Friday, July 31, 2009


Ever wonder what those little rockets that move spacecraft around look like? Here's a pic of the RCS, or Reaction Control System, from Apollo (this one on the Apollo Service Module). The RCS system can propel the craft in a fore-and-aft direction, side-to-side, spin, or turn. In a pinch, it can also be used to deorbit with sufficient fuel. Each thruster had about 100 pounds of thrust, and was fueled by a mixture of nitrogen tetroxide and hydrazine. These two chemicals mixed in a hypergolic reaction, that is, they combusted without an ignition source. In fact, great care had to be taken when dealing with the hydrazine, as workers in the Grumman plant in New York discovered one winter. They were working with the volatile chemical, spilled some onto an early show, and watched it burst into massive, incendiary flame.

The RCS quad seen here is located in the Service Module exhibit at the Kansas Cosmosphere.

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Welcome to the Missions to the Moon book blog. This is a place to re-live the heady days of the Apollo and Soyuz lunar programs- perhaps the crowning achievements of the 20th Century. Many blog entries will include a new downloadable image or artifact from the space age- items rarely seen and not available in print. It's all in the spirit of my newest book, Missions to the Moon- to remember the great adventure of the Golden Age of space exploration, and ponder what wonders await us in space.

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