The coronagraph-1 (KG-1) was designed by the State Optical and Mechanical Plant according
to the Lyot layout and put into operation in 1951. Positioned on the equatorial mounting,
it is a refractor with the 21-cm objective. The objective is made of glass K8. It is a
convex-plane lens 10 mm thick with the 350-cm focal length in the H-alpha 6562.8 Å line.
The telescope is used for chromospheric monochromatic observations of prominences,
filaments, active regions and flares in the H-alpha line. In the focal plane of the
objective there is a diaphragm cutting out a part of the solar image. Next to the
diaphragm there is another objective. Passing through it, a beam becomes parallel. Then
light falls on the diagonal mirror and interference-polarization filter (IPF). After IPF
light goes to the diagonal mirror, then to the lens of the field, and depending on the
rotary motion of the third diagonal mirror, either to the ocular or to the digital camera.
The focal length of this layout is 7 meters. The 12-cm image of the Sun is built up in the
focal plane. Optical resolution of the telescope is 1.5.
1 Interference-polarization filter Halle. The passband is 0.5 - 1 Å, a shift to wings up
to 1 Å is allowed. The temperature of IPF is controlled by a thermostat; working
temperature is 40.7 ?.
2 Digital camera Canon EOS 1000D, reflex camera with a portable objective, 10.50 million
pixels, matrix: 22.2 x 14.8 mm.
An image of a part of the solar disk (3888 õ 2592 pixels or 355.5 õ 266.6 angular
seconds in size) is taken with the digital camera. The image is oriented across the
diurnal circle. Observations are carried out in the center and in wings of the H-alpha
active regions and filaments on the solar disk, as well as prominences on the limb.
The archive of images in the H-alpha line is here.
Send notes and request to Shakhovskaya A.N. firstname.lastname@example.org
| Observation method
The synoptic maps are
built on observation data obtained at theTower Solar Telescope
BST-2 of the Crimean Astrophysical Observatory.
These data involve
areas of sunspot groups and intensity distribution of the HeI 1083 nm line across the
solar surface for each rotation of the Sun.
The areas of sunspot groups are detected based on sketches in white light of the
110-mm-diameter Sun's disk.
The HeI line intensity is determined by scanning the solar disk with a multi-purpose
The maps being built taking into account solar limb darkening and normalized to a unit are
filled with isophotes 0.9 typical for brightness in active regions and filaments and 1.02
typical for coronal holes.
The region defined by isophote 0.9 is marked in yellow and defined by isophote 1.02 - in
The position of sunspot groups for each observation day is indicated on the synoptic maps.
The area of a group is represented by a rectangle, lengths of sides are equal to
extension of the sunspot group. Individual sunspots are represented by dots.
Two vertical dashed lines correspond to the starting and ending
of the Carrington rotation. Dashes directed downward along the x axis
indicate longitudes of the central meridian (Lo) in moments of observations.
The archive of synoptic maps is here.
Send notes and request to Perebeynos V.A. email@example.com
daily relative numbers of sunspots (Wolf number) are the basic index of solar activity.
Daily index of sunspots activity R, defined as R="k" (10 g + s), where S the
number of separate sunspots, g number groups of sunspots are k-th the normalizing factor,
which considers difference in the sensitivity of the utilized tools and which leads the
observed values to the standard Zurich numbers.
k=1 for CrAO measurements.
The central zone of Sun is not included in the total amount of R = k (10 g + s) for the
Wolf numbers data -txt files (RNmmyy.htm),
where mm-month, yy-year in the form of tables (columns from left to right):
Day, hhmm-Universal Time (UT), s-quality visible image on a five-step scale (Seeing),
Ngr-number groups of sunspots, Nsp-the number of separate sunspots, W-daily index of
sunspots activity R (full-total Sun,
in N-hemisphere-northern hemisphere, in S-hemisphere-southern hemisphere, in central
zone-central zone of Sun)
Daily relative sunspot numbers click here
notes and request to Borisenko A.V. firstname.lastname@example.org