Ever the science buff, Clarke curious to the last

Despite being crippled with post-polio syndrome and confined to a wheelchair, Arthur C. Clarke remained active in his twilight years. He was still greatly interested in space and the world around him. Clarke, who died on Wednesday and whose funeral was yesterday, had mastered the internet and scanned it for latest developments in science and technology, while communicating with friends and admirers by e-mail.

As he approached 90, Clarke zealously followed space probes to Mars, hoping evidence of life might emerge. 'So far there has been nothing,' he told me during a visit to his Colombo house in 2004. But he remained optimistic, predicting humans would land on Mars in 2021 and 'have some unpleasant surprises'.

Clarke was a big man who laughed easily and retained the distinctive accent of his native Somerset - despite living in Sri Lanka since the 1950s. Balding and bespectacled, he had considerable presence. He looked every inch a space-age visionary, science boffin and English eccentric.

In recent years, his health deteriorated, and his astonishing memory started to fade. He tired easily, but never stopped working. Indeed, shortly before his death, he finished the manuscript for a final novel, The Last Theorem. His enthusiasm was still infectious. He talked optimistically about the future awaiting man in space.

'The golden age of space is only just beginning,' he said. Sometimes his voice shook, and his eyes looked sad as he recalled great contemporaries now dead. Many had been friends. They included the outstanding science fiction writers, American Robert A. Heinlein and Russian-born Isaac Asimov, who, along with Clarke, had been regarded as the 'Big Three' of the genre for decades.

The late astrophysicist Carl Sagan had also been close. Clarke's writing had helped ignite the young Sagan's passion for science. Other friends had included the poet Allen Ginsberg and acclaimed film director Stanley Kubrick. It was Kubrick who had taken a brilliant Clarke short story, The Sentinel, and used it as the basis for the iconic science fiction film 2001: A Space Odyssey in 1968. The two co-wrote the film's screenplay and its cult popularity made both famous.

His spacious Colombo home was equipped with a large telescope, which let Clarke photograph the moon. The house also had a satellite dish - a gift from the Indian government in 1975. The writer's office bore testimony to a fascinating life.

On the walls were honorary degrees and awards from universities, science academies and Nasa. An impressive bookcase was devoted to Clarke's works - he had authored more than 80 titles. A framed newspaper front page dominated the room. It recorded man's historic landing on the moon on July 16, 1969.

As a young man, Clarke had predicted a successful lunar mission in his lifetime. The claim had initially been rubbished. But, as with many of his predictions, he was right.

It would be wrong to think of Clarke as a man with his head in the stars. He was keenly interested in contemporary problems, including protecting the environment. Indeed, he was passionate about alternative sources of energy. He was also an advocate of cold fusion - the generation of heat through fusion of molecules at normal temperature.

Long before it became fashionable, he had argued that the age of fossil fuels was ending and more environmentally friendly alternatives had to be found.

Another interest was robot technology. Like Asimov, Clarke had offered readers a fascinating glimpse into a future robot age. One of the most memorable protagonists in 2001 was the Hal 9000 computer, an intelligent, talking - and not so benign - machine. Clarke said at the time that the day of such machines was coming.

'Hal is certainly possible now ... There will undoubtedly be machines at least as intelligent as man by around 2020.'

Clarke had predicted opportunities for space travel would be unlimited. 'I have no doubt that space colonies will be built ... a spaceship which can reach the moon at all would require less time for the journey than a stagecoach once took to travel the length of England. When the atomic drive is reasonably efficient, the nearer planets would be only a few weeks from Earth, and so will seem scarcely more remote, than are the antipodes today.'

Arthur Charles Clarke was born on December 16, 1917, the son of a farmer. As a boy in England, he developed a love of science and science fiction, which was flowering - mainly due to H.G. Wells, whose War of the Worlds and The Time Machine captivated readers. 'H.G. Wells' accomplishments were extraordinary,' Clarke said. 'He wrote about everything - machines, space and time.'

During the second world war, Clarke was a flight lieutenant and radar instructor with the Royal Air Force, and even at that stage made a notable contribution to science. In 1945, he outlined ideas behind communications satellites.

After the war, he went to King's College in London, where he received a bachelor's of science in physics and mathematics. He received an excellent education - in both arts and science - something he said too few students received today.

'We need better schools and teachers today. I hope it will not be too late for the United States to undo the damage wrought on its educational system by fundamentalist fanatics, creationist crazies and New Age nitwits. Such people are a greater menace to an open society than the paper bear communism ever was.'

In the late 1940s, Clarke's writing career began to take off with the publication of his 'hard' fact-based stories, which were to win him international acclaim. His first science fiction story was Loophole, which appeared in the magazine Astounding in 1946, and his novel Against the Fall of Night was published in Startling Stories in 1948. Clarke's first science fiction novel was Prelude to Space, published in 1951.

In 1954, Clarke moved to Sri Lanka, captivated by the island's beauty. It was also ideal for indulging his passion for diving. In the 1950s, he and a friend, Mike Wilson, found a 250-year-old wreck off Sri Lanka's Great Basses Reef. Clarke said scuba diving was similar to the feeling of weightlessness that astronauts experienced in space. Despite suffering from polio syndrome since the 1960s, he said: 'I'm perfectly operational underwater.'

In The View From Serendip (1977), Clarke wrote that Sri Lanka 'is a small universe; it contains as many variations of culture, scenery, and climate as some countries a dozen times its size'.

Throughout the 1960s and 1970s, Clarke maintained a close interest with the US space programme. He co-broadcast the Apollo 11, 12 and 15 missions. He produced a 13-part television series Arthur C. Clarke's Mysterious World in 1981 and Arthur C. Clarke's World of Strange Powers in 1984.

At the end of his life, Clarke remained optimistic. 'Over the next 50 years, thousands of people will travel to Earth orbit and then to the moon and beyond. Space travel and space tourism will one day become almost as commonplace as flying to exotic destinations on our own planet.'