New Horizons visited Pluto 10 years ago. We're still learning from it

[usonian]

https://www.sciencenews.org/article/new-horizons-pluto-flyby-anniversary

Planetary scientist Kelsi Singer was an undergraduate in 2006 when a spunky spacecraft launched with an ambitious goal: to fly by Pluto. It would take nearly a decade for the New Horizons probe to zoom past its target in the far reaches of the solar system.

“Oh, that’s so far off,” Singer thought at the time. “Nine and a half years to get to Pluto? That’s like forever.”

Now, Singer, who is deputy principal investigator for the New Horizons mission, and other scientists are celebrating the 10th anniversary of the spacecraft’s historic encounter with the beloved dwarf planet. New Horizons got within 12,500 kilometers of Pluto’s surface. Images and other data gathered during the flyby have transformed researchers’ understanding of the icy world.

“We all thought Pluto would be a little bit less interesting than we found it; we thought it would be more cold and dead,” says Singer, of the Southwest Research Institute in Boulder, Colo. “Since the flyby, we have basically rewritten the textbooks.”

A sheet of nitrogen.

[cos dem]

1. Wow, hard to believe it's been 10 years since we visited our 9th planet.

Yeah, I went there!

[NNadir]

2. It will always remain a planet in my heart.

[Jeebo]

3. They stopped calling it a planet when they realized how small it is.

After all, it's smaller than our moon. C'mon, it's not a planet!

— Ron

[NNadir]

4. Well a midgit is still a man, as well I know when my wife back when she was my...

...girlfriend put her arms around me and said, "You're such a little guy."

What makes a "little guy" like me a man is how I behave, not how big I am.

Pluto, together with Charon, orbits the sun, not Neptune. That's how they behave, which is very different than our moon.

[Jeebo]

5. Part of the definition of a planet is its size.

I'm not sure what that lower size limit is, but I am sure Pluto's size is well below that limit. It's officially a dwarf planet. And it was when they realized how small it is that they re-classified it as a dwarf planett.

— Ron

[NNadir]

6. Yeah, I know. They certainly aren't interested in my opinion nor should they be but...

...the criteria I would choose would not so much be based on size but would involve orbital parameters and spherical symmetry.

I know it orbits out of plane so there's that, and I'm certainly not a planetary astronomer, and the whole world can disagree with me, but as a stubborn old bastard, pluto is a planet in my heart if no one else's.

One of my favorite elements in the periodic table, plutonium was named on the consideration of of Pluto's former official status as a planet in the sequence uranium, neptunium, plutonium I would hate for my much beloved element to be called Gilese581gium.

Thus far, at least up until the recent adventures with comets and asteroids, out of Earth's orbital probes have been sent to planets.

[Jeebo]

7. I saw a t-shirt once that said ...

I REMEMBER WHEN
THERE WERE NINE PLANETS

If I knew where to get one, I would buy it and send it to you.

— Ron