Changes

Finally, the astronauts realize the significance of the stainless-steel shrapnel with which Bob had been wounded in the initial explosion. None of the ship's systems was made of stainless steel—in fact, the lack of any material but plastic was a source of great frustration to Valkerie when she first attempted to seal the hull breach. Valkerie and Lex realize that the stainless steel must have come from a bacterial culture vial that Josh Bennett had received from a former girlfriend in [[Antarctica]]—and that the vial contained a radiation-resistant bacterium, the same one that in fact had contaminated some of the ship's systems after the explosion. Now the astronauts realize what has happened to them: Josh Bennett, fearing cancellation of Project Ares and the disbanding of NASA, sought to "seed" a radio-resistant bacterium on Mars for the astronauts to "discover." To accomplish this, he did plant a bomb on board, designed to detonate with the deployment of the aerobrakes. But the damage to the habitat on the rocky launch ultimately caused the bomb to detonate in transit. This also explains Josh's brittle emotional state: he realizes that his attempt to give the astronauts something to discover very nearly killed them instead. Bob ultimately tells Josh that Valkerie has figured it out, and that they all forgive him for what he did, knowing as they do that he never meant them any harm.

Finally, the astronauts realize the significance of the stainless-steel shrapnel with which Bob had been wounded in the initial explosion. None of the ship's systems was made of stainless steel—in fact, the lack of any material but plastic was a source of great frustration to Valkerie when she first attempted to seal the hull breach. Valkerie and Lex realize that the stainless steel must have come from a bacterial culture vial that Josh Bennett had received from a former girlfriend in [[Antarctica]]—and that the vial contained a radiation-resistant bacterium, the same one that in fact had contaminated some of the ship's systems after the explosion. Now the astronauts realize what has happened to them: Josh Bennett, fearing cancellation of Project Ares and the disbanding of NASA, sought to "seed" a radio-resistant bacterium on Mars for the astronauts to "discover." To accomplish this, he did plant a bomb on board, designed to detonate with the deployment of the aerobrakes. But the damage to the habitat on the rocky launch ultimately caused the bomb to detonate in transit. This also explains Josh's brittle emotional state: he realizes that his attempt to give the astronauts something to discover very nearly killed them instead. Bob ultimately tells Josh that Valkerie has figured it out, and that they all forgive him for what he did, knowing as they do that he never meant them any harm.

The last scene is a set-up for the sequel: Bob, who is now enamored of Valkerie, proposes marriage to her before a world-wide six-billion-strong television audience that has tuned into watch "the first two astronauts to walk on Mars."

The last scene is a set-up for the sequel: Bob, who is now enamored of Valkerie, proposes marriage to her before a worldwide six-billion-strong television audience that has tuned into watch "the first two astronauts to walk on Mars."

{{endspoiler}}

{{endspoiler}}