2004 ASTRONOMY & ASTROPHYSICS - Indian Academy of Sciences

CHAPTER 3
on a site surrounded by a large water body
provide superior image quality over the entire
day. The prime examples are the Big Bear Solar
Observatory (California, USA), Udaipur Solar
Observatory (USO) of the Physical Research
Laboratory, and the Huairou Solar Station (Beijing,
China). The availability of good quality images has
been amply demonstrated over the past 25 years
of observations from the island observatory at
Udaipur where, on an average, about 265 days in
a year are clear. It would be important to urgently
undertake a re-evaluation of this site for a 50cm
class telescope. Assuming that the result of such a
critical evaluation would be positive, then given
the available infrastructure, expertise, and logistics,
the proposed telescope could be located on this
island site. Modern networking, remote operation,
and automation techniques should be employed
to allow this facility to be accessed and used by a
wide user community.
• A Spectrograph,
• A Polarimeter, and
• A Fabry – Perot based Universal Filter.
The polarimeter could be integrated with the
telescope and positioned before the first oblique
reflection. The spectrograph could be on a stable
platform and fed by a beam extracted from the
telescope. The narrow band filter will be used for
obtaining magnetograms, as well as dopplergrams.
The primary objective of such a telescope will be
to study the solar activity phenomena from the
Indian longitude belt in which modern solar
instruments are rare or non-existent. By keeping a
target of obtaining vector magnetograms at a
spatial resolution of 0.4 arcsec and longitudinal
magnetograms, as well as dopplergrams, at a
resolution of 0.2 arcsec, we would be competitive
in certain areas, and complementary in other areas
on the global scene.
It would be desirable if such a telescope has at
least three major back-end instruments:
Other
Recommendations
Solar Data Archival Centre
There has been a great tradition in astronomy of
sharing data. During the past two decades or so,
data archives have been effectively mined by
countless number of astronomers. The Virtual Solar
Observatory and the International Virtual
Observatory are being set up.
Keeping in mind these developments, it
would be highly desirable to set up a solar
data archival centre. The Kodaikanal
Observatory of the Indian Institute of Astrophysics
possesses a rich collection of synoptic data going
back to almost hundred years. This data, which is
presently on photographic plates and films, should
be digitized. With the use of a good link to the
Kodaikanal Observatory, such a centre (possibly
based at IIA, Bangalore) will be able to provide
online and updated synoptic data to the solar
astronomy community all over the world. Similarly,
the data being generated at Udaipur and at
Nainital from optical observations, and the radio
observations from the GMRT, the Ooty Radio
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