THE LAST TOTAL SOLAR ECLIPSE OF THE MILLENNIUM IN TURKEY
Dedicated to the Memory of Prof.
Dr. M. Dizer
(1924 - 1993)
Istanbul, Turkey, August 13 - 15, 1999
Contents
Local Organising Committee
Scientific Organising Committee
List of Sponsors
Preface
Conference Program
Invited Talks
Oral Contributions (in order of presentation)
Posters
List of Participants
LOCAL ORGANIZING COMMITTEE
SCIENTIFIC ORGANIZING COMMITTEE
Bogazici University
Scientific and Technical Research Counsil
of Turkey
Magister Tours Inc.
Preface
So many topics, so little time. That is
one reaction to what we witness
here at this symposium with the convergence
of traditional ground-based
eclipse and coronagraph archives with
the new input from space. In this
century there has been an accumulated
4 hours of totality. Recall that
the inspiration for the discovery of cosmic
magnetism came directly from
white light eclipse photographs of the
solar corona. Papers and posters
on that subject are given by Espenak,
Karovska, Mikic, Minarovjech,
Russin, and Takeda. (Pardon if we list
only the lead authors here).
Polarimetry in all its forms and all its
power are represented by
Bougaenko, Faurobert, Kulijanishvili,
and Stenflo. Observations based
on spectra or monochromatic filters are
described by Chiuderi, Hiei,
Khetsuriani, Kim, Makita, and Minarovjech.
The question of cool material
is addressed by Dermendjiev. The theory
of wave heating falls to Chiuderi
and Ofman. The exciting new view from
space is taken up by Akiyama, Khan,
Poland, Spergel, and Yashiro. Some solar-terrestrial
effects here in
Turkey are described by ?Caglar. Finally,
and most important these days
are public educational activities as reported
by Pike.
This was the program to mid-June. There
may be additions and deletions.
Symposium Programme
Friday, August 13
09:00 Opening of the registration desk
09:40 welcome address
Morning Session Chair: I. Kim, Moscow
10:00 Rusin,SHAPE AND STRUCTURE OF THE
WHITE-LIGHT CORONA OVER SOLAR CYCLES
11:00 Hiei,Results of the observations
of the total solar eclipses of 1994,
1995, 1997, and 1998.
11:20 Coffee Break
11:50 Livingston,SOLAR ECLIPSE RESULTS
FROM THE 4 HOURS CUMULATIVE
12:50 Ichimoto,Observations of the coronal
oscillations and waves
13:10 Lunch
Afternoon Session Chair: A. I. Poland, NASA
14:30 Espenak,DIGITAL COMPOSITING TECHNIQUES
FOR CORONAL IMAGING
15:30 Minarovjech,Comparison between the
white-light and emission corona
15:50 Coffee Break
16:20 Ofman,Dissipation of slow magnetosonic
waves in coronal plumes
16:40 Khan,Sudden disappearances of transequatorial
X-ray loops
17:00 Cacciani, Precise polarimetry of
the corona and solar disk magnetic fields measured with a compact
version of the MOF.
Saturday, August 14
Morning Session Chair: E. Hiei, Tokyo
09:30 Stenflo,WHAT CAN WE LEARN FROM POLARISATION
MEASUREMENTS?
10:30 Faurobert,Hanle effect of weak solar
magnetic fields
10:50 Coffee Break
11:20 Bougaenko,Eclipse polarimetric observations
of prominences
11:40 Kulijanishvili,Electropolarimetry
of the solar corona
12:00 Poland,CORONAL OBSERVATIONS FROM
SPACE: SKYLAB THROUGHOUT SOHO
13:00 Lunch
Afternoon Session Chair: V. N. Dermendjiev, Bulgaria
14:30 Poster session
15:30 Coffee Break
16:00 Poster session
Sunday, August 15
Morning Session Chair: J. O. Stenflo, Zurich
09:30 Dermendjiev, THE PROBLEM OF
THE COOL MATTER IN THE SOLAR CORONA
10:30 Mikic, MHD modelling of the solar
corona
10:50 Coffee Break
11:20 Gigolashvili, On the investigation
of active prominence and emission lines of surrounding
corona
11:40 Kim, ECLIPSE SPECTRA OF CORONAL
VELOCITY FIELD
12:40 Closing address
Invited Talks
Shape and structure of the white-light
corona over solar cycles
V. Rusin
Astronomical Institute, Slovak Academy
of Sciences, Tatranska Lomnica, Slovakia
White-light streamers seen during total
solar eclipses are the most
remarkable phenomena in the solar corona.
Their brightness, shape and
location above the solar surface show
different images at different
phases of the solar cycle. This behaviour
of the corona 'image' is
determined by major differences in magnetic
flux properties during
a solar cycle. In the present paper we
will deal with a shape of the
white-light corona (flattening index),
integral brightness and a
location of coronal streamers around the
solar limb as observed during
solar eclipses. Possible scenario of the
distribution of coronal
streamers and its development over cycle
will be discussed.
Solar eclipse results from the 4 hours
cumulative
W. Livingston
National Solar Observatory, Tucson,
USA
Over the past century there have been 69
total eclipses with an average
duration of 3.5 minutes. We review the
significant advances achieved by
eclipse experiments. Early white-light
coronal photographs suggested
structures that must have been dominated
by magnetic fields. This led
to the discovery of surface magnetism
in sunspots by Hale (1908).
Delicate direct photographic observations
confirmed, from the bending
of starlight near the Sun, Einstein's
General Theory of Relativity (1919).
Chromospheric flash spectra indicated
that the outer atmosphere of the
Sun was much hotter than the underlying
photosphere. This led to non-local
thermodynamic equilibrium concepts and
the idea of various mechanical and
wave processes to maintain it. Decades
have been devoted to understanding
the corona. Discovery of its million degree
plus temperature, figuring
how to heat it, enquires into whether
it co-rotates with the Sun, its
dissolution into the solar wind, how cool
prominences co-exist within it,
all are topics to which eclipse observations
have contributed.
Digital compositing techniques for coronal
imaging
F. Espenak
NASA/GSFC, Greenbelt, Maryland 20771
USA
The solar corona exhibits a huge range
in brightness which cannot be
captured in any single photographic exposure.
Short exposures show the
bright inner corona and prominences, while
long exposures reveal faint
details in equatorial streamers and polar
brushes. For many years,
radial gradient filters and other analog
techniques have been used to
compress the corona's dynamic range in
order to study its morphology.
Such techniques demand perfect pointing
and tracking during the eclipse,
and can be difficult to calibrate.
In the past decade, the speed, memory
and hard disk capacity of personal
computers have rapidly increased as prices
continue to drop. It is now
possible to perform sophisticated image
processing of eclipse photographs
on commercially available CPU's. Software
programs such as Adobe Photoshop
permit combining multiple eclipse photographs
into a composite image which
compresses the corona's dynamic range
and can reveal subtle features and
structures.
Algorithms and digital techniques used
for processing 1998 eclipse
photographs will be discussed which are
equally applicable to the recent
eclipse of 1999 August 11.
What can we learn from polarisation
measurements?
J. O. Stenflo
Institute of Astronomy, ETH-Zentrum,
Zurich, Switzerland
Coronal physics has profited from polarisation
measurements in a variety
of ways: Broad-band polarimeter of the
K corona has provided information
on the geometry of coronal streamers,
observations of scattering
polarisation in coronal forbidden lines
have given us information on the
direction of the coronal magnetic field,
radio observations have placed
constraints on the strength and configuration
of the magnetic field above
active regions, and photospheric magnetograms
have been used as boundary
conditions for extrapolations of coronal
magnetic fields. Still we lack
suitable tools for direct measurements
of field strengths in the corona.
Future possibilities include observations
of the longitudinal Zeeman
effect in infrared forbidden lines with
large-aperture coronagraphs,
and observations of the Hanle effect in
X-ray resonance lines.
For the chromosphere-corona transition
region we need to observe
the Zeeman and Hanle effects in resonance
lines in the solar EUV to
diagnose the strength and direction of
the magnetic field.
In the visible, Zeeman and Hanle observations
in strong lines allow
access to the canopy magnetic fields in
the lower chromosphere.
Observations of impact polarisation and
the Stark effect due to
macroscopic magnetic fields offer additional
diagnostic possibilities.
Coronal observations from space: skylab
throughout SOHO
A. I. Poland
NASA/GSFC, Greenbelt, USA
The Skylab White Light Coronagraph provided
us with our first clear
space based observations of the solar
corona (there were earlier space
coronagraphs but the detector technology
did not yet provide clear images).
The Skylab coronagraph had the advantage
of using photographic film that
was returned from space by the astronauts.
The P78 Navy coronagraph
provided our first electronic images of
the full corona.
This, combined with difference imaging
provides impressive views of
coronal dynamics.These were followed by
the SMM coronagraph that
operated between approximately 1.5 and
9Ro. It provided higher spatial
resolution at the expense of 360-degree
images. The most recent SOHO
coronagraph provides rather spectacular
images using 3 coronagraphs
that image from very close to the Sun's
surface to 30Ro.
The primary advantage of ground based
observations is the ability to get
very high-resolution images of the corona
very close to the Sun.
The complementary advantage of space observations
is the ability to get
many images, fairly frequently, over an
extended period of time.
These frequent observations have allowed
us to get reliable measurements
of the average background corona and have
allowed us to follow the
rotation and evolution of streamers. In
this talk I will compare images
from the various space coronagraphs and
present movies of coronal
dynamics from the SOHO spacecraft.
The problem of the cool matter in the
solar corona
V. N. Dermendjiev
Institute of Astronomy, Bulgarian Academy
of Sciences, Sofia, Bulgaria
There are sporadic reports of eclipse observers
claiming for registration
of low excitation, chromosphere or prominences
like, emission in the solar
corona. Whether such an emission belong
to the ions or excited hydrogen
atoms of real transitory, short living
coronal phenomena, extremely
difficult for registration. Are there
theoretical arguments in support of
such hypothesis? What is the role of the
solar mass ejections,
the filament channels and the recently
discovered relatively small-scale
plasmoid structures in the corona? In
this review talk we give first,
in short, the history of the problem and
then continue with an attempt
to show possible motivations for extension
of the problem on the base of
some contemporary theoretical conceptions
and observational results.
Eclipse spectra of coronal velocity
field
I. S. Kim
Sternberg State Astronomical Institute
of Moscow State University, Moscow, Russia
As a rule, totality sky brightness is significantly
reduced resulting in
imitation of space-borne conditions. This
allows to record spectra of the
E-corona (emission line corona) in the
range 1.5-3 R which seems to be
the most interesting in sense of searching
the regions of the solar wind
acceleration. An instant multi-slit emission
line spectrum can provide
the information about thermal, non-thermal,
and Doppler velocities as
well as coronal rotation. Comparative
analysis of grating and Fabry-Perot
eclipse observations made by different
authors is given. Reliability of
grating observations followed by reference
spectra is noted.
Concordance of parameters of feeding optics
and Fabry-Perot interferometer
as well as simultaneous exposures of a
reference spectrum and coronal
one is required to get unambiguous interpretation
of coronal interferograms.
Summary of reduction of former eclipse
"green" line (Fe XIV 5303 ?)
Fabry-Perot interferograms revealing fringes
at distances of 1.1-2 R
is presented for the line width, Doppler
shifts and coronal rotation.
Reliable profiles corrected for the input
of the white-light corona and
instrumental effects were used. Averages
FWHM of 0.8 ?, 0.9 ?, and 1.0 ?
are found for streamers above active regions,
helmets, and hole respectively.
95 % of profiles have Doppler shifts <
20-km. s-1. Doppler shifts > 40-km.
s-1 are not detected. Prospects for direct
coronal rotation researches
based on space-borne or eclipse Fabry-Perot
interferograms followed
by reference spectra is discussed.
Oral Contributions ( in order of
presentation )
Results of the observations of the total
solar eclipses of 1994, 1995, 1997, and 1998.
E. Hiei and the Eclipse Group of Meisei
University
Hodokubo, Hino, Tokyo, Japan
The eclipse group of Meisei University
observed successfully the corona
at the solar eclipses of Paraguay on 3
November 1994, East India on 24
October 1995, Siberia on 9 March 1997,
and Guadeloupe on 26 February 1998.
All of them show clearly the polar plumes,
and their widths and electron
density distribution are reported.
Observations of the coronal oscillations
and waves
K. Ichimoto
National Astronomical Observatory of
Japan, Tokyo, Japan
At the Norikura Solar Observatory, we have
been observing time variations
of intensity and Doppler shift of coronal
emission lines with spectroscopic
and filtergraphic methods. Periodic variations
are frequently found in
the Doppler signal but not in the intensity
signal in active region
corona. Typical amplitude is 0.5-1.0 km/s
with the period of 3-40 min.
Since there is no significant variation
in intensity or intensity ratio
associated with the Doppler signal, the
observations seem to suggest
the incompressive nature of the coronal
wave. Movies of 2-dimensional
Doppler images give us a hint of disturbances
propagating upward in the
corona.
In the presentation, we also like to introduce
the new green-line imaging
system at the Norikura Solar Observatory.
Comparison between the white-light and
emission coronae
M. Minarovjech
Astronomical Institute, Slovak Academy
of Sciences, Tatranska Lomnica, Slovakia
We present a comparison between the white-light
and emission coronae as
obtained during solar eclipses, the white-light
K-coronameter MARK 3
images and patrol observations in the
530.3 nm line (the green corona).
This brightness comparison has been done
for different phases of the solar
cycle activity. It was found a strong
dependence between areas of maximum
intensity of the white-light and green
emission coronae. Possible mechanism
of such behaviour will be discussed.
Dissipation of slow magnetosonic waves
in coronal plumes
L. Ofman
NASA Goddard Space Flight Centre, Greenbelt,
USA
Recently, slow magnetosonic waves were
identified in polar plumes at
heights up to bout 1.2Rs, using Extreme
ultraviolet Imaging Telescope (EIT)
observations of quasi- periodic EUV intensity
fluctuations. We model
the propagation and dissipation of slow
magnetosonic waves in polar coronal
plumes using 2D MHD code in spherical
geometry. We find that outward
propagating slow magnetosonic waves may
become trapped due to transverse
density and temperature structure of the
plumes.
The slow waves nonlinearly steepen in
the gravitationally stratified plumes.
The nonlinear steepening of the waves
leads to enhanced acceleration of
the subsonic solar wind due to momentum
transfer, and to the enhances
dissipation due to compressive viscosity
at the wave-fronts.
The slow waves can contribute to the heating
of coronal holes close to
the Sun (r<2Rs); a region where the
shear Alfven wave heating is
inefficient.
Hanle effect of weak solar magnetic
fields
M. Faurobert
Observatoire de la Cote d'Azur, Nice,
France
The Hanle effect provides a diagnostic
tool for weak magnetic fields,
which do not give rise to a measurable
Zeeman effect, such as turbulent
fields or magnetic canopies. The lines,
which are sensitive to the Hanle
effect, are formed under non-LTE conditions
by scattering of photons.
After a brief description of the physical
mechanism at hand, I will show
on some examples, how this effect may
be used for the diagnostics of weak
magnetic fields in quiet regions of the
solar photosphere or chromosphere.
Electropolarimetry of the solar corona
V. Kulijanishvili1,
J. Lominadze1, M. T. Ozkan2,
A. Okten2
1 Abastumani Astrophysical Observatory,Tbilisi,Georgia
2 Istanbul University Observatory,
Istanbul, Turkey
The results of the white-light polarisation
measurements performed
during the solar eclipse of November 3,
1994 are presented.
An electropolarimeter of original design
controlled by PC had been
constructed. It allows scanning the solar
corona during the full phase
of solar eclipse over 10 concentric rings
up to 4 solar radii.
In each ring measurements of the total
radiation of the solar corona
were made at 90 positions with subsequent
calculation of polarisation
degree and direction of plane of polarisation.
In this way measurements
of polarisation degree in the inner and
outer corona have been carried
out.
The assumption of an isothermal corona
with a hydrostatic distribution of
density is used to calculate the polarised
components, ln (Kt¤Kr).
The comparison of the observed data with
the theoretical curves has
shown that density distribution at distances
r<(1.2-2.5)RŲ fits the
applied corona model.
It was obtained that the temperature in
the middle corona in the
equatorial zones is constant and equals
to 1.53x106K and the density
(the parameter of hydrostatic law) varies
from 8.2x108cm-3 (East coronal
streamer) to 4.2x108cm-3 (West coronal
streamer).
Eclipse polarimetric observations of
prominences
O.I. Bougaenko1,
I.V. Alexeeva1, A. A. Belinski2,
M. I. Divlekeev1,
I. S. Kim1,
G. A. Miagkov3, Y. D. Park4,
V. V. Popov1 and D. A. Seleznev2
1 Sternberg State Astronomical Institute
of Moscow State University,Moscow,Russia
2 Astronomical Department of Physics
Faculty of Moscow State University,Moscow,Russia
3 Russian State University of Humanities,
Moscow, Russia
4 Korea Astronomy Observatory, Yusong-gu
WWTaejon, Korea
Non-filter eclipse polarimetric observations
of H( -prominences made in
1994 by a chronograph-polarimeter are
discussed. A rotating polariser
synchronised with a professional motion-picture
camera and a colour
negative film was used. Digitising through
a red wide band filter was made
for 24 frames corresponding to one rotation
of a polariser. IDL software
and Stokes-vector presentation applied
to the digitised images resulted
in accuracy of 2% for polarisation degree
and 2( for polarisation
direction.It's concluded that filter prominence
observations would
improve accuracy to less than 1 % and
1( for polarisation degree and
direction respectively. Prospects for
the forthcoming eclipse magnetic
researches of prominences are noted.
Sudden disappearances of transequatorial
X-ray loops
J. I. Khan1
and H. S. Hudson2
1 Mullard Space Science Lab., University
College London, UK
2 Institute of Space & Astronautical
Science, Sagamihara, Kanagawa, Japan
In late April 1998 to early May 1998 Yohkoh
Soft X-ray Telescope data
revealed large-scale soft X-ray loops
interconnecting NOAA active
regions 8210 and 8214. During the passage
of these active regions across
the solar disk we observed a remarkable
series of sudden disappearances
of these transequatorial loops. Each disappearance
led quickly to an
apparent `re-formation' of the structure.
Each of the disappearances was closely
associated with a major solar flare
in one of the active regions, and a coronal
mass ejection. Moreover,
these events were homologous in the sense
that the disappearing
structures strongly resembled each other
in form and location prior
to the disappearance, as well as in timing
relative to the flare. The
results indicate that the disappearances
of the transequatorial loops
are caused directly by the flaring.
The repeated `re-formation` of the transequatorial
loops suggests that rapid
reconnection of the coronal magnetic field
following each CME is the
origin of these structures, and moreover,
demonstrates the persistence of
the large-scale coronal magnetic field
in the presence of temporary but
large-scale restructuring.
Precise polarimetry of the solar corona
and disk magnetic field measurements, before and during the eclipse, using
a compact version of the MOF .
A. Cacciani and the Rome team
Univ.LA SAPIENZA, Physics, Rome, Italy
The MOF (Magneto-Optical Filter) is a powerful
instrument for Doppler and magnetic measurements on the solar photosphere.
It has been developed over the years by the first author of this contribution
and
is now in use at several Observatories (HAO, Mt Wilson, Crimea AO, IAC,
several places in Italy and Kanzelhohe in Austria). Soon it will be installed
at the University of Tashkent in Uzbekistan and possibly at the University
of Amman and Kandilli Observatory. Because of its compactness it is also
being considered for space missions. The best performances are being obtained
in collaboration with the Kanzelhohe Observatory (see please www.solobskh.ac.at).
This presentation includes its working principle, selected past results
and its application during the 11 Aug eclipse in collaboration with Dr
Atila Ozguc of Kandilli Obs. We will try to get the V Stokes parameter
on the wings of the Potassium line @ 770 nm. and the U,Q Stokes parameters
on the coronal white light during the totality.
MHD modelling of the solar corona
Z. Mikic, J. A. Linker, R. Lionello,
A. Tarditi, and P. Riley
SAIC, San Diego, California, U.S.A.
We will describe a three-dimensional MHD
model of the solar corona that
includes the self-consistent interaction
of magnetic, plasma, and gravity
forces, including the effect of the solar
wind. This model makes it
possible to determine the large-scale
structure of the magnetic field
in the corona, as well as the distribution
of the solar wind velocity,
plasma density, and temperature. We will
describe the application of our
model to the prediction of the structure
of the corona during the total
solar eclipse of August 11, 1999.
On the investigation of active prominence
and emission lines of surrounding corona
M. Sh. Gigolashvili, Ts. S. Khetsuriani
and E. I. Tetruashvili
Abastumani Astrophysical Observatory,
Tbilisi, Georgia
The variations of active prominence and
surrounding corona were observed
with the chromospheric telescope and Lyot
type chronograph of Abastumani
Astrophysical Observatory at October 10,
1978. The observations have been
performed in different spectral regions
and at various distances from the
solar disk. The radial velocities of different
fragments of the prominence
were measured in various lines. By the
continuum emission accompanying
bright knots, the prominence density was
estimated. The degree of linear
polarisation of the prominence continuum,
HeI D3 and green coronal lines
was measured. The polarisation of continuum
radiation turned out to be
smaller (4%), then predicted by the theory.
The degrees of polarisation
were measured for the six bright knots
of HeI D3. It turned out to be
about "0" in every knots except one situated
between two basic knots of
prominence, where it is about equal to
the permissible maximal value of
polarisation degree predicted by the theory.
These results seem to be
consequence of depolarising action of
nonradial magnetic fields.
The Polarisation degree for green line
was measured in the places,
corresponding prominence bright knot observed
in Ha, and hereabout of it
on both sides. The results of these measurements
were the same in all
cases.
The distribution of the green and red
coronal line intensities and half
widths with position angles and highs
above the solar disk are plotted.
We notice the variations of some coronal
formations with changes of
active prominence.
Posters (in order of alphabetical)
1. Akiyama, S. & Hara, H.: The occurrence probability of x-ray plasma ejections by solar flares
2. Caglar,I.& Eryildiz, C.: Monitoring of the telluric currents origined by atmospheric events in Boyali, northwestern Turkey
3.Chiuderi, C. & Califano, F.: Wave heating of nonuniform plasmas
4.Drago Chiuderi, F. et al.: EUV and radio observations of an equatorial coronal hole: a model of the upper transition region and corona
5.Gigolashvili, M. Sh. et al.: On the purposes of Georgian-Turkey joint group at solar eclipse in Elazig
6.Kandemir, G. & Boydag, S.: Solar variation of cosmic ray intensity
7.Karovska, M.& Zaccheo, T.S.: Estimating the characteristic size of the fine coronal structure
8.Makita, M.: Eclipse curves of CaII H K structures
9.Nagai, T. et al.: Internet relaying of total solar eclipse on August 11, 1999
10.Park, Y. D. et al.: Quantitative colour photometry of the solar corona
11.Pike, C. D. et al.: Sunblock '99 - an educational resource
12.Spergel, M. S.: Solar induced extrasolar nuclear reactions
13.Takahashi, N. et al.: Large-scale distribution of coronal temperature observed at the total solar eclipse on 26 February 1998
14.Takeda, A. et al.: Density structure of the coronal loops derived from the1991 total eclipse observation
15.Yashiro, S. & Shibata, K.:
Study of an emerging flux region observed with TRACE
The occurrence probability of x-ray
plasma ejections by solar flares
S. Akiyama and H. Hara
National Astronomical Observatory of
Japan, Kanagawa, Japan
Solar flares observed by Yohkoh soft X-ray
telescope occasionally show
loop-like or blob-like ejecta even from
relatively short duration events.
Shibata et al. (1995) found that all flares
(8 events) were associated
with X-ray plasma ejections above the
soft X-ray loop. They emphasised
that X-ray plasma ejections associated
with flares are a sign that flares
are the result of magnetic reconnection.
On the other hand, we empirically
know that some flares do not show any
ejection at all in SXT images.
We searched flares that occurred in 1996
(solar minimum), because we
can easily find faint plasma ejections
for low background emission. The
selection is based on the criterion that
SXT started observing the flare
well before the GOES peak. As a result,
we found 57 X-ray ejections (37 %)
out of 140 flares. We also examined the
Solar Geophysical Data for
Ha ejections, and there were 53 observation
reports out of our 140 events.
We found 32 Ha filament eruptions out
of 53 observation reports.
Finally we found 40 eruptive events (75
%) out of 53 flares by X-ray
or Ha observation. We concluded that many
flares have plasma ejections
and plasma ejection is one of important
phenomena for understanding
of flare mechanism.
Monitoring of the telluric currents
origined by atmospheric events in
Boyali, northwestern Turkey
I.Caglar, C. Eryildiz
Istanbul Technical University, Faculty
of Mines, Dept. Geophysics,
Istanbul,Turkey
Telluric currents have a number of origins
caused by naturel events such
as activities electrochemistry, atmospheric
electricity, ionospheric
conditions, solar activity and geomagnetism.
It is long since they
therefore are known to be closely related
to terrestrial and
extra-terrestrial phenomena. Only the
alternating electromagnetic field
of the earth that has a regional nature
and is intimately related to the
phenomena on the sun and in the ionosphere
is considered. The
electromagnetic field apparently arises
as a result of current systems
set up mechanically in the ionosphere.
These electromagnetic waves are
noted at the earth's surface as variations
in the geomagnetic field and
the telluric current field. The electric
part of such a field is known
as the telluric current field. Telluric
currents circulate continuously
in the upper regions of the earth's crust.
Between 21 and 27 August 1991,
ground based observations of the telluric
currents were made at Boyali,
Kastamonu (Northwestern Turkey).
The Boyali area is locatedat 41.3o N,
34.15oE, on the region of Cangal
metaophiolite geological
units. The station is located on the area,
with the lowest noise level.
A telluric monitoring station using an
electric dipole of 100-m length
with north-south direction is constructed
in the area. Two grounded
electrodes (Cu-CuSO4 non-polarizing type)
are used for the electric
dipole. During the continuous monitoring,
the telluric and the other
currents is simultaneously recorded on
a paper, moved at a rate of 1 cm
per minute. It is readily apparent that
the persistent variations and
the micropulsations have different patterns
caused by high atmospheric
electricity due to local lightnings, and
by geomagnetic field of the
earth. Unfortunately, small effects origined
by the artificial currents
and the noises due to the winds are observed
on the tellurograms. The
additional examples from different sites
recorded using a magnetotelluric
measuring system, are represented to show
more clear telluric variations
for some Pc geomagnetic pulsation frequency
range.
Wave heating of nonuniform plasmas
C. Chiuderi1
and F. Califano2
1 Dept. of Astronomy, University of
Florence, Italy
2 Instituto Nazionale Fisica della
Materia, Sez. A,Universit di Pisa, Italy
The dissipation of Alfven waves in a nonuniform
plasma is investigated
in two different scenarios describing
the dynamics of an energetically
isolated system and that of an externally
driven system. It is argued that
the second one could indeed mimic the
coronal situation and it is shown a
direct numerical evidence that the dissipation
of the waves takes place
at a rate that is independent of the value
of the electrical resistivity.
This proves the validity of a conjecture
put forward long ago, at least in
the framework of 2-D MHD. It is also shown
that the time needed to
establish the conditions for a resistivity
independent dissipation is
finite and does not depend on the magnetic
Reynolds number.
EUV and radio observations of an equatorial
coronal hole:
a model of the upper transition region
and corona
F. Chiuderi Drago1,
E. Landi2, A. Fludra3
and A. Kerdraon4
1 Dipartimento di Astronomia e Scienza
dello Spazio University of Florence, Italy
2 Max-Planck-Institute Aeronomie, Katlenburg-Lindau,Germany
3 Rutherford Appleton Laboratory Chilton,Didcot,
UK
4 DASOP-Observatoire de Paris Meudon,
France
Using the intensity of several EUV lines
observed by SOHO-CDS in an
equatorial Coronal Hole, the dem function
DEM(T)=Ne2 dh/dT is derived
in the temperature range 104 - 106. Above
the temperature where no more
lines are detected, the dem can be either
truncated or arbitrarily
extrapolated to a very low value at a
very high temperature. The dem
derived with both assumptions reproduce
very well the observed line
intensities, but are unable to reproduce
the observed radio brightness
temperature,Tb. It is shown that the observed
radio Tb can be obtained
only by postulating the presence of an
isothermal Corona above the
region where the dem is defined. From
the fit of the Tb, observed by the
Nancay Radioheliograph in the same hole
at four frequencies between 164
and 410 MHz, a full model of the Coronal
Hole is derived which fits also
the EUV line intensities.The electron
density, derived from the coronal
emission measure in the hydrostatic equilibrium
assumption, disagrees
with that derived from density sensitive
line ratio: the reason of this
discrepancy is discussed.
On the purposes of Georgian-Turkey joint
group at Solar eclipse in Elazig
Gigolashvili M. Sh, Khetsuriani Ts.
S., Khutsishvili E. V., Geonjan
L. A., Kiladze R. I., Salukvadze G.
N., Japaridze D. R., Meier A. K.,
Kapanadze Z. G. et al.
Abastumani Astrophsical Observatory,
Tbilisi, Georgia
The tasks and aims of undertaken expedition
as well as short description
of used instruments are given. The prospective
results of eclipse
observation are briefly discussed. The
problems of further investigation
of the corona, our intends about improved
or new instruments and our
wishes about organising of the joint expedition
for observing next total
solar eclipse in 2001, are presented.
Solar variation of cosmic ray intensity
G. Kandemir1
and S. Boydag2
1 Department of Physics, Istanbul
Technical University, Istanbul, Turkey
2 Department of Physics, Yildiz
Technical University, Istanbul, Turkey
Intensity variation of cosmic rays and
its dependence on various factors
are important for understanding the interplanetary
medium. Primary cosmic
rays observedin the interplanetary system
have galactic and extragalactic
origin. Their intensity is known to vary
inversely with the intensity of
the solar wind. We imply the solar effect
on primary cosmic rays in the
interplanetary space by using the term,
the solar modulation. The diurnal
variation and the 27-day variation of
secondary cosmic ray particles may
be considered as a second type of solar
modulation observed from the
earth.Recently, the effect of cosmic rays
on the climate has been a
popular issue. These investigations are
concerned with the interplanetary
modulation rather than a local effect.
It is suggested in our paper
that a solar eclipse may serve to test
such a local effect. During a
total solar eclipse, solar effect changes
only on a narrow corridor
while it remains the same at the other
parts of our planet.
The possibility of a variation in the
local secondary cosmic ray density
at a total solar eclipse site is questioned
in this paper. Precision of
a mobile experimental set-up is given
as an example. It is discussed
whether the expected value is sufficient
to allow significant measurements
or not. Finally, we have proposed that
such observations may reveal the
impact of local secondary cosmic rays
on the climate.
Estimating the characteristic size of
the fine coronal structure
M. Karovska1
and T. S. Zaccheo2
1 Harvard-Smithsonian Centre for Astrophysics,
Cambridge, USA
2 MIT Lincoln Laboratories, Lexington,
USA
The images of the solar corona obtained
during solar eclipses contain
many complex components with different
spatial scales and a wide range of
contrast levels. Spatial characterisation
of these components is extremely
important for understanding the characteristics
of the small-scale
structure in the corona. We describe here
two image-processing techniques
that we have applied to solar images from
the 1991 eclipse taken by
S. Koutchmy (November & Koutchmy,
1995).
We developed an adaptive gradient based
enhancement algorithm to extract
the fine coronal structure from the average
solar background, and employed
small block Fourier analysis to estimate
the frequency of these features.
The gradient based technique used in this
work was a modified version of
the image enhancement algorithm originally
proposed by S. Koutchmy,
which we have applied in the past to a
large number of space-based
observations of the solar corona. Simulated
data with known regular
structures were also used to validate
the analysis.
Overall, the data analysis indicates quasi-periodicity
of the spacings
between the small- structures within the
streamers and the loop-like
structures. Most of the streamer elements
are spaced approximately 15
arcseconds apart, and there is possibly
a second fundamental period of 9
arcseconds per cycle. The analysis also
suggests that the elements
within the loop-like structures be separated
by approximately 14
arcseconds.
We conclude that these techniques provide
a powerful tool for extracting
information on the morphology and the
characteristics spatial scales of
the fine coronal structures buried in
a slowly varying background.
Eclipse curves of CaII H K structures
M. Makita
Gakuin Jr. College, Osaka, Japan
Eclipse curves of 24 CaII H K and H( structures
obtained from the flash
spectrum of 12 October 1958. Some CaII
H K spicule-like structures
extend to the height more than 104 km.
Under the coronal condensation
the emission is enhanced by two and three
times for CaII and Ha structures,
respectively.
Internet relaying of total solar eclipse
on august 11, 1999
T. Nagai1,
N. Takahashi2 , M. Okyudo and Team of Live
Eclipses3
1 National Astronomical Observatory,
Tokyo, Japan
2 Meisei University, Tokyo, Japan
3 Misato Observatory, Wakayama, Japan
The total solar eclipse was relayed live
through the Internet from Siberia,
Russia, on March 9, 1997. Subsequently,
the total solar eclipse was
relayed from Venezuela and Guadeloupe
in the Caribbean Sea in February
1998, annular solar eclipse from Malaysia
on August 21, 1998, and annular
solar eclipse from Austria on February
16, 1999.The Internet will be used
to relay the total solar eclipse to be
seen in Europe, Rumania, Turkey,
and Iran.
Quantitative colour photometry of the
solar corona
Y. D. Park1,
I. S. Kim2, N. L. Kroussanova2
and Baskaran Deepak3
1 Korea Astronomy Observatory, Yusong-gu
WWTaejon, Korea
2 Sternberg State Astronomical Institute
of Moscow State University,Moscow, Russia
3 Astronomical Department of Physics
Faculty, Moscow State University,Moscow, Russia
Quantitative colour photometry and IDL
software are used to estimate the
"reddening" effect of the solar corona.
The slides of relative
calibration (wedge) and the eclipse white-light
corona of July 11, 1991
are revised. Digitising the colour films
by Perkin- Elmer microdensitometer
was made in the blue and the red spectral
intervals centred at 450 nm and
660 nm respectively. IDL data reduction
was based on the two suggestions.
Firstly, colour of the K-corona indicated
by the large-scale streamers is
similar to the solar disk one. Secondly,
the colour index
(CI = I660 / I450) equals 1 within the
inner part of the large-scale
NE-streamer (P (37( , R = 1.15-1.30 Rs).
Distribution of the CI is
presented for the whole corona. CI is
noted to be different within
different coronal structures. The "reddening"
as well as it's increasing
with distance are found in the range <3
Rs. Integration along the line
of sight and correct absolute calibration
seem to be crucial for searching
the "reddening" effect deduced from intensity
distribution in the
picture plane.
Sunblock '99 - an educational resource
C. D. Pike1,
H. E. Mason2 and R. W. Walsh3
1 Rutherford Appleton Laboratory, Didcot
, UK
2 University of Cambridge, USA
3 University of St. Andrews,St. Andrews,
UK
In response to the interest generated by
the solar eclipse,
the SunBlock '99 website (www.sunblock99.org.uk)
has been created to
increase awareness of solar physics in
general. Different solar topics
are presented each one by a young researcher
from the UK. They describe
not only the science, but also their lives
and how they became interested
in studying the Sun. The educational content
is aimed at secondary
school children and much of the material
is designed to fulfil the
requirements of the UK national curriculum.
Solar induced extrasolar nuclear reactions
M. S. Spergel
York College of CUNY, Jamaica, NY,
USA
It is propose that several of the anomalous
isotopic abundances seen in
meteoric and planetary surfaces are be
due to nuclear reactions between
the high energy component of the Solar
Wind and interplanetary material.
It is suggested that this process would
operate most efficiently early
in the history of the solar system. During
the T. Tauri, solar wind stage
within a solar nebula, solar wind particles
of velocities > 300 km/s,
correspond to Solar Wind Energy of >1KeV
or Wind temperature>10 Million
degrees K, would provide the necessary
energy projectiles for nuclear
reactions. Targets nuclei would be the
ambient solar nebula.This paradigm
extends work found in papers by R. Ramaty,
R. Lingenfelter, M. Spergel
and others who have examined extra-stellar
nuclear reactions.
The production will occur at the interface
between the emerging Sun's
HII region and the neutral solar nebula
plasma. Secondary neutron
production from the direct solar wind
interaction with the plasma will
extend the region of nuclear reactions
deeper into the solar plasma.
In the present epoch extra-solar nuclear
isotope production would be
expected to continue in the realm of the
airless close asteroids, Mercury
and the Moon as well as in the atmosphere
of Venus with its essential
null magnetic fields.
Large-scale distribution of coronal
temperature observed at the total solar eclipse
on 26 February 1998
N. Takahashi1,
E. Hiei1 and K. Ichimoto2
1 Hodokubo Hino, Tokyo, Japan
2 National Astronomical Observatory,
Tokyo, Japan
On February 26, 1998, the total solar eclipse
was observed at Anse
Bertrand located at the northeast end
of Guadeloupe (French territory).
By means of four wavelengths of 3980A,
4100A, 4220A, and 4320A of
continuous spectrum of corona, corona
images were photographed with a
combination of polarising filters. Directly
from these images, it is
possible to derive the two-dimensional
electron temperature distribution
of the corona. This method is principally
the same as the measurement of
coronal electron temperature through spectral
observation conducted by
the National Astronomy Observatory at
the time of the total solar eclipse
in South America in 1994. From the images
obtained, temperature difference
between streamer and polar plume, temperature
of coronal hole estimated
from the polar plume, etc, were reported.
Density structure of the coronal loops
derived from the 1991 total eclipse observation
A. Takeda, H. Kurokawa, R. Kitai, and
K. Ishiura
Kwasan Observatory, Kyoto University,
Kyoto, Japan
We present some results of the quantitative
analysis on the coronal
loops, which are distinguished in the
green and red emission-line images
obtained at the total solar eclipse of
11, July 1991. Four green-line
and eight red-line loops were examined,
for each of which the intensity
profiles across the loop were measured
at several heights, the background
intensity levels were subtracted, and
the intensity and width (diameter)
of the loop defined as the maximum intensity
and the FWHM of each
subtracted profile, respectively, were
obtained. From these quantities,
the electron densities, intensity contrasts
of the loops, and so on was
calculated using the emissivity table
by Mason (1975).
In terms of the distribution of the electron
densities, it seems that
there is little difference between the
green and red-line loops except
innermost region. They are generally in
the range of 5 - 20 x 108 cm-3 at
the portion below 1 x 105 km, and around
5 x 108 cm-3 at the portion of
1 - 2 x 105 km, whereas, in several red-line
loops, the densities exceeds
2.0 x 109 cm-3 at the innermost portion.
The height variation of these electron
densities are compared with those
expected in case of hydrostatic equilibrium
by assuming that the observed
loops locate in the plane of the sky.
As the result, we find no
significant deviation from the hydrostatic
curve in the green-line loops.
By contrast, only a half of the red-line
loops seem to be in hydrostatic
equilibrium, whereas in the other loops,
and electron densities do not
decrease so much as the hydrostatic case.
Study of an emerging flux region observed
with TRACE
S. Yashiro1
and K. Shibata2
1 Dept. of Astronomy, Univ. of Tokyo,
Sagamihara, Japan
2 Dept. of Astronomy, Kyoto University,
Kyoto, Japan
We study the early evolution of an active
region in the corona by
analysing one emerging flux region observed
with the TRACE and Soft X-ray
Telescope aboard Yohkoh. This region appeared
around 8-Jun-98 02:11 UT
near the west limb, and grew into the
large active region.In the TRACE
data, we can clearly see many emerging
magnetic loops during 1 day after
emergence, and we examine their apparent
velocities. The velocity of
dark feature is about 15 km/s and the
velocity of bright loop is about
5 km/s (Dark and Bright features correspond
to 104 K and 106 K plasma,
respectively). These velocities are almost
same as both Ha arch filament
and prediction from theory. In the case
of Yohkoh, we can not see the
emerging loop directly like TRACE observation.
For that reason,
we calculate the time variation of size
of this active region, and then
we obtain the apparent expansion velocity
of 1 km/s. We will discuss a
possibility to account for the difference
between TRACE and Yohkoh
observations.
List of Participants
ADUR, Bharat
e-mail: bharatadur@hotmail.com
Dr. Annie Besant Road,
Worli, Mumbai, 400 018 INDIA
AKIYAMA, Sachiko
e-mail:akiyama@flare2.solar.isas.ac.jp
Yohkoh Data Analyze Center, /o Prof. Y.
Ogawara, Institute of Space and Astronautical
Science , 3-1-1 Yoshinodai, Sagamihara,
Kanagawa 229-8510, JAPAN
ALTAS, Levent
e-mail:altas@boun.edu.tr
Bogazici University, Kandilli Observatory
and
Earthquake Research Institute
81220 Cengelkoy , Istanbul, TURKEY
ATAC, Tamer
e-mail:atac@boun.edu.tr
Bogazici University, Kandilli Observatory
and
Earthquake Research Institute
81220 Cengelkoy , Istanbul, TURKEY
BASKARAN, Deepak
e_mail: deepak@sai.msu.su
Sternberg Astronomical Institute
Moscow State University
Universitetsky pr.13.
Moscow 119899, RUSSIA
BELINSKI, Alexandre A.
e-mail:aleks@sai.msu.su
Sternberg Astronomical Institute
Moscow State University
Universitetsky pr.13.
Moscow 119899, RUSSIA
BELVEDERE, Gaetano
e-mail:gbelvedere@alpha4.ct.astro.it
Institute of Astronomy, Catania University
Citt... Universitaria,
Via S. Sofia, 78 , Catania, I-95125 ITALY
BOUGAENKO, O. I.
e-mail:kim@sai.msu.su
Sternberg State Astronomical Institute
of
Moscow State University,Moscow, RUSSIA
BOLGE, Arzu
Bogazici University, Kandilli Observatory
and
Earthquake Research Institute
81220 Cengelkoy , Istanbul, TURKEY
BOLGE, Hasmet
e-mail:bolgehas@ boun.edu.tr
Bogazici University, Kandilli Observatory
and
Earthquake Research Institute
81220 Cengelkoy , Istanbul, TURKEY
CACCIANI, Alessandro
e-mail:Alessandro.Cacciani@roma1.infn.it
Physics Department , Univ. "LA SAPIENZA"_
P. Aldo Moro,2
00185 Rome, ITALY
CAGLAR, Ilyas
e-mail:caglari@itu.edu.tr
Istanbul Technical University,
Faculty of Mines, Geophysics Department,
Maslak 80626, ~stanbul, TURKEY
CHIUDERI, Claudio
e-mail:chiuderi@arcetri.astro.it
Department of Astronomy, University of
Florence, Largo Enrico Fermi, 5
50125 Firenze, ITALY
DERMENDJIEV,Vladimir, N.
e-mail:vlderm@astro.bas.bg
Bulgarian Academy of Sciences
Institute of Astronomy
72 Tzarigradsko chaussee Blvd.
1784 Sofia, BULGARIA
DIVLEKEEV, Michail, I.
e-mail:kim@sai.msu.su
Sternberg State Astronomical Institute,
Moscow State University ,
Moscow 119899, RUSSIA
DRAGO CHIUDERI, Franca
e-mail:fdrago@arcetri.astro.it
Dept. Astronomy, University of Florence
Largo Enrico Fermi,
5 50125 Firenze, ITALY
DUZGELEN, Ayten
e-mail:duzgelen@ boun.edu.tr
Bogazici University, Kandilli Observatory
and
Earthquake Research Institute
81220 Cengelkoy , Istanbul, TURKEY
ESPENAK,Fred
e-mail:espenak@gsfc.nasa.gov
NASA/Goddard Space Flight Center
Code 693
Greenbelt, Maryland 20771, USA
FAUROBERT, Marianne
faurob@obs-nice.fr
Observatory of Nice
BP 4229
F-06304 Nice Cedex 4, FRANCE
GIGOLASHVILI, Marina Sh.
e-mail:marinagig@yahoo.com
Abastumani Astrophysical Observatory
Alex. Kazbegi Ave 2a,
380062,Tbilisi, GEORGIA
HIEI, Eijiro
e-mail:hiei@corona.mtk.nao.ac.jp
2-1-1, Hodokubo, Hino,
Tokyo, 191- 8506, JAPAN
ICHIMOTO, Kiyoshi
e-mail:ichimoto@solar.mtk.nao.ac.jp
National Astronomical Observatory of Japan
Osawa, Mitaka
Tokyo 181-8588, JAPAN
KIM, Iraida
e-mail:kim@sai.msu.su
SAI of Moscow University
Universitetskij Pr 13
119899 Moscow, RUSSIA
KANDEMIR, Gulcin
e-mail:kandemir@sariyer.cc.itu.tr
Istanbul Technical University, Dept. Physics
80626 Maslak, Istanbul, TURKEY
KAROVSKA, Margarita
e-mail:karovska@head-cfa.harvard.edu
Harvard-Smithsonian Center for Astrophysics
60 Garden Street
Cambridge, MA 02138, USA
KHAN, Josef I.
e-mail:khan@isasxa.solar.isas.ac.jp
Institute of Space & Astronautical
Science
3-1-1 Yoshinodai, Sagamihara,
Kanagawa, JAPAN
KULIJANISHVILI, Vaja
e-mail:kvaja@kheta.ge
Abastumani Astrophysical Observatory,
Academy of Sciences of Georgia, 383762,
Mount Kanobili, Abastumani,
GEORGIA
LIVINGSTON, William
e-mail:wcl@noao.edu
National Solar Observatory
Box 26732
Tucson, AZ 85726, USA
LOMINADZE, Jumber
e-mail:jlomin@parliament.ge
Director of the Abastumani Astrophysical
Observatory,
A. Kazbegi av. 2A, Tbilisi, 380060
B. GEORGIA
MAHMOUDI, Farvah
e-mail:fmahmoudi@student.ulg.ac.be
Chemin de la Dri, 16A 4051
Chaudfontain, BELGIUM
MAKITA, Mitsugu
e-mail:makita@kusastro.kyoto-u.ac.jp
Osaka-Gakuin Jr. College
Osaka, JAPAN
MIKIC, Zoran
e-mail:mikic@iris023.saic.com
Science Applications International Corporation
0260 Campus Point Drive
San Diego, CA 92121, U.S.A.
MINAROVJECH, Milan
e-mail:milanmin@auriga.ta3.sk
Astronomical Institute,
Slovak Academy of Sciences,
059 60 Tatransk Lomnica, SLOVAKIA
NAGAI, Tomoya
e-mail:nagai@th.nao.ac.jp
2-21-1 Ohsawa
Mitaka Tokyo, 181-8588, JAPAN
OFMAN, Leon
e-mail:leon.Ofman@gsfc.nasa.gov
Raytheon ITSS/NASA GSFC
Code 682
Greenbelt, MD 20771 USA
OKTEN, Adnan
e-mail:adnan@astronomy.sci.ege.edu.tr
Istanbul University Observatory Application
and Research Center
34452 Istanbul, TURKEY
OZGUC, Atila
e-mail:ozguc@ boun.edu.tr
Bogazici University, Kandilli Observatory
and
Earthquake Research Institute
81220 Cengelkoy , Istanbul, TURKEY
OZKAN, M. Turker
e-mail:ozkant@istanbul.edu.tr
Istanbul University Observatory
Application and Research Center
34452 Istanbul, TURKEY
PALETOU, Frederic
e-mail:paletou@themis.iac.es
Telescopio Themis Inst. Astrofisica de
Canarias
Via Lactea S/N E-38200
La Laguna, Tenerife, SPAIN
PARK, Young Deuk
e-mail:ydpark@hanul.issa.re.kr
Korea Astronomy Observatory San 36-1,
Whaam-dong, Yooseong-gu Taejeon
305-348 SOUTH KOREA
PIKE , C David
e-mail:c.d.pike@rl.ac.uk
Rutherford Appleton Laboratory
Chilton, Didcot, Oxon OX11 0QX, UK
POLAND, Arthur I.
e-mail:poland@sohops.gsfc.nasa.gov
682 NASA/Goddard Space Flight Center
Greenbelt MD 20771, USA
RAOUAFI, Nour-Eddine
e-mail:raouafi@medoc-ias.u-psud.fr
Institut d'Astrophysique Spatiale
Universite Paris XI - Bat. 121 _91405
Orsay Cedex , Paris, FRANCE
RUSIN, Vojtech e-mail:vrusin@auriga.ta3.sk
Astronomical Institute,
Slovak Academy of Sciences,
059 60 Tatransk Lomnica, SLOVAKIA
SALTIK, Metin
e-mail:saltik@esentepe.sau.edu.tr
Sakarya sniversitesi Muhendislik Fakultesi
Esentepe Kampusu
54100 Adapazari, TURKEY
SELEZNEV, Denis A.
e-mail:ifg@aha.ru
M.Ulianovoy st.
9-1-75, Moscow, RUSSIA
SIM,Kyung Jin
e-mail:kjsim@hanul.issa.re.kr
Korea Astronomy Observatory
Wha- amdong 61-1, Yusong-gu Taejon
SOUTH KOREA
SPERGEL, Martin S.
e-mail:cosmic@neptune.york.cuny.edu
Department of Natural Sciences York College
of the City University of New York
Jamaica, NY, 11541 USA
SOZEN, Engin
e-mail:sozenm@ boun.edu.tr
Bogazici University, Kandilli Observatory
and
Earthquake Research Institute
81220 Cengelkoy , Istanbul, TURKEY
STENFLO, Jan O.
e-mail:stenflo@astro.phys.ethz.ch
Institute of Astronomy
ETH Zentrum
CH-8092 Zurich , SWITZERLAND
TAKAHASHI, Noritsugu
e-mail:takahasn@ge.meisei-u.ac.jp
2-1-1 Hodokubo Hino,
Tokyo 191-8506, JAPAN
TAKEDA, Aki
e-mail:takeda@kusastro.kyoto-u.ac.jp
Yamashina-ku,
Kyoto, 607-8471, JAPAN
UENO, Satoru
e-mail:ueno@kwasan.kyoto-u.ac.jp
Hida& Kwasan Observatories
Kyoto University,
Kyoto, JAPAN
UCER, Cumhure
Bogazici University, Kandilli Observatory
and
Earthquake Research Institute
81220 Cengelkoy , Istanbul, TURKEY
YONESHIMA Wakako
e-mail:yonesima@phys.meisei-u.ac.jp
2-1-1 Hodokubo Hino Tokyo,
191-8506, JAPAN
YASHIRO, Seiji
e-mail:yashiro@flare2.solar.isas.ac.jp
Yohkoh Data Analyze Center,
c/o Prof. Y. Ogawara, Institute of Space
and Astronautical Science 3-1-1
Yoshinodai Sagamihara 229-8510, JAPAN
YESILYAPRAK, Hulya
e-mail:yesilyap@boun.edu.tr
Bogazici University, Kandilli Observatory
and
Earthquake Research Institute
81220 Cengelkoy , Istanbul, TURKEY
The last total solar eclipse of the millennium
in Turkey
13-15 August 1999, Istanbul