I don't usually pay too much attention to things like that, but I found the use of underlining to denote thoughts and emphasis distracting. I was also distracted by the use of frequent one sentence paragraphs near the beginning.

Overall, this seemed pretty strong. The descriptions were sufficient without slowing down the pace too much, and the dialogue seemed pretty natural. I also like that Tatiana can't understand the colonists' dialect, though I would have been more pleased to see an example of it.

I have to say Tatiana seems pretty unsympathetic as a protagonist though. She comes off as somewhat bigoted and dimwitted for someone with such a high IQ (although I suppose that isn't unrealistic. I've known plenty of geniuses that were none too smart at times). While the style was appealing enough to keep me reading to the end, I didn't find her likeable enough to particularly care what happens to her.