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Slingshot to Pluto

We've been waiting for a long time. Finally we're on the way. But there are no "direct" flights to Pluto - the only way to get there is to first swing by Jupiter.

Pluto is a small, mysterious world, deep in the cold, dark recesses of the distant outer solar system. It was named a planet when it was discovered in 1930, but that designation has been in dispute for some years now. The issue was settled in August of 2006, when the International Astronomical Union reclassified Pluto as a dwarf planet.

The reclassification is a result of new and better information that, in turn, came from improved technology and observing methods. It's a beautiful example of the scientific process in action. Science is not a static body of facts, but an active process subject to constant revision. Theories are tried and tested. If they fail they are discarded. Old information sometimes turns out to be inadequate. New information can change our understanding of the world (and universe) around us. It helps to remember the history of astronomy is a history of changing worldviews as a result of new and better data.

And we want the science process to continue. Refining the classification of solar system objects does not change the nature of Pluto. It is still a small, rock and ice body far away from the Sun. We don't know a lot about Pluto. We want to lessen the mystery and learn more about this distant world. In the process we'll learn more about the rest of the solar system and our history in it.

Figure 1. The inclination of Pluto's orbit is one factor that sets it apart from the eight major planets.

Figure 2. New Horizons makes its close swing through the Jovian system.

Figure 3. When you look at Jupiter this month, you're also looking towards the New Horizons space probe.

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