Spaceman Chris shares his odyssey with students

Most famous for his cover of David Bowie's 'Space Oddity', which he posted on YouTube from the International Space Station, Colonel Hadfield performed the track again - this time for members of the college's Philosophical and Law Societies.

He also received an honorary medal of patronage from the college in recognition of his achievements.

"My daughter went to Trinity and did her PhD there," said Mr Hadfield.

"I did a bit of work here for Tourism Ireland and made several videos touring around the country and it is a beautiful place," he added.

Col Hadfield also took time out as thousands queued over the weekend to meet him and get a signed copy of his new book.

'You Are Here - Around the World in 92 Minutes' is a selection of the astronaut's favourite images from his three trips to space.

He took thousands of pictures of the Earth while in space but could only select 150 for the book and said making the selection was difficult.

"I took 45,000 photographs and these are the 150 I chose so they all stand out," he said.

"Imagine what it was like to see the world that way, to be able to get a perspective where that is just a glance out the window where you can see 10,000 years of history of the world in one quick and quiet glance."

"It is an amazing way to get to know the planet better," he added.

He said there were certain things he was unable to get photographs of but he was not too disappointed.

"There are certain things that you would like to get a photograph of...like trying to get a photograph of the pyramids, Ayres Rock in Australia or some of the obvious things, but mostly the world delights with some of its unexpected detail," he said.

"The immense and changing beauty of it and it is a subject that never disappoints," he added.