For generations, science fiction writers have designed unreal planets according to scientific principles, often with fascinating results. Hal Clement and Poul Anderson stand out as modern masters of this discipline. Clement created a prototypical alien world, the massively oblate planet Mesklin in Mission of Gravity, along with its centipede-like intelligent inhabitants. Poul Anderson fashioned many diverse planets both in his stories and for the marvelous CONTACT conferences, providing challenging environments for suitably alien beings with whom students would then devise means of communication and cooperation.

Only in the last couple of decades has astronomy caught up with imagination and even begun to exceed it — at least where the peculiarity of real planets is concerned. As of 2010, the Extrasolar Planets Encyclopedia has confirmed 500 planets outside of our solar system, circling other stars — and so it is high time for “Journey to the Exoplanets,” an iPad-compatible app with primary text by Edward Bell and artwork by Ron Miller, published by Scientific American, Farrar, Straus and Giroux, and Brandwidth.

[Make your own planet]

This year marks the 50^th anniversary of the publication of Poul Anderson’s The High Crusade in the pages of Astounding magazine (later to be known as Analog that very year). In celebration, Baen Books is releasing an anniversary paperback edition on Tuesday, September 7^th, with appreciations from some of science fiction’s greatest names.

Tor.com will be posting these appreciations throughout Monday and Tuesday of this week, courtesy of Baen Books. These appreciations originally appeared at WebScription, where you can also sample the first few chapters of The High Crusade.

At the age of eleven or twelve, I picked up a book by Poul Anderson called The High Crusade. I was already a fan, having worked my way through a shelf-full of science fiction anthologies, best-of-the-year compilations from the 1950s at my local Navy base library in Kodiak, Alaska. Nearly all the anthologies contained stories by Poul.

But “The High Crusade” was something else again—a lively, sharp-witted reversal of science fiction stereotypes, as well as a magnificent adventure, full of larger-than-life characters.

[Read more]

It’s almost impossible to convey the mood of the late sixties—such a mess of politics and war and confusion over whether the Cold War was going our way or not—but for a brief moment, the world was united around a single moment of utter awe...

I was seventeen years old, squatting on the living room carpet in our family’s College Avenue apartment in San Diego. I was already a published writer and a fan and had been working up my expectations for this moment for years—practicing for the occasion by watching “2001: A Space Odyssey” many, many times—and now it was here. The grainy but live video footage from the moon was unprecedented—we truly were living in a science fiction world, but things were turning out as no sf writer had predicted—with hundreds of millions of people watching. The first night on the moon—it would take years to comprehend, but my quick assessment at the time has stuck with me to this day. “For the first time in four billion years of Earth history, living creatures have stepped off the surface of our world and set foot on another.”

Walter Cronkite and Arthur C. Clarke and Robert Heinlein provided late-night commentary, the sort of visionary and expert testimony about a world-shaking event that is tough to imagine being broadcast today. Ray Bradbury fled from the Dick Cavett Show green room when he realized he has being upstaged on this night of nights by a pop singer. Emotions were running incredibly high. But for me and my parents and for my high school and college friends, this was an apotheosis. The future was here.

We’ve had many terrific moments since—and quite a few terrible moments. But there was nothing like that one. It was a different time, almost a different civilization. I’d give a lot to start from that point again and see what we could do different, how we could avoid bitter mistakes... But hell, we’re human, we did it, we were magnificent, and we’ll do it again.

This time, better—and for good.

Greg Bear is an American science fiction writer, perhaps best known for the novels Blood Music, Eon, and The Forge of God. He has published over thirty novels and received two Hugos and five Nebulas.