New voyage for The Hitchhiker's Guide to the Galaxy

Fans turn out for Hitchcon 2009, at London's SouthBank Centre, to celebrate the 30th anniversary of Douglas Adams's Hitchhiker's Guide To The Galaxy Photograph: Christian Sinibaldi

Large numbers of the fans at Hitchcon opted to sport dressing gowns, in tribute to the Guide's hero, Arthur Dent Photograph: Christian Sinibaldi

Three decades after The Hitchhiker's Guide to the Galaxy made its first appearance as a BBC Radio 4 serial, Douglas Adams's creation continues to attract new devotees Photograph: Christian Sinibaldi

Another fan holds two-headed toys, in tribute to Zaphod Beeblebrox, a famously double-skulled character hailing from a planet in the vicinity of Betelgeuse Photograph: Christian Sinibaldi

Fans at Hitchcon hold up early copies of Eoin Colfer's And Another Thing, "Part Six of Three" in Adams's Hitchhiker's Guide sequence, published today. Adams, who died in 2001, had intended to write a sixth, concluding part to his series of novels. Jane Belson, his widow, personally requested that Eoin Colfer, author of the Artemis Fowl books, take on the challenge of picking up the story. Photograph: Johnny Green/PA

Eoin Colfer (centre) joins fans at yesterday's Hitchcon event, coinciding with the launch of his sequel. Before publication Colfer had said: "I feel more pressure to perform now than I ever have with my own books, and that is why I am bloody determined that this will be the best thing I have ever written ... There are people out there that really want to like this book." Photograph: Christian Sinibaldi

Copies of Douglas Adams' Hitchhiker's Guide To The Galaxy on display at the SouthBank Centre in London at Hitchcon 2009 Photograph: Christian Sinibaldi

Eoin Colfer has spoken of his anxiety that his take on Douglas Adams's story does not disappoint its legions of fans. Early signs at yesterday's Hitchcon event should have reassured him Photograph: Christian Sinibaldi

Taking a break from Intergalactic questions at Hitchcon 2009 to catch up with the Sunday papers Photograph: Christian Sinibaldi

A banner flies above the Hitchcon event on London's South Bank. The slogan DON'T PANIC is said in Adams's story to adorn all editions of the Guide, to reassure readers intimidated by the insanely complicated operations of the device. It has since become one of the best-loved catchphrases to have emerged from the series Photograph: Christian Sinibaldi