Rocheworld

Rob McLaughlin
Space Physics Essay

In Rocheworld, Robert L. Forward put a lot of thought into getting the physics of the story right. A large amount of the story takes place in outer space, where the gravity is much different than it is on Earth. There are a couple of specific points in the book where Forward explains in detail the physics of a situation. Not all the points he is trying to make really has a huge affect on the story, but it provides a certain attachment to what the characters are experiencing, and also has the opportunity to educate the readers on what being in space would be like. When the crew is on Mercury, they are educated quite extensively on the gravitational forces that are happening there. First, is the placement
In free-fall, he could let go of the fixture, and he would remain next to the light fixture on the ceiling, because there is no gravity to pull him back down to the ground. When he first let go of the fixture it seemed like that’s exactly what happened, but then after a couple seconds it became clear that he was very slowly floating back down to the ground. The Chief explained that, “Mercury Center is not in orbit around Mercury, but it is floating at some point eighty thousand kilometers above the surface of the planet. The pull of Mercury is counteracted by the large ring-sail that you saw as you arrived…” What he is trying to explain is that at that distance from the surface of Mercury, the gravitational force is 1/3000th of Earth. The entire station is actually being pulled down towards Mercury. They are able to counteract the gravitational force of Mercury, by the humungous circular light-sail that the station has. The light sail at the station works the same way that the Prometheus is propelled through space. While the Prometheus uses laser light from the station to be propelled through the stars, the Laser Station has a large light-sail ring that captures the light power from the sun, which pushes the station
As the Prometheus makes its way to Barnard, propelled by the laser light beam, the ship has no ability to create artificial gravity, so the crew is in free-fall for the duration. Living in free-fall is obviously very different from living in the gravity we have on Earth, and the ship has been fitted with some tricks to make life a bit easier on the ship. One of the most interesting steps taken was to cover a lot of the ship in Velcro. The ground, couches, and beds have been covered in Velcro, along with the bottoms of the crew’s shoes and clothes, so they can stick to the ground and other surfaces, instead of constantly floating around. As the Prometheus is propelled forward, there is a bit of gravity at times, not always, from the linear acceleration from the laser beam. As the ship accelerates, there is a minimal, although apparent, affect of G forces on the crew temporarily. These forces will not remain though, as the crew “catches up” with the momentum of the ship, and returns to total free-fall. There is a part in the book while the crew is under the effect of No-Die, that they play a childish game using centrifugal force. In the circular room outside crew quarters, they played “Around the World, Don’t Fall In”. They could start running along the walls in the room, and eventually pick up enough speed to create up to 1/3 G forces to “stick” to the wall so they