First Light at Dongla Observatory

Hello Fellow Astronuts,

     I am indeed fortunate to be instrumental in installing the 20inch Planewave CDK telescope and photographing its First Light. 

     The observatory built by Madhya Pradesh Council of Science & Technology is situated at Dongla , Ujjain District and is the first observatory in the state of Madhya Pradesh. From the concept stage to the installation of the telescope, the observatory has shaped up at quite a fast pace.

     In the all-sky image below you can see the observatory dome as well as the facilities building just across. The area is surrounded by fields all around. (On my January visit I tried the fresh, large and wonderfully tasty 'Dollar Chana', which is grown in this area).

     This modern robotic observatory is located at the confluence of two important great circles - the ancient Indian Time Meridian and tropic of Cancer.  Time in India was reckoned from the longitude of Ujjain, and Tropic of Cancer is where the Sun lies at its northernmost in summers.

     The coordinates of Dongla Observatory are:

     Latitude:  23° 26' 42.91" N

     Longitude:  75° 45' 43.31" E

     Height: 515m

     You can see the site in Google Maps at this link.

     The observatory dome is of 5 metres diameter and installed at a height of 10 metres above the ground level. Construction of the structure and the dome has been done by Pedvak of Hyderabad.

Ajay Talwar & Tarun Bangia at the observatory floor

     Here are a few good men responsible for bringing shape to the observatory, from left - Dr. Tarun Bangia (ARIES Nainital), Mr. Bhupesh Saxena (MP-CoST Bhopal) and Dr. Padmakar Parihar (IIA Bengaluru).

     Climbing inside the dome we see the Telescope and the German Equatorial Mounting. The telescope is a 0.5 metre or a 20-inch Planewave CDK Telescope. It is a corrected Dall-Kirkham Astrograph. The word astrograph means that it is specially designed for photography and produces a flat field of 52mm diameter, without any curvature, off axis coma or astigmatism. The f/6.8 telescope has a apparent focal length of 3454mm. This focal length is quite interesting, it will produce a field of view on any sensor which will be equal to the dimension of the sensor in milimetres. So if you attach a full frame camera of dimension 36mm X 24mm, the field of view captured would be 36' x 24'.

     The Mounting is a German Equatorial from Paramount. This mounting is capable of robotic control. You can program the entire night of photography, and even control it over the ethernet.

     The CCD camera procured along with the telescope is the Apogee Alta U9000, a large format, 38 x 38mm square sensor with 3056 x 3056 pixels (9 megapixels) which will result in a field of view of 38' x 38'. The field of view is ideal for imaging medium and small galaxies. All the instruments have been supplied by Audo Viso Pvt. Ltd. of New Delhi.

     Well, as I said in the beginning, I am indeed fortunate to have been involved in setting up the telescope, balancing, polar aligning and conducting its First Light on the night of 10th June 2013. (The inauguration of the telescope was done by the Chief Minister of Madhya Pradesh Mr. Shivraj Singh Chauhan on 11th June 2013). Here are four photos of the First Light captured by my Canon 5D-II camera attached at the prime focus of the 20-inch Planewave CDK telescope.

     There are many large telescopes present in India, as large as 1 metre, 2 metres, 2.2 metres and upcoming 3.6 metre and 4 metre in the Himalayas. The size of this telescope  may seem to be small in front of other telescopes but it is no less important. This size of telescope fills an important need in astronomy research. The time available at large telescopes is limited and at a premium. In fact many such 'small' telescope are required across the country to fulfill the need of astronomy researchers and even amateur astronomers. This kind of observatory is also very important for outreach to all public, children.

     The unique capability of this telescope is that it can be programmed to collect data for entire night without human intervention. This makes this robotic observatory suitable for automated sky surveys to detect near Earth objects,  asteroids, supernovae in galaxies. This observatory can also be utilised for the new and important field of exo-planet discovery and confirmation. These are some exotic astronomy research fields prevalent in the world today. The Dongla observatory is capable of conducting all these research fields. 

Ajay Talwar
15th June 2013