Astronomy Picture of the Day - Pluto in True Color

NASA ^ | 28 Jan, 2024 | Image Credit: NASA, JHU APL, SwRI; Processing: Alex Parker

[MtnClimber]

Explanation: What color is Pluto, really? It took some effort to figure out. Even given all of the images sent back to Earth when the robotic New Horizons spacecraft sped past Pluto in 2015, processing these multi-spectral frames to approximate what the human eye would see was challenging. The result featured here, released three years after the raw data was acquired by New Horizons, is the highest resolution true color image of Pluto ever taken. Visible in the image is the light-colored, heart-shaped, Tombaugh Regio, with the unexpectedly smooth Sputnik Planitia, made of frozen nitrogen, filling its western lobe. New Horizons found the dwarf planet to have a surprisingly complex surface composed of many regions having perceptibly different hues. In total, though, Pluto is mostly brown, with much of its muted color originating from small amounts of surface methane energized by ultraviolet light from the Sun.

[MtnClimber]

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For more detail go to the link and click on the image for a high definition image. You can then move the magnifying glass cursor then click to zoom in and click again to zoom out. When zoomed in you can scan by moving the side bars on the bottom and right side of the image.

[MtnClimber]

[MtnClimber]

Pinging the APOD list.

🪐 🌟 🌌 🍔

[Ken H]

[Yardstick]

Pretty bleak looking. Quick factoid: Pluto is about 2/3 the size of Earth’s moon.

[Telepathic Intruder]

I can rattle off a half dozen reasons why Pluto should not be a planet. And listen to dozens of reasons why it should. But still it’s worth half a billion dollars to just see what it looks like.

[Ronaldus Magnus III]

“”I am still a planet!””

Yeah baby!!

The ‘scientists’ who try to denigrate and diminish Pluto probably believe in Globull Crapola.

[Empire_of_Liberty]

I will bite!

Pluto orbits the Sun. I believe that all bodies in our solar system came from the Quasar it used to be. My belief is that nothing of Pluto’s size crosses the void between stars.

I do agree that Pluto’s orbital intersection of Neptune’s orbit means that one day, it will not be here.

But for now, it is a planet.

[EvilCapitalist]

I’m glad it’s Pluto in True Color, and not Uranus in True Color. That would be disgusting.

[telescope115]

That was an exciting time in astronomy!

[Telepathic Intruder]

"My belief is that nothing of Pluto’s size crosses the void between stars."

Interstellar space is believed to be literally teeming with planetary mass objects, ejected from their parent star by any number of known methods. But let me give you the short of it. Pluto is part of a larger collection of objects called Kuiper Belt Objects, which failed to form a planet and are instead a collection of debris similar to the asteroid belt. The asteroid Ceres was also considered a planet for one brief time, until it was discovered that it wasn't the only one out there. The IAU wisely (in my opinion) chose to define a planet as an object which has cleared its orbit of other similar objects. Pluto has not. In fact, Nepune has cleared Pluto from its orbit, forcing it into a 2:3 resonance orbit along with Pluto's "moons" (quotations because pluto is just the largest of them).

And then there is the matter of Pluto's discovery. It was originally calculated that some mass was perturbing the orbit of Neptune and Uranus, and so the search for a nineth planet began. Later it was found that those calculations were in error, and there was no nineth planet, but yet the search continued because years of research was already invested it in. When they finally discovered Pluto completely by accident, it was rushed to planet status before anything was really known about it. It never belonged there in the first place, in my opinion.

Sorry for the rant.

[Fester Chugabrew]

I often enjoy these Astronomy Picture of the Day. It almost has me working toward a Gastronomy Picture of the Day, too.

[Telepathic Intruder]

It was a long time coming.

[Empire_of_Liberty]

No. Don’t apologize!

The definition of a “planet” makes sense. As I said, I can see how Pluto will not always be here.

But, your mention of interstellar space causes me to voice my own conviction, again:

I do not believe that matter in any appreciable or planetary volume travels between the stars. The heavy elements that comprise all of the planets, asteroids and even objects in this “Kuiper Belt” are ejecta from a Quasar that used to be where our Solar System is.

At least, that is the best of my understanding.

[alexander_busek]

I believe that all bodies in our solar system came from the Quasar it used to be.

Quasars had nothing to do with the formation of our Our Solar System. You apparently have no understanding of the meaning of the word Quasar.

My belief is that nothing of Pluto’s size crosses the void between stars.

The trans-Neptunian object Eris outmasses Pluto, but has a slightly smaller diameter.

Regards,

[eclecticEel]

The number of known planets is already in the thousands and soon enough will be in the millions. For now, most of the known bodies are large, but as time goes on smaller and smaller bodies will be detected. There’s no possible definition of ‘planet’ that will be able to place all of these objects into neat categories. Create a rule if you want, but realize there will always be exceptions, like Pluto, our ninth planet. Because we say so.

[Telepathic Intruder]

Not a quasar, but a supernova or neutron star binary collision. The latter is a more popular theory based on, believe it or not, the amount of gold present in the solar system. Either one is known to trigger star cluster formation.

And to be fair, the term "planet" has always been of variable definition. It originally meant "wandering star" in ancient Greek, and didn't even include the earth. Whether or not the IAU's new definition is set in stone depends on popular opinion and future discoveries.

[Telepathic Intruder]

Indeed. It’s hard to categorize things into groups when you know very little about that group.

[Empire_of_Liberty]

Thanks. I can see that Quasars are larger than I was recollecting.

I don’t see anything that suggests that Eris has traveled from another star, following your link.

[Empire_of_Liberty]

Another poster has already pointed out that a Quasar is a much larger body.

Is there a term for a Sun-like body large enough to be fusing Uranium, but not as large as a Quasar? I expect this type of body may end in a Supernova.