Happy Birthday, America

Let’s celebrate the fourth of July with some stars and stripes. In 2004, SpaceShipOne made the first private trip into space, later winning the $10 million Ansari X Prize. Now hanging in the Milestones of Flight gallery at the National Air and Space Museum, SpaceShipOne, along with the White Knight mothership that it launched from, were developed by Mojave Aerospace Ventures, a joint project between Burt Rutan’s Scaled Composites and Paul Allen.

Here are four little known facts about SpaceShipOne, as discussed by Dr. Valerie Neal, curator of Human Spaceflight at the Museum, during an “Ask an Expert” event for the spacecraft earlier this week.

1. When SpaceShipOne was gifted to the Museum, the design team signed the exhaust. The bright silver signatures can be seen from the floor of the Milestones of Flight gallery.

2. On SpaceShipOne’s first flight, the exhaust buckled due to the change in pressure, leaving a dent on the underside of the aircraft. The exhaust was fixed for subsequent flights, but the team intentionally dented the exhaust again to replicate its original state before giving it to the Museum.

3. The hybrid rocket engine in SpaceShipOne combined liquid and solid propellant, with rubber as the fuel and nitrous oxide as the oxidizer. These stable and nontoxic propellants gave credibility to the idea of feasible space tourism.

4. The successor to SpaceShipOne is, of course, SpaceShipTwo, now owned by Virgin Galactic. Sir Richard Branson says he plans to be a passenger, along with his family, on SpaceShipTwo‘s inaugural flight to space later in 2014.