If you turn on the 'Stars' in that, you'll see that its currently in the interesting direction of the sky - 'twards the center of the Milky Way where we've got other telescopes looking. I wonder if we would have detected it if it was 180° further in its orbit.
ecshafer 2 hours ago [-]
There was a lot of negative press and commentary about "demoting" Pluto from being a planet at the time. But its obviously true that it was the right move, and creating this "dwarf planet" class of objects was correct. It was hard to justify Pluto being a planet when Ceres exists, but Eris, Haumea, Makemake and all of these other possible Dwarf planets are the nail in the coffin.
skissane 2 hours ago [-]
> But its obviously true that it was the right move, and creating this "dwarf planet" class of objects was correct. It was hard to justify Pluto being a planet when Ceres exists, but Eris, Haumea, Makemake and all of these other possible Dwarf planets are the nail in the coffin.
I don't agree that "its obviously true that it was the right move". Instead of demoting Pluto, they could have promoted Ceres, and let Eris, Haumea, Makemake, etc, be planets too. Under that proposal, they could even have the category of "dwarf planets" encompassing them, it is just that "dwarf planet" would be a subcategory of planets rather than a disjoint category from them.
delta_p_delta_x 1 hours ago [-]
Classifications are useful. Even the 'proper' planets we split into terrestrials, Jovian giants, and ice giants. Each planet is individually interesting in itself. One might even argue all of the bodies in the Solar System exist on a continuum of mass from the tiniest mote of space dust, to rocks and asteroids, to moons and dwarf planets to terrestrial planets, ice giants, giants, and then the Sun, and then hypergiant stars, neutron stars, black holes, and then supermassive black holes, so let's call all of them 'celestial objects'—which we kind of do. But such a catch-all is pointless. Each object behaves very differently, with wildly different physical laws governing its interior and its neighbourhood.
Classifications impose structure on a collection of celestial objects, and we can derive relationships, commonalities, understand their development, the physics governing these objects, and build useful physical and mathematical models to widen our understanding of the universe.
Most reasonable scientists understand that some of these objects will blur the edges—like many moons being more massive and larger than Mercury. Or like the largest super-Earth exoplanets being nearly as massive as Neptune, or the largest gas giant exoplanets being 30-80 times as massive as Jupiter and hence having a surface temperature of ~2000 K. But that is part of science, and possibly even where the most interesting work is.
jl6 17 minutes ago [-]
Yes, regardless of the specific labels, there are clearly interesting and meaningful differences between these things, and it’s worth having vocabulary capable of distinguishing them. The whole universe is a continuum of stuff but it helps to have more than just the word “stuff”.
cookingmyserver 21 minutes ago [-]
Classifications are useful! It is poor form to take a widely used and historic term and add on a whole different (dynamic!!) category of attribute as a filter on the definition. There is quite a bit of absurdity in the 2006 IAU's definition of a planet. If a massive object came into the solar system and perturbed orbits, caused chaos and collisions, then any "planet" with debris within its neighborhood would cease to be a planet. What do we gain from adding a whole different category of attribute (relationship to its neighborhood) as a criterion? Does it realistically outweigh decades or centuries of peoples intuition of the existing definition? Its not just a matter of science, but language and communication. If you want greater specificity, come up with a new term or use compounded terms.
It very much seems like the definition was just shoe-horned to stem any more planets needing to be added. It would be interesting to know if astronomers walk the walk when it comes the definition. If I research when planets were formed would I get the date when their neighborhoods were cleared? Do discussions around large events that send debris into the neighborhood of planets correctly reflect that they cease to be planets until it is cleared?
Alan Stern said it best
>"We're going to call it a cow, except when it's in a herd." A river is a river, independent of whether there are other rivers nearby. In science, we call things what they are based on their attributes, not what they're next to.
>And the IAU definition is even worse, because it produces different categorizations for identical objects, depending on where they are. Get this — Earth at the same distance from the sun [as Pluto] would not be a planet by the IAU’s measure, because Earth can’t clear that zone either. I would say any definition that produces a result where Earth is not a planet under any circumstance is immediately indicted as ridiculous, because one thing we all agree is a planet is planet Earth!
>That's crazy. No wonder teachers and students are frustrated, confused, unhappy. It reflects poorly on astronomy, to have something so illogical.
Yeah. The gas giants are clearly way different from rocky planets and we still keep them all under one taxonomical grouping. Pluto and other bodies should have been an extension of that: make them dwarf planets or whatever other classification you want. But they're still planets. Theres no "demotion" just a further categorization.
joquarky 55 minutes ago [-]
Yeah, I don't like when a modifier is mandatory. If they chose to label them "dwarf planets" then it should be expected that people will leave off the modifier "dwarf" when being concise.
If they really didn't want people to continue to refer to them as planets, then they should have chosen a completely different noun.
Teever 2 hours ago [-]
To me this subject is just a combo of bikeshedding[0] lumper and splitter[1] stuff by people who aren't domain subject experts.
I find people do this a lot with space stuff because they're interested in it but don't really know much about it.
It's ultimately irrelevant to the subject at hand and detracts from the conversation.
And a spattering of domain subject experts being offended that they don't have veto power over colloquial terminology
klez 40 minutes ago [-]
You can just keep calling it a planet in everyday conversation if that's your jam. There's no astronomy police that will come to get you if you do.
Just expect to be corrected and "well, achually"-ed by people who follow the current naming system, especially in science circles.
mturmon 22 minutes ago [-]
Right. Somewhat similar to other dual-use words like “work”, “energy”, “power”, “momentum”.
With such “well, ackshually”s as “you didn’t really do any work at all when you were pushing on that tree trunk” and “you specified watts, but you really wanted to use lumens”.
hdgvhicv 2 hours ago [-]
Ok so we have 50 planets?
whiskers 2 hours ago [-]
I mean, why not?
jandrese 1 hours ago [-]
It would make the mnemonic for memorizing the order of the planets very long and difficult for the children to remember.
My Very Elegant Mother Just Served Us Nachos
55 minutes ago [-]
sandworm101 2 hours ago [-]
Yes. I wouldn't call a dwarf person any less of a person, nor would i refer to a dwarf planet as being any less a planet. Between the terrestrial planets, the gas giants, the ice giants, and arguably a couple of rounder moons, we have far more than 50 planets in our solar system.
By some extreme definitions, Earth might not be a planet. Some say the moon is too big to qualify the earth "cleared out its orbit" criteria, making Earth-moon some sort of double planet... like Pluto-Charon.
GolfPopper 2 hours ago [-]
Setting aside the whole "demote Pluto" and "dwarf planet" aspects, I find it amusing that we use the same term for small rocky Mercury (2,440 km radius, 5% of Earth's mass) and immense gaseous Jupiter (69,000 km radius, over 300 times Earth's mass). Only we don't, of course. Jupiter is a gas giant, while Mercury is a rocky planet, or iron planet; there's a lot of 'planet' terminology.
Ultimately these sorts of quibbles are fundamentally semantic in nature thus (in general) entirely pointless. It's only the subjects themselves - the myriad celestial bodies - that are interesting.
interestica 22 minutes ago [-]
It's semantics as well as a collision with our inability to work with gradients. We can look at two colours and can name the discrete ones - but when does red stop being red? When does a species emerge?
manquer 2 hours ago [-]
Why is Jupiter in the same category as planets then?
Jupiter does not orbit the sun (the first requirement per IAU definition of planet), the barycenter for the system is not inside the surface of Sol at 1.07 solar radius.
It is not planet then yes ? There is no push to promote it to a sub-brown dwarf or a new category .
Classifications are always arbitrary and only fits some bias one way or other.
delta_p_delta_x 1 hours ago [-]
A planet is an object that:
a) orbits a star, and is not a star nor a brown dwarf itself;
i) a star is an object that is massive enough and hot enough to conduct protium fusion in its core
ii) a brown dwarf is an object that is massive enough to conduct deuterium fusion, but insufficiently massive (and hence insufficiently hot) for protium fusion
b) has attained hydrostatic equilibrium, that is, it is spheroidal;
c) it has cleared its local neighbourhood of 'rival planets' since its birth;
Ergo, Jupiter is a planet. It is a certain type of planet—a gas giant—but a planet nonetheless.
There is some controversy about when giant planets stop being giant planets and start being brown dwarfs—typically around 30 Jupiter masses—but this is an active area of research, to understand the fusion ignition in these objects. As I mentioned in another comment, classifications are useful. Of course they are arbitrary and they are biased—they were decided by humans. But the entire point of science is to push the edges of our understanding and reduce these biases and make our models more general and less arbitrary.
zmgsabst 1 hours ago [-]
Their claim is that it fails (a) because the Sun and Jupiter orbit a common barycenter, and hence Jupiter does not orbit the Sun (or any star).
delta_p_delta_x 56 minutes ago [-]
Everything orbits a barycentre. The position of that barycentre within or without the primary is not really relevant within several orders of approximation—and when it does become relevant, then that system becomes interesting in itself. Chances are the planet in question is so massive relative to its primary that we need to ask a more fundamental question: are we even looking at a star-planet relationship, or is it closer to a binary star system? Then we can investigate how that system formed and developed, and generalise and improve our model of stellar/planetary system development.
Eridanus2 56 minutes ago [-]
I agree with this picture as the barycenter argument seals it for me. The only leap left is for me to believe Ol'Jove as a failed star (it still emits heat in excess of what it derives from Sol) and we find ourselves cozily herded about by a binary star system.
paipa 2 hours ago [-]
I initially assumed from your comment that all of those objects are larger than Pluto, but none of them are, so what exactly is "obvious" about the decision? They haven't resolved any inconsistency by demoting it.
GolfPopper 2 hours ago [-]
Eris has more mass. And our Moon, the Galilean moons of Jupiter, Titan and Triton are all both larger and more massive.
bradyd 40 minutes ago [-]
Ganymede and Titan are both larger than Mercury.
antonvs 2 hours ago [-]
Ceres by itself doesn't really challenge Pluto's old classification. Pluto has 14 times the mass of Ceres, and five moons. Ceres is the only "dwarf planet" classified so far that has zero moons. There are still good arguments for a definition that doesn't consider Ceres a dwarf planet.
This helps illustrate how arbitrary these classifications are. They depend entirely on what properties are included in the definition. The updated IAU definition is essentially reverse engineered to fit how they wanted to classify the planets.
kergonath 2 hours ago [-]
So, a factor of 14.4 is enough to put the line between Ceres and Pluto, but a factor of 23.0 is not enough to put it between Pluto and Mercury?
Yes, those classifications are arbitrary, but then any classification is. If you want to consider Pluto as a planet, you have to include quite a lot of other bodies, which are all qualitatively and quantitatively different from the 8 (which themselves are in 2 qualitatively and quantitatively different groups. Or 3, depending on who you ask).
In the grand scheme of things, it does not matter and astronomers won’t care about the general public’s feelings. It is utterly pointless to get worked up about these things.
cwillu 1 hours ago [-]
The problem is not experts having precise terminology in technical settings; the problem is the army of “experts” who will descend upon you if you use the incorrect arbitrary term in colloquial settings. The same sort that will descend on you if you dare refer to a planet orbiting a different star as a planet, not an exo-planet.
fc417fc802 1 hours ago [-]
> The updated IAU definition is essentially reverse engineered to fit how they wanted to classify the planets.
I wholeheartedly agree with this take. I have something of a personal hatred of poorly executed retconning thus I present the following proposal.
For the sake of simplicity we should use even powers of 10 with earth as the primary reference point. Note that the earth is 10^24, mars is 10^23, and the earth's moon is 10^22 (pluto is also 10^22 and less massive than the earth's moon). It seems "obvious" then that 23-25 are planets, 22 or less are relegated to dwarfs, and 26 and over are giants (jupiter is a 27 and the sun a 30 for reference).
By that logic, if we want to consider pluto a planet then the earth's moon also has to qualify. I don't really care one way or the other but that just doesn't seem sensible to me.
libria 2 hours ago [-]
I'm just salty about only getting served "Noodles" instead of "Nine Pizzas" from my very educated mother.
mcphage 45 minutes ago [-]
You merely need to define the term "NinePizza", which is a collection of nine pizzas—and then have your very educated mother serve that. This doesn't present any problems philosophically, since we already have terms like "Solar System" for collections of disconnected objects.
Gibbon1 33 minutes ago [-]
Maybe we haven't gone far enough. We should refer to Uranus and Neptune as Trans Saturn Objects.
GolfPopper 20 minutes ago [-]
Does Saturn have enough density to count, though? I mean, from a certain point of view, it's more of a spheroid of hydrogen with a bit of helium. Maybe we need a new term for it, like "Planetary nebula"? ;)
christophilus 3 hours ago [-]
> They even found it in photographic plates from 1937
Pretty rad.
reenorap 2 hours ago [-]
Is this Planet X that they have been talking about for a while now?
FranOntanaya 2 hours ago [-]
No, all dwarf planets are too small to affect orbits the way that hypothetical planet is supposed to do.
It's too small to affect other orbits as much as the hypothetical planet X.
nntwozz 20 minutes ago [-]
They should call it Twitter.
(Character limit 280)
dvh 2 hours ago [-]
> The new dwarf planet candidate, called 2026 ED138, orbits on a plane tiled nearly 25 degrees
I've noticed similar glaring typos in 2 recent articles. In both cases very early in the article. Is it possible that they are adding typos intentionally to mask the AI authoring?
coffeefirst 2 hours ago [-]
No. It's understaffing. Magazines used to have robust copy desks. Very few still do.
dzonga 2 hours ago [-]
so there's potentially undiscovered planets in our own neighborhood ?
GolfPopper 14 minutes ago [-]
Yep. Who knows, maybe there's a sub-dwarf of 10 Jupiter masses faintly emitting in the infrared out there.
kraig911 2 hours ago [-]
Nibiru!
vld_chk 51 minutes ago [-]
So, this is another new candidate, different from the one from a week ago?
smallerize 42 minutes ago [-]
No it's still 2026 ED138.
Rendered at 22:10:38 GMT+0000 (Coordinated Universal Time) with Vercel.
(This uses wasm, meant for a desktop, and will download the asteroid catalog of about 65mb, you have been warned)
https://dahlend.github.io/ketev/#t=2009-07-01.717&sel=2026%2...
This is a big boy.
I don't agree that "its obviously true that it was the right move". Instead of demoting Pluto, they could have promoted Ceres, and let Eris, Haumea, Makemake, etc, be planets too. Under that proposal, they could even have the category of "dwarf planets" encompassing them, it is just that "dwarf planet" would be a subcategory of planets rather than a disjoint category from them.
Classifications impose structure on a collection of celestial objects, and we can derive relationships, commonalities, understand their development, the physics governing these objects, and build useful physical and mathematical models to widen our understanding of the universe.
Most reasonable scientists understand that some of these objects will blur the edges—like many moons being more massive and larger than Mercury. Or like the largest super-Earth exoplanets being nearly as massive as Neptune, or the largest gas giant exoplanets being 30-80 times as massive as Jupiter and hence having a surface temperature of ~2000 K. But that is part of science, and possibly even where the most interesting work is.
It very much seems like the definition was just shoe-horned to stem any more planets needing to be added. It would be interesting to know if astronomers walk the walk when it comes the definition. If I research when planets were formed would I get the date when their neighborhoods were cleared? Do discussions around large events that send debris into the neighborhood of planets correctly reflect that they cease to be planets until it is cleared?
Alan Stern said it best
>"We're going to call it a cow, except when it's in a herd." A river is a river, independent of whether there are other rivers nearby. In science, we call things what they are based on their attributes, not what they're next to.
>And the IAU definition is even worse, because it produces different categorizations for identical objects, depending on where they are. Get this — Earth at the same distance from the sun [as Pluto] would not be a planet by the IAU’s measure, because Earth can’t clear that zone either. I would say any definition that produces a result where Earth is not a planet under any circumstance is immediately indicted as ridiculous, because one thing we all agree is a planet is planet Earth!
>That's crazy. No wonder teachers and students are frustrated, confused, unhappy. It reflects poorly on astronomy, to have something so illogical.
https://www.space.com/12710-pluto-defender-alan-stern-dwarf-...
If they really didn't want people to continue to refer to them as planets, then they should have chosen a completely different noun.
I find people do this a lot with space stuff because they're interested in it but don't really know much about it.
It's ultimately irrelevant to the subject at hand and detracts from the conversation.
https://en.wikipedia.org/wiki/Law_of_triviality
https://en.wikipedia.org/wiki/Lumpers_and_splitters
Just expect to be corrected and "well, achually"-ed by people who follow the current naming system, especially in science circles.
With such “well, ackshually”s as “you didn’t really do any work at all when you were pushing on that tree trunk” and “you specified watts, but you really wanted to use lumens”.
My Very Elegant Mother Just Served Us Nachos
By some extreme definitions, Earth might not be a planet. Some say the moon is too big to qualify the earth "cleared out its orbit" criteria, making Earth-moon some sort of double planet... like Pluto-Charon.
https://en.wikipedia.org/wiki/List_of_planet_types
Jupiter does not orbit the sun (the first requirement per IAU definition of planet), the barycenter for the system is not inside the surface of Sol at 1.07 solar radius.
It is not planet then yes ? There is no push to promote it to a sub-brown dwarf or a new category .
Classifications are always arbitrary and only fits some bias one way or other.
There is some controversy about when giant planets stop being giant planets and start being brown dwarfs—typically around 30 Jupiter masses—but this is an active area of research, to understand the fusion ignition in these objects. As I mentioned in another comment, classifications are useful. Of course they are arbitrary and they are biased—they were decided by humans. But the entire point of science is to push the edges of our understanding and reduce these biases and make our models more general and less arbitrary.
This helps illustrate how arbitrary these classifications are. They depend entirely on what properties are included in the definition. The updated IAU definition is essentially reverse engineered to fit how they wanted to classify the planets.
Yes, those classifications are arbitrary, but then any classification is. If you want to consider Pluto as a planet, you have to include quite a lot of other bodies, which are all qualitatively and quantitatively different from the 8 (which themselves are in 2 qualitatively and quantitatively different groups. Or 3, depending on who you ask).
In the grand scheme of things, it does not matter and astronomers won’t care about the general public’s feelings. It is utterly pointless to get worked up about these things.
I wholeheartedly agree with this take. I have something of a personal hatred of poorly executed retconning thus I present the following proposal.
For the sake of simplicity we should use even powers of 10 with earth as the primary reference point. Note that the earth is 10^24, mars is 10^23, and the earth's moon is 10^22 (pluto is also 10^22 and less massive than the earth's moon). It seems "obvious" then that 23-25 are planets, 22 or less are relegated to dwarfs, and 26 and over are giants (jupiter is a 27 and the sun a 30 for reference).
By that logic, if we want to consider pluto a planet then the earth's moon also has to qualify. I don't really care one way or the other but that just doesn't seem sensible to me.
Pretty rad.
https://en.wikipedia.org/wiki/Planets_beyond_Neptune
(Character limit 280)
I've noticed similar glaring typos in 2 recent articles. In both cases very early in the article. Is it possible that they are adding typos intentionally to mask the AI authoring?