15 June 2015

Is Pluto a Planet?


In the past, I know I've been adamant to say that Pluto is not a planet. You can read them again here, here, and here. However, I've thought about things and may be coming around to categorizing Pluto as a planet.


Before, I had always said that there are two types of planets: terrestrial planets, like Earth, and Jovian planets, like Jupiter. But what if we redefined a planet to have a third type: dwarf planets. These are bodies in the solar system that are too large to be asteroids or comets but are not necessarily big enough to have swept all the smaller bodies from its orbit (meaning it could have co-orbital bodies), have densities somewhere between Jovian planets and terrestrial planets, and can be found anywhere in the solar system.


I did discuss dwarf planets in more detail in a previous post, when discussing Pluto (see first link above), so I may have unwittingly decided already that Pluto is a planet. In fact, if we make Pluto a planet again (which probably will happen sooner rather than later), we will also have add a few more planets to our solar system.
Trans-Neptunian Objects (objects orbiting the Sun outside of Neptune's orbit)
Image Credit:

Eris and Makemake will definitely be added. Haumea, Sedna, and 2007 OR10 may as well. It all depends on where the lower limit of a dwarf planet's size will be if the IAU determines that.

This is what I love about science. It's a fluid subject that can easily change based on new information. I've changed my mind about Pluto (for now), and there may be other things I might change my mind about.

No comments:

Post a Comment