu@aira.astro.ro
Abstract. The angular differences between
local vertical
direction (plumb line) defining the geoid, and normal to the ellipsoid
surface,
also called vertical deflection, are not negligible at all. These
differences
can reach sometimes values of tens of arcseconds. Astro-geodetical
methods of
determining vertical deflection are more effective for local accurate
geoid
determination than other methods, i.e. gravimetry.
Nowadays, the astro-geodetic
compilation of the geoid can be done in absolute values, by combining
GPS
satellite techniques with star
tracking CCD technology. Through the
introduction of an adequate matrix of weights, we take into account the
unequal
weights of all
direct measurements: angular measurements and times at the
chronometer. Applying the theory of conditional measurements with
unknowns,
we
get a rigorous algorithm for the determination with maximum efficiency
of all
three fundamental elements of astronomical geodesy.
Key words: astrometry – geodesy – astronomy – vertical deviation.
ASTROMETRY
IN
NATALIYA BAZYEY
Odessa
Astronomical Observatory, Odessa, Ukraine
E-mail:
Ii1966@mail.ru
Abstract. We present a
survey of the astrometric activities in Odessa
University Observatory. On the basis of the meridian observations
with the
Repsold meridian circle, the collaborators of the observatory published
about
40 catalogues of accurate stellar positions.
The importance of cooperation with
other astronomical institutions (Pulkovo,
Key words: astrometry – observations – meridian circle.
SHIP’S COORDINATES VIA SOLAR CIRCUMMERIDIAN OBSERVATIONS
STELIAN COJOCARU, FLAVIUS OTINCELESCU, ADRIAN DRĂGUŞAN
“Mircea
cel Bătrân”
Str.
Fulgerului 1–3,
E-mail:
cojocarus@yahoo.com
Abstract. We introduce an
original method used to determine the ship’s
astronomical position based on Sun’s altitude measurements
near the meridian
passage. The paper introduces the classical method of Saint-Hillaire
for
determining the ship’s position from
simultaneous measurements to heavenly
bodies and analyses a practical example comprising 33 measurements used
both to
determine
the ship’s position and to evaluate the results.
Key words: solar observations – navigation.
ASTROMETRY WITH THE 50/70 SCHMIDT TELESCOPE OF THE BULGARIAN NATIONAL ASTRONOMICAL OBSERVATORY – ROZHEN
VIOLETA Ivanova1, TANYU
Bonev1, GORDANA Apostolovska2,
GALIN
Borisov1,
1 Institute
of Astronomy,
72,
Tsarigradsko
Chaussee Blvd., BG-1786 Sofia, Bulgaria
E-mail:
ivanova@astro.bas.bg
2 Institute of Physics, Faculty of Natural Sciences and Mathematics
E-mail:
gordanaa@iunona.pmf.ukim.edu.mk
Abstract. We
present the main results from astrometric observations of asteroids
made at the
Bulgarian National Astronomical
Observatory – Rozhen. We discuss the first observations
with the Schmidt telescope in scanning mode for search of asteroids.
Key words: astrometry – asteroids – comets.
PLANETARY RINGS STABILITY: QUALITATIVE APPROACH
VASILE
MIOC, MAGDA STAVINSCHI
Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
vmioc@aira.astro.ro, magda@aira.astro.ro
Abstract. We tackle
Maxwell’s (n+1)-body problem
within the case of an
oblate central planet. Such a problem can be split
into n identical two-body problems, whose solution is
already known. The
cases of stable periodic and quasiperiodic motions
are pointed out. These
results are valid for both rings and massive satellites.
Key words: celestial mechanics – planetary rings and satellites – stability.
RT AND:
MULTIPERIODIC ORBITAL PERIOD VARIABILITY, RESONANCE,
AND THE HYPOTHESIS
ALEXANDRU POP, RODICA ROMAN
Astronomical
Institute of the
Astronomical
Observatory Cluj-Napoca
Str.
Cireşilor
19, 400487 Cluj-Napoca, Romania
E-mail:
apop@academie.cj.edu.ro,
rroman@math.ubbcluj.ro
Abstract. The preliminary
analysis of the photoelectric times of primary minimum light of RT And
through
the methodology used in case of pulsating stars
revealed a possible
multiperiodic behaviour of its orbital period variability, with
possible 3:1
and 5:1 resonance phenomena. The interpretation of the
emphasized periodicities
29.4 yr, 9.56 yr, and 5.860 yr found in the O – C curve as
caused by the
light-time effect led to M sin i
values for the hypothetical
companions
of 11.77, 5.53, and 3.97 MJupiter,
respectively.
Key words: variable stars – eclipsing binary systems – period variability – light-time effect.
ROMANIAN INSTRUMENTS AND DATABASES: AN ATTEMPT TO CAPITALIZE THE ASTRONOMICAL HERITAGE
PETRE POPESCU, GHEORGHE BOCŞA, ALIN NEDELCU
Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
[petre, gbocsa,
nedelcu]@aira.astro.ro
Abstract. The most valuable
things of our astronomical heritage are
instruments and databases. The formation of databases, the storage and
format
were performed under the super vision of the Wide-Field Archives
Database UAI
Working Group. Databases were organized and resized
in better condition being
able to be used. Most of instruments are the living images of an epoch,
of
former methods and observation procedures.
In spite of time, there are some
optical qualities, which must be taken into account. Depends on
astronomers’
skill whether they preserve an instrument
or not. An analysis of the optical
and mechanical system must be performed to evaluate whether the
instrument can
be modernized, or must be
preserved in the original shape. The paper shows some
results obtained at the Astronomical Institute of the
Key words: instruments –databases.
HELEN ROVITHIS-LIVANIOU1, PETER ROVITHIS2, LEONIDAS GEORGOPOULOS1,
DAVID MKRTICHIAN3
1 Section of Astrophysics-Astronomy & Mechanics, Dept. of Physics, Athens University Panepistimiopolis, Zografos 157 84, Athens, Greece
E-mail:
elivan@ cc.uoa.gr
2 Institute
of Astronomy and Astrophysics, National Observatory of
3 Astronomical
Observatory,
Shevchenko
Park, 65014 Odessa, Ukraine
Abstract. The light curves of the eclipsing binary TZ Dra,
obtained with the 40-cm Cassegrain reflector of the
ST8/SBIG CCD camera equipped with four filters (BVRI) in 2002, are
analyzed
and discussed. A set of preliminary elements for TZ Dra
was found, and there
are indications that the primary component of this binary is a
pulsating
variable.
Key words: eclipsing binaries – light curve analysis – TZ Dra.
CCD observations of
comets
Vitaly Filonenko, Fiodor Velichko, Sergey Velichko, Roman Krymsaljuk
Astronomical
Institute of
Sumskaja
str. 35,
Kharkov, Ukraine
E-mail:
filonenko@astron.kharkov.ua
Abstract. Some results of
astrometric CCD observations of four comets are
presented. On the basis of the astrometric and photometric
CCD observations of
comet C/2001 A2 (LINEAR) a new observational phenomenon of cometary
outburst
activity has been discovered.
Key words: comets – CCD observations – astrometry – photometry.
Local
reference system
of
12 extragalactic radiosources used
for radio-optical connection
PETRE Popescu,
RADU Popescu, GHEORGHE
Bocsa, PETRE Paraschiv,
ALIN Nedelcu,
LIVIU Şerbanescu,
OCTAVIAN
Badescu
Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
petre@aira.astro.ro
Abstract.
Within the framework of the regional collaboration, we started a new
campaign
for CCD observations of the optical counterparts
of extragalactic radiosources
defining ICRF. The observations were performed between 10–17 October
2004 at
Belogradchik Observatory (Bulgaria)
using the 60 cm Cassegrain telescope
endowed with a 1k´1k Apogee 47P CCD
camera, leading to a
field of size 6.16' with scale of 0.722''/pixel
in 2´2 binned mode. The
astrometric reduction is done using three
high-density astrometric catalogs: USNO B1.0, 2MASS and UCAC2. The
first
results
are presented in this paper.
Key words: astrometry – reference systems.
SOFTWARE TECHNIQUES FOR ANALYZING CELESTIAL OBJECTS ON PHOTOGRAPHIC PLATES
Liviu ŞERBĂNESCU1, MIHAI CARAMIHAI2, Carmen TOMA2, Şerban GĂLOIU2, Alina ŞERBAN2
1 Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
livius@aira.astro.ro
2 “Politehnica”
University
Splaiul
Independenţei 515,
E-mail:
m.caramihai@ieee.org
Abstract. The
automatic detection from the catalog for the astronomical objects from
photographic plates (and implicit their identification)
is necessary for a
better use of the photographic plates library that exists at the
Astronomical
Institute of the
the astronomical objects
on the photographic plates we need information regarding relative
magnitude and
relative position on the plate, on the
one hand, and the stellar catalogue in
electronic format, on the other hand. To set up a reference system is
necessary
for the user to identify
precisely on the plate two objects from the catalogue.
During the taking over of the coordinates and magnitudes of the two
astronomical
objects is created a correspondence between the catalogue and the
database of the astronomical objects from the plate. In addition, it is
necessary to establish an admissible error for the objects
correspondence.
Implementation of SQL queries makes possible the finding of the
correspondence.
As result to the queries, we will get two tables: one containing the
identifier
of the astronomical object, its coordinates and
the magnitudes of the objects
from the plate that have been found in the catalogue, and the second
containing
the coordinates and the magnitudes
of the objects from the plate that have not
been found in the catalogue. It is possible to extend the
correspondence to
more stellar catalogues,
and so the list with unidentified objects is reduced
and the certainty for the identified objects in all catalogues
increase. In
this case, the
references system will be chosen starting from all catalogues
included in the software.
Key words: astrometry – stellar catalogues – photographic plates.
THE CATALOGUE
OF REFERENCE STARS
VLADIMIR RYLKOV, NATALIA NARIZHNAYA
Main
Astronomical Observatory of the
Pulkovskoe
Shosse 65/1, 196140 St.
Petersburg-140,
E-mail:
vryl@gao.spb.ru
Abstract. At Pulkovo the Pul GRS program of the
photographic
observations of stars around 116 Galactic Radio Sources (GRS) from
Hipparcos
Input Catalogue started with the Pulkovo Normal Astrograph in autumn
1994. Till
now the positions of more than 13000 stars
for 72 radio-star fields have been
obtained. The equatorial coordinates of 72 galactic radio-stars on
J2000.0 to
FK5 system are tabulated.
Key words: reference stars – compiled catalogue – galactic radio-stars