USTM’s First Capture of an
Astronomical Event by Astronoscope-I
25th August, 2017, USTM :
Astronomical events like solar eclipse and lunar eclipse
are very exciting natural events which repeat after long
duration. During a solar and a lunar eclipse the sun and
the moon, respectively disappears for few hours
partially or totally. People eagerly wait to witness
such events while scientist performs different
experiments under the condition of such eclipses.
Seizing the opportunity of Lunar Eclipse that occurred
on 7th August 2017, visible from all the parts of India,
the Department of Physics at University of Science
and Technology, Meghalaya (USTM), had conducted a
scientific experimentation on Lunar Eclipse.
A group of M.Sc. Physics students, Mr. Mrinmoi K. Bora,
Mr. Ariful Alom, Mr. Rakesh G. Chetry and Mr. Ikbal
Farid Ali have developed USTM’s first optical telescope,
“Astronoscope-I” (Newtonian Reflector Type), under the
supervision of Mr. Nitu Borgohain, Assistant Professor,
Department of Physics. Astronoscope-I initially has the
maximum magnification 450X, which will be increased in
the upgraded versions of this telescope series. During
the time of the eclipse students and faculties of
different departments gathered to witness the event but
due to heavy cloud the initial phases of the eclipse
have missed. After 5 hours of wait few windows of
partially clear sky for 2-3 minutes have been found,
which were not to let go in vain and finally, the lunar
eclipse has been captured successfully at 11:45PM.
How Astronoscope-I was made?
The major parts of Astronoscope-I are the Telescope Tube
and the Mount. The Telescope Tube contains a convex
primary mirror of aperture diameter 4.5 inch and focal
length 900 mm at the bottom end, an oval structured flat
secondary mirror near the open tube end and a focuser
that holds the eyepieces mount outside the tube, near
the secondary mirror. These mirrors are bought from a
Mumbai based company which costs are around Rs. 5000
only. The telescope tube is made from a 1 meter long PVC
pipe of diameter 5.5 inch. The holder clamps of the tube
are made from scrap iron bars available in the RIST
workshop. The mount that has been developed is a
modified Dobsonian type which suspends the telescope
with the help of nut-bolt. A scrap revolving chair is
used for this purpose where the seat has been replaced
with a plywood mount made by the students.
How Astronoscope-I works?
Light enters the open end of the tube, travels down to
the primary mirror. The focused image then reflects back
to the small secondary mirror which is placed at an
angle of 450 with the primary mirror. Secondary mirror
reflects the image out through the side of the tube to
the eyepiece where it enlarged the object.
Magnification power of Astronoscope-I:
Magnification power of this type of telescope is given
by the ratio of focal lengths of the primary mirror to
the eyepieces. We have 3 different eyepieces viz. 20 mm,
12 mm and 4 mm, for which corresponding magnifications
with a 2X Barlow lens are 90X, 150X and 450X (maximum).
Thus with the help of Astronoscope-I, any distant object
in the night sky can be viewed maximum 450 times closer
then they appear.
What Astronoscope-I can gaze in the night sky:
The whole universe could be viewed in the night sky.
Moon is the easiest target to find at night. The craters
and mountains of the moon can be studied in much details
with Astronoscope-I. Other planets of the solar system
such as Venus, Mars, and Jupiter can also be viewed.
Rings of Saturn may be spectacular to be observed too.
Astronoscope-I also can be used for gazing the galaxies,
nebulae and star clusters abound in the deep sky and
study their formations.
Future Developments to Astronoscope-I:
Currently, Astronoscope-I has to be operated manually
for targeting an object in the sky. In the nearest
future, this discrepancy is to be removed with a digital
orientation system. A tuneable eyepiece system attached
with a HD camera also to be developed soon.
Department of Physics acknowledges the financial
support from Mr. M. Hoque, Chancellor, USTM.