Was it only yesterday that the future was a real place? Earth was the alien planet, off-world exploration stopped short at a few orbital sex shops and high-rolling shopping malls. We were alone in the universe, contemplating otherness in the mirror. The only galaxies to be explored were in inner space, the only theatres of adventure and wild fantasy left to us were in the faux wonderlands of virtual reality. We were talking about the forseeable, we were attempting to prove the possibility of everything we could imagine. Isn't that the way it was? The wheel turns (or the helix twists) and here we are again on the bridge of the Starship Enterprise. Habitable planets are scattered like daisies for the plucking, aliens come in any shape or form (so long as you can do it with face-makeup); and the most important scientific decision an sf writer has to make is whether to type the letters on the warp-drive button ‘ftl’ or FTL.

It is difficult not to exaggerate when making sweeping statements. I would hesitate to claim that ‘nobody is doing realist extrapolation anymore’. One of the major sf events of the last year, Stan Robinson's Red Mars (though purest fantasy when measured up against the shrinking budget for Freedom, or any other boring, economic measures) seems to be bucking my trend. On the other hand, unreal sf has certainly made a comeback. Space-opera is no longer a joke. Or if it is, it's a very good one. Colin Greenland's splendid Take Back Plenty has replaced the canals on Mars and the swamps of Venus. Colourful adventure on alien planets (with or without actual furry or tentacled aliens) is once more in fashion. Romantic classics like Roger Zelazny's Lord of Light, long relegated to the fringes of fantasy, may have to be reassessed. In the Nineties it is again possible, almost necessary, to write important sf about the kind of future that doesn't have a clue how we got there from here.

John Barnes's A Million Open Doors is set in much the same retrofitted golden-age as Sheri Tepper's planet-hopping series (Grass, The Gate into Women's Country ; Raising the Stones ; Sideshow).