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I've made my first novel, Ventus, available as a free download, as well as excerpts from two of the Virga books.  I am looking forward to putting up a number of short stories in the near future.

Complete novel:  Ventus


To celebrate the August, 2007 publication of Queen of Candesce, I decided to re-release my first novel as an eBook. You can download it from this page. Ventus was first published by Tor Books in 2000, and and you can still buy it; to everyone who would just like to sample my work, I hope you enjoy this version.

I've released this book under a Creative Commons license, which means you can read it and distribute it freely, but not make derivative works or sell it.

Book Excerpts:  Sun of Suns and Pirate Sun

I've made large tracts of these two Virga books available.  If you want to find out what the Virga universe is all about, you can check it out here:

Major Foresight Project:  Crisis in Zefra

In spring 2005, the Directorate of Land Strategic Concepts of National Defense Canada (that is to say, the army) hired me to write a dramatized future military scenario.  The book-length work, Crisis in Zefra, was set in a mythical African city-state, about 20 years in the future, and concerned a group of Canadian peacekeepers who are trying to ready the city for its first democratic vote while fighting an insurgency.  The project ran to 27,000 words and was published by the army as a bound paperback book.

If you'd like to read Crisis in Zefra, you can download it in PDF form.

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The missing research program for space colonization

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We've spent decades studying the effects of zero-gravity on the human body, when we should have been studying something else

As the Shuttle age draws to a close, there seems to be revived discussion in the media about where manned spaceflight is headed next.  The short answer is, of course, "nowhere," but we still see enthusiastic articles about returning to the moon, or visiting Mars.  The problem is, if you look at budgets and research programs, it quickly becomes clear that nobody's really interested in either of those objectives.

For instance, if NASA were actually interested in putting people on, say, Mars, for extended periods--or on the moon or indeed anywhere but low Earth orbit--they would logically have long ago embarked on a research program to learn what the biological effects of Martian or lunar gravity are.  Instead, they've invested decades and billions into learning how humans react to zero gravity--an almost useless scientific endeavor, because the clear lesson from the start of that program was that living in freefall is a bad idea.  Conclusion:  whenever people are going to spend more than a few weeks in orbit, provide them with artificial gravity in the form of a rotating spacecraft.  There's no reason not to; the technology involved in spinning things around is not actually rocket science.

No amount of data about how the human body reacts to zero-G is going to answer the important question, which is:  how does the human body react to extended periods under fractional gravity--like the moon's 1/6 G or Mars's .38 G?  If there's a potential show-stopper to colonizing other worlds, it's going to be how our physiology responds to fractional gravity, not zero gravity.

At what gravitational level does osteoporosis start in human bones?  What's the minimum level for maintenance of cardiovascular health?  At what level do embryonic and infant development begin to suffer?  Maybe these questions can be tentatively answered from studies in zero-G, but any conclusions reached that way need to be empirically confirmed.  In other words, what manned spaceflight needs as its next step is a variable-gravity research station.  The ISS is useless for learning what we really need to know; what's needed is a very simple, rotating station whose gravity can be tuned up or down to simulate life on worlds ranging from Mercury to the moon to Mars, or Ganymede or Titan.

It's pretty clear that NASA's not interested in doing such research.  There is an opportunity here, however, for the private sector to step in.  Once Robert Bigelow's inflatable space stations come onto the market, someone could attach one to a spent booster stage and rotate the ensemble.  They could then do the necessary experiments and sell the results to NASA or, say, the Chinese, who are sure to be interested.

I'm going to add this item to my list of things to do if I had a billion dollars.    But as long as the world's space agencies lack a variable-gravity station, you can be sure they're not actually serious about establishing a human presence on our neighboring worlds.

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Good point

Posted by Adam Crowl at Aug 14, 2009 07:17 AM
Hi Karl

Excellent point. All the zero-gee mucking about is just stupid anyway since the old "1 rpm" figures used by O'Neill and co. are incorrect. A rotating habitat can be a lot smaller than a Stanford Torus. Benford & Zebrowski quoted 6-10 rpm as rotation rates people can adapt to, which makes partial gee stations even smaller. A 10 metre radius centrifuge gives a Mars 'gee' at 6 rpm and it's just 4 metres for Moon/Ganymede/Titan/Europa/Callisto 'gee'. Smaller bodies are half-Moon 'gee' or less. Not zero, but not far off.

Weren't always zero-gee obsessed at NASA. The old pre-Skylab MORL space station had a centrifuge and a few Saturn-V launched 'pop-up' stations were wheel-based. Shame they never flew, but the microelectronics revolution took away most of the need for human crews on satellites...
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The Virga Series

(Sun of Suns and Queen of Candesce are combined in Cities of the Air)

Available in Trade paperback May 5, 2012:


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    Lady of Mazes

    “The most thought-provoking and interesting work of hard SF that I've read in the past year."
    —Charles Stross

    "With paradigm shifts one inside another like a set of Russian dolls, this splendid novel propagates into a demolition derby of Big Ideas. Required post-human reading.”
    —Scott Westerfeld, author of The Risen Empire

    “An astonishing saga. One helluva read!”
    —Charles Harness

    “Karl Schroeder has always had a knack for intelligent and provocative thought experiments disguised as space opera. Now he ups the ante with a fascinating riff on consensual [and conflicting] realities. Lady of Mazes contains more cool ideas than Ventus and Permanence combined.”
    —Peter Watts