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ROT-54 presentation Armenia

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Radio Optical Telescope
ROT-54/2.6
Dr. Arevik Sargsyan
Herouni United Space Center (HUSC), Armenia
EVN CBD meeting, May 12, 2021
Where we are?
ROT-54 is placed in Aragatsotn region of the Republic of
Armenia, on the southern slot of mount Aragats, which is the
highest pic in Armenia.
ROT-54
The Latitude:
40.3508609°
The Longitude:
44.2417924°
The Altitude:
1711 m
Antenna
Parameters
Design peculiarities of the
ROT-54/2.6
Professor Paris Herouni
The ROT-54/2.6 includes the Radio Telescope
with Double Reflector Spherical Antenna with
the main reflector 54m in diameter (an
effective diameter is 32m) and secondary
reflector of 5m aperture diameter, and the
Optical Telescope with diameter of mirror
2.6m and focus distance of 10m.
Schematic view East - West (ICAP 1989, P.M. Herouni “The First Radio Optical Telescope
The main symmetry axis is oriented
towards a direction 15° to “South”
leaving 15° with respect to the local
zenith at 40°, the latitude of the location
of the telescope. A beam pointing is
available from -35° elevation (“South”)
to +85° elevation (“Nord”).
Apical angle of the conical view is 120°.
ROT-54/2.6 history
ROT-54/2.6 history-1
The construction: 1980-1985.
Finishing adjusting works in 1987.
In 1987, the radiotelescope was put into operation. This type of radiotelescope
was named Herouni Mirror Telescope. The devastating earthquake of 1988,
fortunately, did not affect the structure of the antenna, which confirms the
highest level of the antenna engineering project, the infallibility of
technological solutions, and the stability of the structure.
A hemispherical large reflector with a diameter of 54 meters and a small
reflector with a special profile shape, the aperture of which is 5 meters. The
hemispherical reflector is unmovable and is built in natural concavity, in a
concrete bowl.
ROT-54/2.6 history-2
Planned observations under the management of Professor Herouni were done
in 1987 – 1990. The Explosion of Red Giant Star was recorded (Etta star in
Gemini constellation), multiple scientific articles were published in USSR
periodical and abroad, Professor Paris Herouni has participated and presented
results about ROT construction and parameters in a big number of International
Conferences.
ROT-54/2.6 history -3
During the energy crisis of 1990-1995, numerous measurements of
antenna parameters using the radio astronomical method were
performed, new radio sources were registered by Professor A. Sargsyan
and a group of young scientists and students led by her.
Restructuring works on Radio telescope's managing system’s
computational system were done (1995-2010). Replacing by PC, adjusting
and new special software programming works, renovation and design of new
feeding antennas, modernization of feeding system of Antenna were done,
scientific collaboration with Astronomical Society of Russia and National
Technical University of Athens were organized in a different topics, a
number of National Polytechnic University of Armenia students have
done their Bachelor, Master and Ph.D. graduating thesis's here.
ROT-54/2.6 history -4
Within the framework of financing from the state budget, some preventive
actions were carried out year after year, till 2011.
During the last five years of that period, some parts of the antenna’s
management and control system were dismantled, some radio electronic
plates of the devices disappeared, and however, the mechanical structure of
the antenna is in good condition and can serve its purpose.
Theoretical and experimental work on the antenna has been carried out in
the last 30 years under the condition of very limited funding, mainly due to
the free dedication of the staff.
ROT-54/2.6
today
After the reorganization of scientific and technical institutions of the
Ministry of Economy of the Republic of Armenia in 2012, the ROT54/2.6 unique radiotelescope did not serve its purpose at all.
According to the decision of the National Body of Standards and
Metrology (NBSM) leadership, the ROT-54/2.6 antenna is preserved
because of the lack of funds. Thus, the instrument is not financed by the
state budget, as well as by other sources. It doesn’t work still 2012.
Currently the East-West axis is blocked on
purpose with welded brackets. The East –
West axis is not damaged: it is only fixed by
welding. It will function after repairing of
the Connecting Rod (Brackett).
After the long stop of the Antenna of the ROT-54/2.6 it was necessary to collect and
analyze data about possible metal fatigue of the mechanical construction of tripod
and the pendulum carrying the secondary mirror.
ROT’s Mechanical construction Inspection, as well as the Inspection
of Cardan assembly, axis, suspension, motors, el. current supply
cables etc. was organized in September, 2020
Beside the known problems with rust and the broken lever, another crack in a
welding of the secondary support arm was found. This needs to be welded
again when the other tasks are being performed, like lubrication of the
bearings, anti-corrosive protection, and the repair of the lever of the EastWest.
Recordings of sky signal on ROT-54: Test 1
A first recording of the sky signal at 4.5 GHz during 24h was performed as a Test 1.
Recordings of sky signal on ROT-54: Test 2
In December 2020 two more recordings of the
sky signal around the time of the passage of
the Cygnus region were conducted. The first
recording was done on December 3rd and the
second recording 13 days later on December
16th. Without any direct source identification
this data should allow to detect the time shift
of the pattern between the two dates. Indeed,
some remarkable structures appear time
shifted between the two epochs of recording
which likely originate from astronomical
sources. Some uncertainties remain in the
exact time stamps of the data, but a similarity
of the two track is noticeable. A full report can
be found on the wiki pages:
https://www.jive.eu/jivewiki/doku.php?id=ztrack
Current status
Advisory Group
HUSC applied to the EVN JIVE for conducting scientific-technical expertise of the
ROT-54/2.6 radio-optical telescope.
The Advisory Group (AG) was formed. The list consists from 10 Experts from
around a world.
The AG agreed on “Terms of Reference” for the future work. Further discussions via
email and a “Mattermost” chat server have been done.
A collection of documents about the ROT-54/2.6, the HUSC project, the AG
members, and the minutes of the meetings can be found on the Joint Institute for
VLBI in Europe (JIVE) wiki: http://www.jive.nl/jivewiki/doku.php?id=husc:husc_armenia
The first Report of AG was published on April, 2021.
Although many of the AG members haven’t had the chance to visit the
observatory until today, there are a number of documents that provide a
lot of details about the current situation at the observatory and the
technical details, e.g. Kees van’t Klooster’s report from a visit in 2018
(see the report in wiki: http://www.jive.eu/jivewiki/lib/exe/fetch.php?media=husc:rot_54_status_v1.pdf ).
It precisely documents the current status and describes the required works
to re-activate the antenna well.
The Sun reflected from the main spherical mirror
“Reflection varies gradually from panel to panel and is a reasonable indication that even today the
panel setting might well be acceptable for operation in the centimeter wavelength regime.”
Ir. MSc. C.G.M. van ‘t Klooster
Formerly Antenna Specialist European Space Agency (ESA), technical center Estec, Noordwijk, NL.
Email: kvtklooster@gmail.com
Orbital radar image of ROT taken in C band
Image provided by Kees van 't Klooster <kvtklooster@gmail.com>
A Possible L-band Receiver for ROT-54
John Sarkissian OAM – Operations Scientist
18 September 2020
CSIRO Astronomy and Space Science
Action list (according to the AG Report)
 Fixing the lever on the East-West axis should have the highest priority, as it is
required for any pointed measurements.
 Lubrication of the bearings and movable parts.
 Implement anti-corrosion measures.
 Planning for re-cabling: electrical engines, power and data connections for
receivers, optical fibres, sensors/encoders
 Install computers and software to control instruments, read antenna sensors, and
precisely control the positioning of the antenna.
 Install astronomical receivers and backends for continuum pointing, spectroscopy
and VLBI data generation.
 (VLBI) Data recording, storage, and transport.
 Connect the observatory with Internet.
The AG recognizes
the potential of the
ROT-54 antenna as a
single dish instrument
and in particular as an
element in the
European VLBI
network.
EVN CBD have sent
Supporting Letters to
the Prime-Minister of
Armenia.
(first: Dr. Rafael Bachiller​ on
June 17th of 2020 and the
second: Dr Tiziana Venturi on
March 16th of 2021; special
thanks to Dr. Francisco
Colomer for his efforts)
We need the Governmental decision on accumulate and transferring
necessary actives (material resources) from the NBSM to our
separate entity Herouni United Space Center (HUSC) - with the
state property again.
HUSC vision:
Acting and developing to presenting Armenia as an
advanced ideas and cutting-edge technologies state on
the scientific map of the world.
Keeping good traditions
Each year from 1968 till 1990 the All-union Conference
on Radio Telescopes and Radio Interferometers held in
Yerevan, Armenia (that time a part of the USSR).
There were a series of the All-union Conferences on
Antenna Measurements (ВКАИ) also organized by
Herouni’s Institute for long time.
After 30 years of the gap in the scientific activities field
in our country, we tried to revive the scientific heritage
of Professor Paris Herouni in Armenia.
XXIII International Conference on
Radio Telescopes and Radio
Interferometers (RR2020)
18th of September, 2020
Armenia-Nederland-Germany-Spain-Sweden-Australia-United Kingdom
Zoom meeting- videoconference
XXIV International Conference on Radio
Telescopes and Radio Interferometers
(RR2021)
Engineering and Scientific aspects of the revitalizing and modernization
of the ROT-54/2.6 Radio Telescope
"God has no intention of setting a limit to the efforts of man to conquer space".
Venerable Pope Pius XII
Panorama of the Ararat and the Tegher Monastery (XIII cent,) from the mount Aragats’ Radio-Optical Telescope
Thank you
Contacts: Arevik Sargsyan
Tel.: +374 91 409837 mob.
WhatsApp: +37491409837
E-mail: arevikantenna@gmail.com
HUSC FB: https://www.facebook.com/HerouniUnitedSpaceCentre
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