This story was updated at 7:00 p.m. ET.
Editor's note: SPACE.com received an overwhelming response to Arthur C. Clarke?s passing. Click here to read more reactions from scientists, writers and other luminaries.
As news of Arthur C. Clarke's death spread through communities of scientists, writers and science fiction fans, many people shared their memories of how the visionary writer, inventor and futurist inspired and influenced them.
Clarke is famous for his book, "2001: A Space Odyssey" (he also co-wrote the screenplay for the movie), for coming up with the idea for the communications satellite and for predicting space travel long before humans left Earth.
"I think the passing of Arthur C. Clarke is really epical," said Alan Stern, associate administrator of NASA's Science Mission Directorate. "There is no one of his caliber or vision on the scene today ? Clarke's contribution was to motivate people to go after careers because they wanted to help shape a certain kind of future, to be at the beginning of something of millennial importance."
Stern said Clarke's legacy at NASA and in the space exploration community was particularly significant.
"For my generation, the children of Apollo, Clarke's writings were hugely and deeply inspirational," Stern told SPACE.com. "He was not just a technically competent writer of science fiction, science fact and futurism, but he was incredibly optimistic. I have had many emails in the last 18 hours, from friends of mine, from childhood, graduate school, >adulthood. It's amazing to me how many say the same thing: 'I wouldn't be in this line of work if it weren't for Arthur Clarke.' People across the world, especially the backbone of American aerospace exploration and space science, were inspired by Clarke's writings at one stage or another in their youth."
Clarke had a profound impact on technology and invention. His idea for the communications satellite has affected the whole planet.
"Arthur was not only a major figure in the first baby steps in humans' exploration of space, but a major figure in the building up of our planet as an interconnected organism," said writer Ann Druyan, widow of science popularizer Carl Sagan. "He was someone really significant."
Druyan said she met Clarke many times over the decades that he and Sagan were friends, as well as after Sagan's death.
"He was not only a great technical mind, but of course he had a powerful imagination, which influenced every one of us," Druyan said. "If we use anything based on a communications satellite then we definitely owe Arthur a huge debt. In my mind, '2001' remains the greatest sci-fi movie ever made. In many ways today it seems more futuristic than movies made 30 years later."
Many people have wondered how Clarke was able to predict so many elements of the future before they unfolded in reality.
"I think it was partially because his mother was a radio telephone operator," Druyan said. "So here he is as a young person growing up in the early part of the 20th century, at a moment where electronic communication was in its fledgling earliest stages, and he is a guy who has an exceptional imagination. So it was the perfect recipe for a child with Arthur's talents to go in that direction. The modesty of his background is yet another reason why it's so important to educate everybody, because you never know where the next Arthur C. Clarke or Carl Sagan could be."
Druyan said her friend will be remembered long after his death.
"Arthur had a great life," she said. "I don?t really feel sadness because I think he had a full measure of life and he used it to the utmost. We are better for [his life]."
End of an era
Clarke also profoundly affected his fellow science fiction authors.
"Arthur C. Clarke was one of the giants of science fiction; impossible to ignore, looming over all of us who have come since," said Charles Stross, author of the novels "Saturn's Children" and "Halting State." "He introduced many of us to science fiction for the first time ? He managed, somehow, to combine visions grounded in an understanding of science and engineering with a numinous sense of awe at the scale and beauty of the cosmos in a manner that is all too rare."
With Clarke's death, an important epoch in the world of science fiction is over, Stross said.
"All of us come to an end eventually, and at 90 years of age Sir Arthur had decent innings," he said. "But I'm still saddened: Along with Isaac Asimov and Robert Heinlein, he pretty much defined science fiction for those of us of a certain age, and news of his death signals the end of an era, far more than the end of one man."
Many writers remember the first Clarke book they read, and the profound effects his work had on them.
"My friends and I read Clarke and talked about his fiction with the awe of rabbinical students falling in love with Torah and Talmud," said Orson Scott Card, author of many science fiction novels, including "Ender's Game." "Inarticulate with youth, we would say things like, 'Wasn?t it cool when ...' But we were responding to the experience of religious awe, which Arthur C. Clarke?s fiction inspired in us."
Although Clarke is no longer with us, his work will live on, Card said.
"His books have not died," Card told SPACE.com. "They are still alive. As long as we pass them on to the young, open-minded readers who are the natural audience for science fiction, they will continue to inspire and move new generations. The technologies that he explained or forecast will or have become pass?; but the deep issues his fiction addresses will live on, and so will our hunger for books like his."
A writer's writer
Not only did Clarke impact the sweep of human history with his ideas, but he had a very direct effect on the lives of many.
"When I met my wife, just shy of fifty years ago, I gave her one book to read, to see whether we could get along — Arthur Clarke's collection of stories, 'Expedition to Earth,'" said Joe Haldeman, author of "The Accidental Time Machine." "She did like it, and we're still going together."
Plus, he was a great smoking companion.
"I had the great pleasure of watching a couple of Apollo launches with Arthur," Halderman said. "For most of those launches, all of us science fiction writers got together at the house of Joe Green, a writer who worked for NASA. Arthur and I were smokers then, and so were banished to the back porch together. He was a wonderful conversationalist, >which I hope made up for the fact that I was tongue-tied, thrust into isolation with an idol of my youth. He was a writer's writer, and a humane and brilliant man. He will be missed, and never replaced."
Creating the future
Clarke inspired many young people to pursue science, and shaped the way many scientists approach their work.
"He affected how I thought about what I was doing," said Ed Stone, director of the Space Radiation Laboratory at Caltech and project scientist for nine satellite missions, including Voyager. "What he did was take what was happening in science and extrapolate it in a realistic way into way in the future. Since that's what science and engineering and technology are trying to do, to create a new future, it was very interesting to get his ideas of what that future might look like."
He helped to make science important and understandable to the public.
"One of his main legacies is his really firm belief that science and technology is a defining feature of human evolution," Stone said. "And I of course believe that myself. So he was a very effective writer in capturing the idea of how important science and technology are to human evolution."
Click here to read additional comments from scientists, writers and other luminaries about Arthur C. Clarke's passing.
Staff Writer Dave Mosher contributed reporting to this story.
- Video: Arthur C. Clarke ? To Plan For A Century
- IMAGES: 2001: A Space Odyssey
- The Essential Arthur C. Clarke Library