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.