Theory:

     To Duttada the telescope marked the fulfilment of the ambition of a lifetime. As an amateur astronomer he had longed for enough money to buy a good telescope and for enough spare time in which to observe the heavens. He got them both when he retired with ample money. The telescope was duly installed and long were the dark nights that Duttada spent in star-gazing. At least Indrani Debi thought so.
Explanation:
 
This eight-inch telescope held a special place in Duttada's heart since it meant everything to him and enabled him to meet his requirements. He had a secret goal in life that he hoped to accomplish with the aid of his beloved Dibya Chakshu.
 
Despite his lack of expertise as an astronomer, he was eager to get a telescope so that he could watch the stars. He also desired some free time in order to observe the celestial bodies. Both of his dreams came true once he retired, since he was free to conduct his work after retirement and the money he received at the time of retirement allowed him to buy a telescope. And, Dibya suited his needs. We can now understand why Duttada's wife was envious of his eight-inch telescope, as Duttada had spent more time on Dibya Chakshu gazing at stars. And, those dark nights seemed so long to Indrani Debi since she was alone without her husband.
 
Duttada observing stars.jpg
Duttada observing stars
 
Meaning of difficult words:
 
S.No
Words
Meaning
1.
Amateur
A person who lacks professional skills
2.
Envy
Wanting what someone has or wanted to be in the position where someone is
3.
Leisure
Free hour when you don't have work to do
4.
Gazing
To look at someone or something for a long time
5.
Ample
Often more than you need
Reference:
National Council of Educational Research and Training (2008). The Comet I - Jayant Narlikar (pp. 73-80). Published at the Publication Division by the Secretary, National Council of Educational Research and Training, Sri Aurobindo Marg, New Delhi.