Is Pluto even a planet?

According to arecent YouGov poll,35% of Americans think Pluto is not a planet.

It’s something else, according to them.

But they are all wrongkind of.

To get to the bottom of Pluto’s planet status, I tracked down planetary scientistDr.

The case for Pluto’s planet-ness

According to Dr. Grundy, Plutoisa planet.

“Pluto’s got everything I like in a planet, in spades.

It’s got a satellite system.

It’s got atmosphere with interesting weather patterns.

It’s got very complicated seasonal cycles.

It’s got all kinds of active geology going on… it’s got everything you want.”

So Pluto is a planet.

The case against Pluto’s planet-ness

According toThe International Astronomical Union, Pluto is not a planet.

The IAU shook the world in 2006 when it took Pluto’s status as a planet away.

Have enough mass for your own gravity to pull you into a nearly round shape.

Have cleared the area around your orbit of other significant objects.

Like my friend Dave, Pluto has only met two of these criteria.

That third one is too much for Pluto.

They’d all have to be call “planets” if the older definition of the word was used.

So the IAU punted.

“They had a moment of a crisis of strength of will,” Grundy said.

According to many scientists, this was a mistake.

According to Grundy, the more planets, the better.

Is Pluto actuallytwoplanets?

How about this to blow your mind: Pluto istwoplanets.

Pluto’s largest moon, Charon, is almost half the size of Pluto.

“I would consider Charon big enough to be a planet,” Grundy said.

“It has geology and all kinds of processes going on.

What more could you ask for?”

“It really just depends on your focus.”

No matter what we call Pluto, it’ll still be out there, doing its Pluto thing.

“Textbook authors seem to always seek authority.

They want a definitive answer, because they don’t want to be wrong.

But that’s not really the way nature works.

Nature is very messy and muddy,” Grundy said.

“We used to categorize whales with other fishes because they lived in the ocean.

But why do we care more about phylogenetic origins than we care about location?