JOSÉ LUIS BALLESTER
Departamento
de Física,
Universitat de les Illes Balears
07122
E-mail: joseluis.ballester@uib.es
Abstract. The solar corona
is the outer layer of the solar atmosphere and is
structured by the coronal magnetic field.
During the last thirty years, space
missions have provided us with a lot of information about the physical
conditions and
structures of the solar corona, however, several important
phenomena still remain without explanation. Among them,
we could mention the
coronal heating problem, and the onset and development of coronal mass
ejections.
Key words: Sun – solar corona – active regions − magnetic field.
ASTRONET: PLANNING
FOR EUROPEAN ASTRONOMY
Birgitta Nordström
Niels
Bohr
Institute, Copenhagen University
Juliane
Maries Vej
30, DK-2100 Copenhagen, Denmark
E-mail:
Abstract. ASTRONET is a
European project financed by the European Commission for 4 years and
led by
Funding agencies
of several European countries. Its aim is to establish a
comprehensive, long-term planning process for all of European
stronomy – at
all wavelengths, from the ground and from space, and for all of
and the
planning for infrastructures is ongoing.
Key
words: European astronomy
– Science Vision – infrastructures.
CHEMICAL AND DYNAMICAL
EVOLUTION OF THE GALACTIC
DISK
Birgitta
Nordström
Copenhagen
University
Niels
Bohr Institute
Juliane
Maries Vej
30, DK-2100 Copenhagen, Denmark
E-mail:
Abstract. We consider the
Milky Way Galaxy a typical spiral galaxy. Stars
from its entire history are available for study.
Complete data for 14,000
long-lived stars allow us to study the chemical and dynamical evolution
of the
Galactic disk.
We find that there is a large scatter in metallicities at all
ages and that the velocity dispersion increases throughout the history
of the
Milky Way. These findings are challenges for the standard evolutionary
models
and more detailed models are needed.
Key
words: Galactic Disk – age determination
– age-metallicity relation – disk
heating.
JAN PALOUŠ
Astronomical Institute
Boční
II 1401, Praha 4
E-mail:
palous@ig.cas.cz
Abstract. The evolution of
galaxies results from a combination of internal
and external processes. The star formation is an
internal process transforming
cold and dense cores of molecular clouds to stars. It may be triggered
internally by expanding
shells, or externally, e.g., by galaxy collisions. The
gas accretion and galaxy merging events are external contributors to
galaxy
evolution. They compete with another internal process of galaxy
evolution,
which is the secular evolution redistributing the mass
and angular momentum
inside of galaxies as a consequence of bar and spiral arms formation.
As a
nearby example of gas
accretion we mention the interacting system Milky Way −
Large and Small Magellanic Clouds. Stripping of ISM in galaxy
clusters is
reviewed as another example of interaction of galaxies with their
environment.
Key words: ISM: structure − Stars: formation − Galaxies: evolution – Galaxies: star clusters – Galaxies: Magellanic Clouds – Galaxies: interactions -- Galaxies: clusters.
CHROMOSPHERICALLY ACTIVE SINGLE AND BINARY STARS − SPOTS: THE SOLAR-STELLAR CONNECTION
ELENI ROVITHIS-LIVANIOU
Department
of Astrophysics-Astronomy and
Mechanics, Faculty of Physics,
E-mail: elivan@phys.uoa.gr
Abstract. The active single as
well as binary stars are examined in this short review. In particular,
the
methods used to study their spot activity
from photometric and spectroscopic data are presented. The up-to-now
achieved
results are mentioned, and a comparison to the Sun is given, too.
Key words: active variable stars – active binary systems – sunspots – spots data analysis.
MAGNETIC SUPPORT OF PROMINENCES
BRIGITTE SCHMIEDER
Observatoire
de
Paris, Section Meudon LESIA,
92195
Meudon, France
E-mail:
brigitte.schmieder@obspm.fr
Abstract. Prominences are
intriguing to solar physicists since more than a
century. Many problems concern the support of the cold and
dense plasma of
prominences (104
K) embedded in the hundred times
diluted and hot
corona (106
K). I will review the different
possible
models
concerning such structures.
Key words: solar physics – Sun prominences – MHD.
JAN OLOF STENFLO
E-mail:
stenflo@astro.phys.ethz.ch
Abstract. Practically, all
variability in the Universe, on short or
intermediate time scales, is caused by magnetic fields. Dynamo
processes
in stellar
interiors generate magnetic fields that are brought up to the surface
by
buoyancy forces and emerge in the photosphere as bipolar
magnetic regions. The
large-scale bipolar regions on the Sun, which emerge at low
heliographic
latitudes, are what we normally call “solar
active regions” with sunspots,
faculae, and flares, above which a dynamic and complex system of closed
magnetic loops in the corona forms.
There is however a continuous scale
spectrum of bipolar regions, spanning from the large scales to the
smallest
scales that we can resolve.
While we can observe reasonably well how magnetic
flux emerges in the solar atmosphere, we know almost nothing about the
processes by
which flux is removed. The flux removal rate must balance the flux
emergence rate, otherwise the solar atmosphere would very quickly get
choked by
the accumulated magnetic fields, but we do not know how this is done.
This is a
central problem with implications for many areas
of contemporary astrophysics.
Key words: Sun – magnetic fields – dynamo processes.
STUDY
OF THE SEISMICALLY
ACTIVE FLARE OF JULY
16, 2004
DIANA BeŞliu-Ionescu
1, 2, ALINA-CĂTĂLINA
Donea 1, PAUL
S. CALLY 1,
CHARLES LINDSEY 3
1 Centre for Stellar and Planetary Astrophysics
School
of Mathematical Sciences,
Clayton
3800,
Australia
E-mail:
diana.ionescu@monash.edu.au,
alina.donea@sci.monash.edu.au,
paul.cally@sci.monash.edu.au
2 Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557, Bucharest, Romania
E-mail:
deanna@aira.astro.ro
3
NorthWest Research Associates, Inc.
E-mail: lindsey@sprc.com
Abstract. Sunquakes
have proven to be the most powerful events occurring at the solar
surface. They
are triggered by the impulsive
flares produced in the corona, just above the
acoustically active regions. Not every impulsive flare produces seismic
waves
emanating
from the highly depressed photosphere, just beneath the flare.
So far, we have identified a few
mechanisms which can deliver acoustic energy into the photosphere: (1)
the back-warming
radiation
suddenly heating the photosphere; (2) a strong shock-like compression
wave propagating downwards into the chromosphere; (3) relativistic
particles
delivering directly the energy and momentum into the photosphere; (4)
probably
the magnetic tension at the feet of the loops.
In order to discriminate which of
these is the most efficient or dominated during a particular
acoustically
active flare, we have analyzed
the coronal and chromospheric emission of the
regions just above the seismic source. We have performed a
multiwavelength
analysis of the
active region 10649 that hosted the acoustically active solar
flare of
layers of the Sun, from the
photosphere to the corona, suggests that high-energy particles travel
through
the coronal layers from the reconnection
site, hit the solar chromosphere
warming it up, which then, responds by sending further into the
photosphere
sufficient energy (carried either by
the shock wave or by the Balmer and
Paschen radiation) to produce a seismic event.
Key words: solar flares – sunquakes – Hα observations.
FLUORESCENCE
OF THE ATMOSPHERE
AND
COSMIC RAYS. EXPERIMENTAL
DATA
OF
THE “UNIVERSITETSKY-TATIANA” SATELLITE
GALI GARIPOV,
BORIS KHRENOV,
PAVEL
KLIMOV
D. V.
Skobeltsyn Institute of Nuclear Physics
of
Leninskie
Gory 1, 119992
E-mail:
pavel.klimov@gmail.com
Abstract. Detector on board
the
radiation from January 2005 to March 2007. The data on various kind of
UV-radiation (scattered moonlight, aurora lights, and transient
luminous
events) are presented. They are discussed in the context of future
observation
by space-based detectors of UV fluorescence
tracks produced in the atmosphere
by ultra-high energy cosmic rays.
Key words: night atmospheric UV radiation – transient luminous events – ultra-high energy cosmic rays.
ENVIRONMENTAL EFFECTS ON GALAXIES IN CLUSTERS
PAVEL Jáchym
Astronomical
Institute of the
Boční II 1401,
E-mail:
jachym@ig.cas.cz
Abstract. Using the
N-body/SPH code GADGET adapted for interactions of two
gaseous phases, we study the influence of ram
pressure stripping on spiral
galaxies in galaxy clusters. Galaxies on highly radial trajectories
cross in
the cluster center the density peak
of the intracluster medium (ICM) and
experiences a time-varying wind. Density of the ICM and orbital
velocity of the
galaxy determine
effects of the ram pressure. Depending on the duration and
intensity of the interaction, different amounts of interstellar
material (ISM)
are found to be stripped from galaxies. The presence of the ISM in the
galaxies
is crucial for their star formation activity.
Key words: galaxy clusters – galaxy interaction – interstellar material.
ASTROMETRIC
SOLAR OBSERVATIONS FROM
TATJANA JAKŠIĆ 1, MIODRAG DAČIĆ 2, ISTVAN VINCE 2
1 University
of
Studentski
Trg 16, 11000
2 Astronomical
Observatory of
Volgina
7,
11160 Belgrade, Serbia
E-mail:
ivince@aob.bg.ac.yu
Abstract. From 1974
up to 1994, observations of stars, and Sun, Mercury and Venus, were
performed in
daylight with the
of the Astronomical Observatory of
Belgrade. The principal goal of these observations was to correct the
positions
of the vernal equinox
point and of the celestial equator plane. Numerous
observations of upper and lower, as well as right and left Solar disk
edges,
enabled the
determination of the solar diameter variations as function of time.
This allowed the investigation of the correlation of the considered
variations
with the cycle of solar activity.
Key words: astrometry – vernal equinox – equator plane − solar diameter variations.
SOLAR
ACTIVITY INFLUENCE
ON
BRIGHTNESS CHANGES
OF
THE PERIODIC COMETS
29P/SCHWASSMANN-WACHMANN AND
1P/HALLEY
Famil
Mustafa, Ayyub
Guliyev,
Elchin Babayev,
Peter
Shustarev
Shamakhy
Astrophysical Observatory named after
N. Tusi
10,
Istiglaliyyat Street, AZ-1001,
E-mail:
ebabayev@yahoo.com
Abstract. The
influence of solar activity on changes of brightness of two
periodic comets (29P/Schwassmann-Wachmann and 1P/Halley)
is investigated. The
brightness changes of 1P/Halley were studied on the basis of about 5900
estimations of brightness data obtained along
the period 1981−1989 and covering
distances from 0.6 AU up to 9 AU. The brightness curve of
29P/Schwassmann-Wachmann was a
result of about 1300 estimations for the period
1976−2005. Spectral, correlation and cross-correlation analyses of both
variations in solar
activity (different mechanisms) and changes of brightness
of the investigated comets showed a presence of similar changes for the
same
considered time span. Some well-known periodicities in solar activity
variations were also revealed in periodical changes of comet
brightness.
It is
concluded that interrelations between solar activity variations and
brightness
changes of studied comets are significant. The telescope
apertures are also to
be considered in calculations.
Key words: solar activity – periodic comets – brightness changes – telescope aperture.
STRUCTURE
AND SHAPE OF
THE SOLAR CORONA
DURING
THE TOTAL SOLAR
ECLIPSE
OF
MYKOLA PISHKALO, IEVGENIIA SADOVENKO
Faculty of Physics, Department of Astronomy and Space Physics
2,
Glushkove ave., Kyiv-127,
E-mail: pish@observ.univ.kiev.ua
Abstract. Structure
and shape
of the solar corona during the total solar eclipse of
March 29, 2006
determined. The flattening index e = a + b was
found
to be about 0.17. Main coronal
structural
features were found to be northern
and southern polar ray systems over polar
coronal holes and six streamers of different brightness, located in middle and low heliographic
latitudes. Detailed
coronal structure was analyzed. It was found that all coronal
structural
features had their counterparts on
photosphere-chromosphere level, at the limb
or near it.
Key words: Sun – solar corona – structure –
flattening
index.
ADRIAN
SABIN POPESCU
Astronomical
Institute of the
Str.
Cuţitul de
Argint 5, 040557 Bucharest, Romania
E-mail:
sabinp@aira.astro.ro
Abstract. We
interpret the D.E.U.S. (Dimension
Embedded in Unified Symmetry) objects embedded in the catenoid of a
higher
D.E.U.S.
object as Stephani Universes. In this assumption, we check for the
validity of
the Gibbs-Duhem equation, one of the four
conditions needed in order that the
fluid to evolve in local thermal equilibrium.
Key words: spacetime topology − multiverse − thermodynamic processes.
Interplanetary magnetic field asymmetry near Earth’S orbit
Volodymyr Reshetnyk
Astronomy
and Space Physics Department
Av.
Glushkova 2,
E-mail:
vmr@univ.kiev.ua
Abstract. The interplanetary
magnetic field (IMF) is strongly related to very various phenomena of
the solar
wind. The direction and
magnitude of IMF change continuously and significantly.
In this paper we investigate the long-time variation of magnitude and
direction
of the IMF vector. The IMF near the Earth was studied using the
National Space
Science Data Center OMNI database. We obtained
an asymmetry in the distribution
of the IMF direction: the northern field is stronger than the southern
one. We
also analyze IMF distribution
during the different phases of the solar cycle
and solar wind parameters.
Key words: interplanetary magnetic field – solar wind − heliosphere.
LOW-LATITUDE
BOUNDARY LAYER
(LLBL): STRUCTURE, DYNAMICS,
AND MAGNETOSHEATH PLASMA
PENETRATION
INSIDE THE MAGNETOSPHERE
svetlana
rOSSOLENKO1,2,
Elizaveta ANTONOVA1,2, YUri
YERMOLAEV2, Igor KIRPICHEV2, Mikhail
VERIGIN2, Natalia BORODKOVA2, Elena
BUDNIK3
1 Skobeltsyn
Institute of Nuclear
2
3
Centre d’Études et des
Recherches des Rayonnements, Toulouse, France
Abstract. The
mixing of magnetosheath and plasma sheet plasma in LLBL is studied on
the base
of INTERBALL/Tail probe observations.
Variations of the fluxes of ions and
electrons and the magnetic field are analyzed. The thickness of LLBL
for a
number of cases is evaluated.
The dependence of LLBL thickness on the changes of
solar wind magnetic field and velocity is investigated. The connection
between
the solar
wind magnetic field direction and the turbulent fluctuations of
magnetosheath magnetic field is analyzed. The influence of
magnetosheath
magnetic
field fluctuations on the magnetopause stress balance is discussed. It
is shown that one of the main factors determining the formation and
structure
of LLBL is the turbulent nature of magnetic field and plasma
fluctuations in
the magnetosheath.
Key words: low latitude boundary layer – magnetosheath – turbulent fluctuations.
MUTUAL PHENOMENA OF URANUS’ SATELLITES: FUTURE ROMANIAN PHOTOMETRIC OBSERVATIONS
Ştefan Gabriel Sorescu 1, 2
1Astronomical
Institute of the
Astronomical
Observatory
Str.
Cuţitul de Argint 5, 040557
2“Mircea
cel Bătrân”
Str.
Fulgerului 1, 900218,
E-mail:
sorescu@aira.astro.ro
Abstract. We present a
short history of mutual phenomena campaigns in
The tests we have made for this
campaign, the main problems in observing the satellites, and the list
of selected
phenomena are also described.
Key words: Uranus’ satellites – photometry.
DANA VICAŞ
Astronomical
Institute of the
Astronomical
Observatory Cluj-Napoca
Str.
Cireşilor
19, 400487 Cluj-Napoca, Romania
E-mail:
dana.vicas@gmail.com
Abstract. A study of the
galaxy IC 51 is proposed, aiming to confirm whether
IC 51 is a polar ring galaxy or not, and to provide
more information on the
dynamics of interactions between galaxies.
Key words: extragalactic astronomy – polar ring galaxy – neutral hydrogen – radio interferometry.