145 moons? This is Pluto levels of disrupting my comprehension of the nearest spec of a spec of a spec of the cosmos. What’s next? Are you going to replace the cosmological constant with a complex series of equations? Are you going to change your minds on the entropic fate of the universe?
You identify that Pluto hasn’t cleared its orbit of asteroids and so you demote it. You know what engineers would do? Engineers would go help Pluto tidy up.
145 moons? Inelegant. It’s time for some refactoring.
> You identify that Pluto hasn’t cleared its orbit of asteroids and so you demote it.
That wasn't really why it was demoted. Eris was discovered, and it was more massive than Pluto, so a decision was to be made about whether we were going to say there were more than nine planets (and admit we don't know exactly how many planets there are in our solar system), or kick out Pluto and just say there are 8. The IAU made a decision about this, not for scientific reasons but for naming conventions (they have a different naming convention for planets and non-planets).
Keep in mind that though some planetary scientists are in the IAU, most members of the IAU aren't planetary scientists, and my understanding is that most planetary scientists aren't members of the IAU (someone correct me if I'm wrong here). But the IAU is responsible for naming things in the night sky.
The initial definition that was suggested didn't include the criteria for clearing the neighborhood, add a bunch of new planets to our solar system, and say we didn't know how many planets there were in our solar system. Members objected, and went with the simpler solution of just kicking Pluto out and saying there are now 8 planets (the definition with the vague "clearing the neighborhood" part of the definition).
I have to say I prefer the original suggestion for the definition of planet; it does a much better job of conveying to people how much cool stuff is in our solar system and how much we still don't know. As far as I can tell planetary scientists aren't fond of the IAU definition and tend to ignore it (though Alan Stern has lead apublic campaign to get rid of IAU's definition).
> The IAU made a decision about this, not for scientific reasons but for naming conventions (they have a different naming convention for planets and non-planets).
“The name is intended to reflect the characteristics of the body itself, and be an appropriate moniker derived from mythology. Objects, including dwarf planets, far beyond the orbit of Neptune are expected to be given the name of a deity or figure related to creation”
Pluto is a Greek god related to the underworld, not to creation, so it doesn’t fit that pattern, does it?
Also, it’s not “non-planets”, it’s “dwarf planets”. Pluto still is considered a planet in the terminology of the IAU, but not a ‘planet planet’ (my term, not an IAU one)
No, according to the IAU Pluto and other dwarf planets are not a planet and there's only 8 planets in the solar system, and dwarf planets aren't considered planets. For example, from their site[1]:
> The 2006 IAU Resolution means that the Solar System officially consists of eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. In the same resolution, a new distinct class of objects, called dwarf planets, was also defined.
Dwarf planets not being considered planets is just one of the reasons why the current definition is viewed by some as less than ideal.
I love the internal conflict contained in that statement. In any other context it would be ridiculous. Dwarf dogs aren't considered dogs. Dwarf humans aren't considered humans.
The entire controversy isn't about definitions or scientific accuracy. It is about reclaiming history. It is about a small group of today's scientists wanting to assert their power through language. It is about asserting dominance by redefining language to create a break between those who are educated in the modern lexicon and the ignorant who came before. It is about declaring all previous works about the solar system wrong, or at least old hat, not through argument but by decree. It is the exact opposite of scientific pursuit.
GPT: Nibiru, or Planet X, is a hypothesized planet in our solar system that conspiracy theorists claim will collide with or pass close to Earth, causing catastrophic destruction. They assert that this event, often referred to as the "Nibiru cataclysm," is being concealed by governments and scientists worldwide.
Hm, maybe they should do something similar as with the planets and include hydrostatic equilibrium into the definition of a "moon". Which would mean that Mars has 0 moons and 2 "minor moons".
Why do you think they are sending all of the probes? You need a baseline understanding of the materials available before you can really come up with a plan to merge, delete, etc.
I know this sounds crazy but it kind of makes sense to me. It's a large boulder in the context of things you might find obstructing the road, but it's a small boulder in the context of all boulders. Still pretty hilarious to read.
Astronomical Units and Lightyears do just fine. Maybe the rest of the world will try them someday though, I guess terameters and petameters are useful if you need to know how many microns it is to Jupiter.
Rhode Islands are only used when you want to show how small something is. It's a like the centimeter. It looks like a lot, but really, it's not when compared to a useful measurement ;-)
> Saturn's system currently hosts three of these groupings — the Inuit group, the Gallic group and the densely populated Norse group, all of which take their names from different mythologies.
> All of the newfound moons of Saturn fall into one of these three currently existing groupings. Three of the new moons belong to the Inuit group, but the majority fit in the Norse group.
TIL Saturn's moons are named after various human groups.
Named after characters in the mythologies of the groups, e.g. Fenrir from Norse mythology. Initially they were all named after Titans (because Saturn is a Titan), but they ran out of Titans. As far as I can tell, the Norse names are all names of Jötunn which are to some extent a parallel to Titans in Norse mythology.
I like that the moons of Uranus are names after Shakespeare characters.
I think when I was a kid I could probably have named the canonical list of moons known at the time. I'm pretty sure that would be a very impressive feat today.
I would have struggled to match you, but easily doable as I did know Jupiter had 12 moons and Saturn 9 (this was in the 1970s, but the books I was reading were probably old). Having said that, Jupiter had 4 and Saturn 1 'real' mini-planet sized moons then as now. I definitely knew the names of all of those :-)
I'm not sure what I said was literally true. The Galilean moons and Saturn's Triton certainly. But a bunch of others in the 60s I could probably have named (I think Jupiter was up to about a dozen by then and Saturn maybe nine) given I was pretty into space/astronomy. Forget about Uranus and Neptune at that point and pretty sure Charon hadn't been discovered since Pluto was a hazy spot. Knew Mars obviously.
If it's not on the solarquest board game, it's not a real moon or planet. (Although I just found an image of the board reprinted with Makemake, which definitely wasn't there when I played.)
I always thought it would be cool if multiple habitable planets could exist as moons of some large gas giant and civilizations on these planets could fly around the short distances of their planetary system visiting each other. Alas, it is not possible. Habitable planets can’t seem to really form as satellites for a larger world as explained to me once.
On a scale of how far their gravity well extends to suck things up, Saturn and Jupiter are both like the vacuums of the solar system, collecting long period orbit rocks and rubble piles.
The minimum size isn't defined, but that's okay the maximum size isn't defined either! The orbit has to be identified. So every particle within Saturn's rings doesn't qualify, at least not yet.
But that's because the star / planet boundary is fusion in the core, and thus Jupiter isn't a star. If Jupiter had fusion in its core, we could consider it a binary star system.
True, but if Jupiter was a dwarf star, we would consider it a binary star system even if its barycenter with the Sun remained within the Sun's surface. (Not that that would be possible in practice since even the least massive stars are more than 50x Jupiter's mass). That is, binary planet means external barycenter AND both objects must be planetary in nature. If the objects are small enough the term binary asteroid could come into play.
Several years ago I bought myself a post-WWII era copy of Hanmerton’s “Practical Knowledge For All” - the English encyclopaediast had edited together 50 educational courses in a set of 6 books. I love immersing myself in both the content and the historical context of the lessons.
Back then, Jupiter had 11 moons and Saturn had 9 “plus the doubtful Themis” which was discovered by an American astronomer in 1905 but never seen again…
Saturn of course has no "surface" to speak of, and its atmosphere is opaque, but just imagine what it must be like on a planet with 145 moons and moonlets whirling overhead. Plus those amazing rings.
Not quite the same (and not updated) but here's a simulation of the view from Mimas and Iapetus:
In English the word "planet" and the planets themselves are gender neutral. "Venus" may have originally been the name of a female god, but the planet itself is it/it:
> Venus is the second planet from the Sun. It is a rocky planet with a mass and size narrowly second in the Solar System to Earth
Possibly. Venus has no moons, so it's also possible Earth would have none if not for Theia. Mars does have moons, but they might have been captured from the asteroid belt.
Can someone explain to me how we're only discovering these moons in 2023? Do we really not have sensitive enough instruments to see rocks over a mile in diameter in our own solar system?
A lot of these search problems are easier to wrap ones head around with the keys analogy: finding a moon around Saturn, or finding a lost ship on the ocean* is like losing your car keys in a field then trying to find them with a pair of binoculars. If you do actually know where they are then you can easily see them with the binoculars but if you need to perform a search it is laborious because of the relative scales.
It’s equivalent to seeing an object one micron in size at a distance of a mile. Or like seeing something one nanometer in size at a distance of 1 meter (for example that’s about the size of a water molecule). And it’s constantly moving.
You need to stop.
145 moons? This is Pluto levels of disrupting my comprehension of the nearest spec of a spec of a spec of the cosmos. What’s next? Are you going to replace the cosmological constant with a complex series of equations? Are you going to change your minds on the entropic fate of the universe?
You identify that Pluto hasn’t cleared its orbit of asteroids and so you demote it. You know what engineers would do? Engineers would go help Pluto tidy up.
145 moons? Inelegant. It’s time for some refactoring.
Spatially yours,
Me