George R.R Martin may be working on the sixth book in the Song of Ice and Fire saga though he's already turning attention to his next project. The writer is penning a new television series titled Captain Cosmos about "a visionary young writer [who] creates a science fiction series that tells stories no one else will dare to tell," according to Entertainment Weekly.

George R R MartinGeorge R. R Martin has had massive success with Game of Thrones, though he's now working on Captain Cosmos

Martin inked a two-year development deal with HBO back in 2013 and has been working on Captain Cosmos while working on his next book, The Winds of Winter. The series is said to take place "at the dawn of the age of TV in 1949."

For now, HBO is yet to formally announce Captain Cosmos and is busy preparing the fifth season of Game of Thrones for its premiere on April 12.

More: George R R Martin writes on DOS. Won't even entertain Microsoft Word.

"I wish it was out now," Martin said of The Winds of Winter. "Maybe I'm being overly optimistic about how quickly I can finish. But I canceled two convention appearances, I'm turning down a lot more interviews-anything I can do to clear my decks and get this done."

Asked to predict how the new book might compare to previous entries in the series, Martin said: "On Tuesday, I think it's the greatest thing I've ever done," Martin says. "On Wednesday, I think it's all garbage and I should throw it all in the fire and start again."

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