Noted American astronomer and author (1934–1996) who became an international celebrity as writer and host of the landmark 1980 television series Cosmos. Two TLSs, one signed “Carl,” the other signed in full, both one page, dated 1981 and 1991 respectively. The 1981 letter, on Cornell University letterhead, reads: “Belated but very sincere thanks for your extremely generous letter about Cosmos. I am more pleased than I can say that you enjoyed the series. Any temptation I might have about doing more television programs of this sort is mobilized by letters such as yours.” In fine condition, with staple hole to top of one letter, and a spot of toning to the other letter. Accompanied by one of the original mailing envelopes. RRAuction COA.