Sun has been a constant source of energy for the past 4.5 billion years but it will eventually run out of fuel. Science ka Adda: Episode 10. Share this:FacebookTwitterGooglePinterestLinkedInEmailTumblrPrint One Response kalam bheek April 27, 2016 | Reply fabulous Leave a Comment Click here to cancel reply. Name * Email (will not be published) * Website Comment Notify me of follow-up comments by email. Notify me of new posts by email.