The debate on whether Pluto should still be considered a planet. Discover arguments, and scientific perspectives on this controversial topic.

Video of the day December 19th 2019


There once was a 9th planet in our solar system. Its name was Pluto, and it was a “fact” that it was a planet…until it wasn’t. Join us as we explore whether Pluto should still be a planet.

The Life and Times Of Pluto

Before we fully dive into why Pluto should STILL be a planet…we need to talk about the “Fakeout” that occurred for many decades. Meaning, the finding, “labeling” and then unlabeling of Pluto as a planet. Sound good? Cool.

So, like many objects in the sky itself, Pluto has been around for an undetermined amount of time, for the sake of argument let’s say billions of years. However, just like many objects in the sky, it wasn’t noticed by humanity for a very, VERY long time. In fact it wasn’t discovered until 1930 via Clyde Tombaugh.

Though to be clear, it wasn’t a “random” find like certain other things in the universe. Rather, in 1846, people who were observing Neptune noted that there were some “discrepancies” in the orbit of Neptune that suggest that there was another planet nearby that they didn’t know about. Fast forward to 1930 and at the Lowell Observatory in Flagstaff, Arizona, Tombaugh found Pluto. Mystery solved.

The irony was that after taking notes about Pluto in regards to its mass and gravity, it was found that there was no way it was affecting Neptune’s gravity in the way people believed it was at first. That didn’t matter though because further study of Neptune seemed to fix all the beliefs about the discrepancies.

Things only got better for Pluto when later on it appeared to have a moon orbiting it in the form of Charon. This was important because it meant that Pluto was big enough and had enough gravity to make something orbit it. A true classification of a planet.

For many decades, 6 in fact, Pluto was a happy member of the solar system. 9 planets orbiting 1 sun. Everything was great…until it wasn’t.

The Fall Of Pluto

Ok, so, what the heck went wrong? How did we go for decades thinking that Pluto was a planet and yet somehow…it’s not anymore? That would be because of the 1990’s (already a tumultuous period of history…), where scientists started to doubt that Pluto was a planet at all.

But how exactly does that happen? How does one decide that a planet is “not a planet”. Well in the case of Pluto, that would have to do with location. Specifically its location in regards to both Neptune, and a belt of asteroids known as the Kuiper belt. You see, these are a string of asteroids, at least 1500 at last count in 2014, more than likely many more now, and they’re held in place in part by Neptune’s gravity.

Why does that matter? Well, the Kuiper belt is just outside the space that Pluto is in. What’s more, based on imagery and estimates, some of these asteroids are not only planet-shaped, but they’re planet-sized. Some of them are even felt to be bigger than Pluto. So by that token, if there are asteroids in this belt that could be planets themselves…and they’re bigger and have more massive than Pluto, and have an orbit just like Pluto or close to it…why should Pluto be a planet?

This may sound like baseless accusations and such, but the scientific community had a different opinion on the matter. Mainly, they all started to wonder if Pluto honestly should be called a planet, or a “sub-planet” or a “minor planet”. Basically any adjective you can think of in order to make it clear that Pluto wasn’t a full planet. Things culminated in many ways back in 2000. The Rose Center for Earth and Space, home of the Hayden Planetarium, categorized Pluto in one of its exhibits as a sub-planet. “There is no scientific insight to be gained by counting planets,” said the Hayden Planetarium’s director, Neil de Grasse Tyson, “eight or nine — the numbers don’t matter.”

Tyson if you don’t know is a BIG deal in the scientific and astronomy community, so having him say it doesn’t matter if Pluto is considered a planet or not is a big blow.

Finally, on August 24, 2006, the International Astronomical Union’s meeting in Prague led to a vote as to whether Pluto should be named a planet or something lesser. They decided to make a new classification, “Dwarf Planet”, and thus Pluto was a true planet no more.

Should We Really Care If It’s A Planet Or Not?

Let’s be honest with ourselves, should we really care if Pluto isn’t a planet or not? Does it truly affect our lives if there are 8 or 9 planets or not? Does the Earth literally or figuratively respond to whether there is another planet revolving out there in space?

In a certain sense…probably not. Given that we only think about planets when we think about space, or have a job that involves space, it’s very fair to say that not having Pluto as a planet isn’t too big of a blow. And I would bet that some of you are only watching this video to see how passionately we try and defend Pluto’s status as a planet, which we’re getting to very soon.

But the point here isn’t that Pluto isn’t a planet anymore, it’s that it was a planet for 76 years, never had a problem with anyone, and then all of a sudden EVERYONE has a problem with Pluto! I mean, COME ON MAN!!!! What did Pluto ever do to you? So this is more than just a “number” as De Grasse Tyson stated, it’s about defending a planet that has been a part of a generations of people’s lives! So yeah, we should care about Pluto! We might be the only people that do!

Reason #1 – Why Change History And Schoolbooks?

I know on the surface this may seem like a petty reason, but let’s think about it in the grand scope of things. It’s true that history needs to be updated with actual facts as they come to light (evolution of humanity, migration across the world…Christopher Columbus…), and we know that history is often written by the “victors” so that means there are likely a lot of discrepancies that we are still teaching in schools today. To that end, it may seem fair to update something that is “false” in terms of a planet being something that it’s not.

Except…that’s not exactly what’s going on here, is it? Pluto wasn’t something that was magically created, it was found after scientific study, and it was found to have the traits of a planet. Mass, shape, orbit, not being a moon, and more. Then, some people decided to ask whether that itself was right or wrong, and a lot of debates got started, new rules were made, and now Pluto is suddenly not a planet.

That means that DECADES of astronomy talk was “incorrect” because some people decided to rewrite the rule book. Not the historical texts, not the information that stated Pluto was a planet, but the very definitions by which a planet is judged. All because they found some rocks in an asteroid belt that may rival Pluto in terms of its size and mass and such.

Doesn’t that seem petty to you? It sounded petty to a bunch of schoolkids when the word got spread around that Pluto might lose its planetary status. No, seriously, look it up! Kids across the United States petitioned and campaigned for Pluto to remain a planet because that’s what they had been taught, and they had no reason to not believe it to be true.

Plus, and I consider this one of the best reasons for keeping Pluto a planet, Pluto is listed as a planet in Schoolhouse Rock. The song Inter-Planet Janet listed out the whole solar system and states, “Pluto, little Pluto, is the farthest planet from our sun!”

If you can’t trust Schoolhouse Rock, who can you trust? That’s what I thought. 

Artist’s concept of the New Horizons spacecraft as it approaches Pluto and its largest moon, Charon, in July 2015.

Reason #2 – There Are Scientists Who Still Debate Pluto Is A Planet

While it’s true that the International Astronomical Union voted out Pluto as a planet and declared it to the world, and it’s nice that there is an “official” group that is bent on keeping space “accurate”, you do have to wonder just what it takes to be in that group, and who exactly gave them the power to say that something is “not a planet”. Or in this case is a “minor planet” or “dwarf planet” or whatever. It’s a bit curious, don’t you think?

I mean, just like a workers union doesn’t speak for everyone who works in the world or a country, should this union be held as the “definitive vote” for whether something is called something else amongst the stars? Many scientists would have to vote “no” on that front. In fact, there are many who are still fighting the good fight and stating that Pluto is still a planet, and that the International Astronomical Union was wrong to declare it as not one in the first place.

Like who? How about Philip T. Metzger, a man who has started up a new study that states that the Union bent the rules and thus Pluto is still a planet based on the actual stats and figures about Pluto and how it does indeed conform to the criteria of being a planet.

“Oh great,” you say, “one guy is leading a charge….rah-rah-rah!” Nice try, but he’s got more than himself on his side, the study that he made was co-authored by Mark V. Sykes of the Planetary Science Institute, Kirby Runyon of the Johns Hopkins University Applied Physics Laboratory (JHUAPL), and Alan Stern – the principal investigator of the New Horizons mission from the Southwestern Research Institute (SwRI).

So as you can see, there are some very big people thinking that Pluto is a planet. Furthermore, he has proof that the definition of a “planet” being used by the IAU is false and “sloppy”:

“We now have a list of well over 100 recent examples of planetary scientists using the word planet in a way that violates the IAU definition, but they are doing it because it’s functionally useful,” said Metzger. “It’s a sloppy definition. They didn’t say what they meant by clearing their orbit. If you take that literally, then there are no planets, because no planet clears its orbit.”

Makes you think, doesn’t it? This would hardly be the first official group to corrupt its own purpose for the sake of convenience, don’t you think?

Reason #3 – There Are More Accurate Ways To Define A Planet

One of the most compelling arguments from the new study of Metzger and co is that they acknowledge a very fundamental truth about planets and the universe: Things Change. So to say that a planet can be define via its orbit is erroneous because the orbits change in various ways and are affected by other objects:

“Dynamics are not constant, they are constantly changing. So, they are not the fundamental description of a body, they are just the occupation of a body at a current era… And that’s not just an arbitrary definition. It turns out this is an important milestone in the evolution of a planetary body, because apparently when it happens, it initiates active geology in the body.”

So what is their version of a ‘Planet’? What is their definition that they would go by? Well…

“A planet is a sub-stellar mass body that has never undergone nuclear fusion and that has sufficient self-gravitation to assume a spheroidal shape adequately described by a triaxial ellipsoid regardless of its orbital parameters.”

To be fair, this isn’t the best option because that would mean that many moons of our solar system would also be planets. But, not unlike science itself, that doesn’t mean it’s wrong, it just means that there “may” be more planets than you’d expect. Either way, this points out that the IAU’s definition of a planet was based on false information, and a rewrite of the definition is needed.

Reason #4 – Those Asteroids In The Belt Aren’t Exactly Like Pluto

One of the biggest proponents of the “Pluto is NOT a planet!” theory is that there are a lot of planet-like objects within the Kuiper Belt that are bigger than Pluto, have more mass than Pluto, and thus are more “planet-like” than Pluto. But is that really true?

Studies of Pluto have shown that there is a lot more history on its surface than people give it credit for. Sure, it’s not the most studied planet because of its distance, but that’s not a reason to discount it as a planet. Some have even noted that its geology is so “active” that it has an “interior  ocean, a multilayered atmosphere, organic compounds and evidence of ancient lakes and multiple moons”.

If you’re curious, the only planet that has more stuff than that in terms of potential and history…is Earth. I’m willing to bet the rocks in the Kuiper Belt don’t have that on their resumes.

Save Pluto!

I’m sure we seem a bit fanboyish in our vigorous defense of Pluto, but it’s something that means something to a lot of people. Whether it be scientists trying to defend the sanctity of scientific definition, or school kids who feel that the planet they’re been told about is still an actual planet. 

Now sure, having 8 planets in our solar system is a “nice round number”, but we’ve been told for SO LONG that we’ve had 9 that it feels wrong to go backwards. This wasn’t like in the early days of astronomy where we though the Earth was the center of the universe, or we were learning about what is in our own solar system. This is a bunch of people looking up and going, “nah, not a planet”. That’s not cool, or right, or even fun!

So yeah, we want Pluto back as a planet, and there are some very legitimate reasons to do so. So join us…and let’s make Pluto a planet again!

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