Helen Sharman

During launch, the outside of the rocket is covered in a protective fairing, so we couldn't see outside, but as soon as that was jettisoned, my first view of the earth was over the Pacific Ocean, which was this wonderful deep blue, with clouds just over the top, and sunlight streaming in through the window.

The historical novelist has to consider what has actually happened, while the SF writer is dealing in possibilities, but they are both in the business of imagining a world unlike our own and yet connected to it.