Planetary Classification Quotes

If you put Earth out beyond Neptune, you wouldn't be able to call it a planet because it couldn't clear its zone.

The planets. Now footnote, I'm including Pluto in the planets, because I think it's terrible what they did to Pluto. And it's still a planet to me. I grew up with Pluto as a planet, it will always be a planet.

If you go to planetary science meetings and hear technical talks on Pluto, you will hear experts calling it a planet every day.

I think when people see Pluto revealed by New Horizons, its satellite system, its complex surface, its atmosphere, I think they'll have a hard time saying 'That's not a planet' because it obviously will be, and I think most people are already coming to that opinion anyway, but I think that's really going to drive it home viscerally.

I knew Pluto was popular among elementary schoolkids, but I had no idea they would mobilize into a 'Save Pluto' campaign. I now have a drawer full of hate letters from hundreds of elementary schoolchildren (with supportive cover letters from their science teachers) pleading with me to reverse my stance on Pluto. The file includes a photograph of the entire third grade of a school posing on their front steps and holding up a banner proclaiming, 'Dr. Tyson - Pluto is a Planet!'

Pluto is not a planet, but I am.

Of course Pluto is a planet: It's massive enough to have its shape controlled by gravity rather than material strength, which is the hallmark of planethood.

It used to be said that Pluto is a misfit. But now we know Earth is the misfit. This is the most populous class of planet in our solar system and we have never sent a mission to this class.

It's interesting - Pluto's almost a brand unto itself. It's the farthest. It's the most diminutive of the classical planets. It's been maligned by astronomers. It's always the one with all the question marks in the back of the textbook in the table. I think children identify with it because it's smaller, kind of cute.

Back before the Kuiper Belt was discovered, Pluto did look like a misfit that didn't belong with either the terrestrials or the giant planets.

I call Pluto the harbinger.

To say that what a planet is doesn't matter would be to imply that a planetary scientist couldn't explain to someone what the field is about.

Discovering that our solar system has many more planets than we ever expected, and that most of them are ice dwarfs rather than like Earth and the other rocky terrestrials, is just another step in the revolution in viewpoint that removed the Earth from the center of the physical universe and makes Earth all the more special.

Just because Pluto orbits with many other dwarf planets doesn't change what it is, just as whether an object is a mountain or not doesn't depend on whether it's in a group or in isolation.

People know a planet when they see one, and I think that's a pretty darn good test, in fact, for planethood.

As a planetary scientist, I don't know what else to call Pluto: It's big and round and thousands of miles wide.

I'm the one who originally coined the term 'dwarf planet,' back in the nineteen-nineties.

Why can't Pluto be a planet? Some people like Pluto. And if it doesn't exist then they don't have a favorite planet. Right? Please write back but not in cursive because I can't read cursive.

I refuse to accept Pluto's resignation as a planet.

Pluto and its brethren are the most populous class of planets in our solar system.

In the mind of the public, the word 'planet' carries a significance lacking in other words used to describe planetary bodies... many members of the public assume that alleged 'non-planets' cease to be interesting enough to warrant scientific exploration.

All Plutophiles are based in America. If you go to other countries, they have much less of an attachment to either the existence or preservation of Pluto as a planet.

We're just learning that a lot of planets are small planets, and we didn't know that before, fact is, in planetary science, objects such as Pluto and the other dwarf planets in the Kuiper Belt are considered planets and called planets in everyday discourse in scientific meetings.