The Sky at Night host Sir Patrick Moore is "doing extremely well" sitting up in bed and reading after having a pacemaker fitted, his agent has said.
Sir Patrick Moore has had a pacemaker fitted in hospital today
The 83-year-old astronomer's agent, Robert Voice, said the presenter of the long-running BBC programme was likely to be home in a few days.
Sir Patrick was admitted to hospital on Tuesday, and had the heart regulator inserted after feeling tired.
"Nothing keeps this man down, he's fantastic," Mr Voice said.
He added there was a slim chance that Sir Patrick would be discharged from St Richard's Hospital in Chichester, West Sussex, this weekend.
Sir Patrick has presented the BBC's monthly programme on astronomy since 1957.
He has also written more than 60 books and received his knighthood in 2001.