Pluto: Is it a planet, comet or dwarf planet?

The debate has continued about what exactly Pluto is since its 2006 official relegation from a planet to a dwarf planet by the International Astronomical Union.

Now NASA’s New Horizons mission has thrown in more food for thought with new findings that reveal that Pluto may act more like a planet than experts thought. Observations in solar winds and the way in which they interact with atmospheres has led to the conclusion that Pluto acts in a new, unique way not ever observed before.

According to Discovery News, scientists believed that Pluto had a more comet-like interaction with solar winds however, new research has shown that Pluto’s synergy with solar winds are actually a lot more diverse, making Pluto unique in its own right acting neither comet-like or planet-like.

Solar wind is a large amount of charged particles that interacts with anything that stands in its path. The way it interacts with comets and planets (including dwarf planets) are all different with comets causing a slowing down of the solar winds and larger planets causing abrupt diversions.

What the team of researchers found was that Pluto’s interactions with the solar wind were neither that like a comet or a planet, leading to a conclusion that it is a special hybrid of the two.

Lead author of the study, Prof. David J. McComas of Princeton University, says that “this is a type of interaction we’ve never seen before anywhere in our solar system, the results are astonishing.”

The research also led to the discovery that Pluto’s atmosphere also contains neutral particles that are converted to charged ions and released back into space, much like that on Earth.

New Horizons principal investigator Alan Stern, says, “these results speak to the power of exploration. Once again we’ve gone to a new kind of place and found ourselves discovering entirely new kinds of expressions in nature. Many people were surprised by Pluto’s complex geology and atmosphere. This paper shows there’s even more that’s surprising there, including its atmosphere-solar wind interaction.”

The study was published in Journal of Geophysical Research: Space Physics.