Actor Sushant Singh Rajput, who is currently gearing up for “Chanda Mama Door Ke”, says preparing for the movie is helping him get to know his childhood dream. Sushant on Sunday shared a photograph of a notebook, which read: “Theory Of Astronaut Training.” The actor said he is really excited to prepare for his role in the film. “Really excited to start this. Getting to know my childhood dream ‘Chanda Mama Door Ke’. Sanjay P. Chauhan, Viki Rajani,” captioned the image. Sushant, who was last seen on screen in the biopic “M.S. Dhoni: The Untold Story”, will reportedly be playing an astronaut in Sanjay Puran Singh Chauhan’s directorial. Other details about the space adventure film are still under wraps.