THE MARS GIRL (Joe Haldeman)

Carmen Dula was just like any other girl. Or she used to be, before she spent six months on the spacecraft, John Carter, as part of the first nine families to settle on Mars.

Just like any other teenager she was curious about her new home—who wouldn't be?—but she did her schoolwork, enjoyed time with her friends, and she started to explore the red planet with the supervision of her guide and friend, Paul Santos; always within the rules set by the colony.

Yet the Administrator, Dargo Solingen, seemed to have it out for her. She had no idea why, but she was blamed for every slight; every transgression. Until one day she had enough.

At night fall, Carmen donned a biosuit and ventured outside on her own—during curfew, while her outside privileges had been suspended. She didn't have a set goal. All she knew is that she wanted to explore...

What happened next was beyond her most wildest dreams. But how can she prove what she saw that night, when almost everyone assumes she is lying? 

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AS BIG AS THE RITZ (Gregory Benford)

Clayton Donnor grew up in a hard-working mining asteroid community, so when he went to Earth to study at UCLA, he thought all his dreams had come true. Earth was gaudy, effervescent and, above all, it was fun.

Majoring in Comparative Astrophysics, and Minoring in Analytic Economic Morality, Clayton's aspirations were large. But he had no idea what would be in store for him when he first met Sylvia Rolland, and she invited him home to meet her father.

For Dr. Norman Rollan had created the elusive Brotherworld, a manufactured Hoop world a few kilometres thick, that circled around the Vortex of a black hole twenty kilometres away.

Why did Dr. Rollan not allow any Astrophysicists to visit? What were his colony of genetically- perfect clones hiding? Clayton was determined to find out...