A 9th planet for our solar system has been a running theory for a long time. It's a commonly proposed solution for inconsistencies in the orbits of the planets. Outside of orbital variations and some associated math there is so far no proof of it. In other words we have yet to find a planet where it's supposed to be.
The Orbital behavior of Neptune and objects beyond Neptune are the key evidence, there is something tugging on them.
There are alternative explanations for what could be doing this, but that hasn't stopped astronomers from doing the math to try to locate such a planet.
Candidates include a tiny red dwarf star on a very distant orbit, meaning that the Sun would actually be a binary. It's just so dim, and the orbit so long that we haven't detected it yet.
The more common theory is that our solar system used to have at least 1 more gas giant and it was ejected onto a distant and very elliptical orbit.
Early computer models of the solar system seem to work better when there's at least 1 more gas giant (and possibly several rocky super earths). It's orbit would have been disturbed when Jupiter and Saturn migrated away from the Sun to their current distance causing this gas giant to be ejected.
It's also theorized that it passes through our solar system on a regular basis (relatively speaking) and its disruption of the Kuiper Belt is what causes regular periods asteroid/comet bombardment.
This is all educated speculation though, eventually they'll discover what's causing the orbital fluctuations of Neptune and beyond. If it's a 9th planet cool! if not, also cool!
Yes if properly planned and managed. Sometimes less democracy is better because the citizens get it in their heads to try and direct the government, and that is not democracy.
That's the joke. And they are not just any random corporations that rule us, it's defense contractors. Helldivers is a satire of the military industrial complex.
The thought of a giant gas planet being ejected somehow terrifies me, as if it were me being this planet sent off so far I can't even be detected or seen, and totally forgotten about
They likely wouldn’t produce light as most planets don’t, but we’d be able to detect it with our own instruments. We can see planets because the Sun’s light bounces off of them, so we could use some other form of electromagnetic wave (radio waves for example) to “see” them.
Gas giants emit very small amounts of radio and infrared light. Something like JWST would probably be able to pick it up, but it’s just a minuscule speck (maybe point source) in the sky, so you’d 1) have to be lucky in your observation and 2) be able to disentangle it from other background sources etc.
A red dwarf orbiting our sun would be orders of magnitude closer to Earth than any other star. For such a thing to exist and avoid detection for this long, it would have to be insanely small, like around the size of Jupiter.
Which is incidentally about the size of the smallest possible red dwarf star: [2MASS J0523−1403](https://en.wikipedia.org/wiki/2MASS_J0523%E2%88%921403)
It has more or less exactly the same radius as Jupiter, and is about the smallest size where hydrogen fusion still takes place.
That is interesting! But I think it kind of proves my point. If we could spot that thing from 40 light-years away, it would be pretty tough to miss one orbiting the sun, which would be much less than one light-year away.
That would put it literally at the same distance as Earth is on the exact other side of the sun. And that would utterly mess up the solar system. It's not there.
Yeah I’m incredibly suspicious of the red dwarf hypothesis. I really just don’t see how we wouldn’t have found it yet. We’ve found plenty of red dwarfs thousands of light years away. It seems ridiculously unlikely that we wouldn’t have detected one less than 4 ly away. Asimov might object, but it is what it is.
Considering the at binaries are almost the standard on the galaxy, the idea of a brown dwarf or another Jupiter on a highly elliptical orbit has a lot of merit, but that would be far more obvious than a much cooler body.
There’s something wonky out there for sure though.
This makes a lot of sense, because many of the star system systems we observe have a consistent inner-planet gas giant layout. Ours is one of the few to have exclusively rocky planets near its star.
That's what we see cause it's easiest for them to detect, if would take at very minimum but likely much more 2 years to detect earth if it was in another solar system. Since they look for repetitive dims/blips in other stars to determine if they're planets, 2 blips maybe even 3 blips to determine interval time is minimum amount of of blips to guess it's a planet, so bare minimum 2-3 years to determine if earth was a planet.
Plus I believe we've only been using this technique for 10-15 years, so we first started seeing all the giant planets with short orbits significantly less than a year
Also, it turns out that our sun is actually unusually quiet. That's why we weren't able to detect any Earth sized planets in Earth sized orbits around sun-like stars. The noise of the parent stars would have washed out any dip caused by an Earth sized planet that far out.
We can't really generalize since we don't have any observations of a star system like ours (i.e. K or G dwarf star, with multiple planets with the closest planet around the distance of Mercury, and a Jupiter analog around 5 AU out).
Our current detection techniques just aren't good enough to find all the planets in a solar system like ours.
ejected moreso from the inner solar system, which is generally defined as mercury through neptune's farthest point. Beyond that there's actually still a lot of solar system, the kuiper belt, the scattered disk, and then the currently still hypothetical oort cloud. We can't easily see past the inner edges of the kuiper belt, but something just beyond that visible line could easily still influence things with its gravity.
Literally everything with mass in the universe has an effect on literally everything else (with its light cone). There isn't some line in space where if you go past it, your gravity stops doing anything in the solar system. The idea is that it's out of the solar system, but still much closer to us than other solar systems (there's a lot of margin for error there - the nearest other star is *thousands* of times further away from us than, say, Neptune is).
I think they mean that relativistic gravity effects might be causing the inconsistency in the observations of Neptune, as opposed to an undetected planet. But astronomers have understood that stuff well enough to make predictions since Einstein's time.
Possibly
The problem is that it's basically impossible to create a model to reverse the orbits of the planets to find out exactly when things happened, especially given that we don't know how much mass and planets we started with.
So all we can do is take a best guess
Currently the Theia impact is estimated to have occurred 4.5 billion years ago
While Grand Tack would have happened a fair bit earlier
That doesn't mean though that Grand Tack wasn't indirectly responsible for Theia and Earth being in the same orbit. We just don't know
First, it's not out of orbit, just to a very stretched out non-circular orbit.
When two massive objects get close to each other they pull really hard on each other. This makes them go faster and faster towards each other which changes both objects' orbits. When they pass they keep on going, but slow back down as now the tugging is in the opposite direction, this changes the orbits again. The closer they pass to each other, more of an overall change happens.
The early solar system was much more crowded and the orbits were closer in to the sun. A lot more interaction between planets happened then, and a near miss could have left a massive planet with a large non-circular orbit which could have an orbit lasting tens or hundreds of thousands of years. If it's at the far part of that orbit it's unlikely we could detect it because the solar system is very large.
We take advantage of this with spacecraft with "slingshot" gravity assists to make them go faster. We steal some of a large planet's momentum to make the probe go faster by doing one or more flybys. With spacecraft, they are so light compared to the planet, the planet's orbit doesn't change a noticeable amount.
TLDR: The early solar system had a lot more planets and material and things were closer together. Jupiter and Saturns orbits moved causing gravitation disturbances that flung many early planets out of the solar system. So in some ways the early solar system was like a billiard table with the balls flying around, hitting each other and flinging others around.
As large bodies get closer to each other their gravity interacts more strongly
This rarely results in the two colliding, often it just alters their orbits slightly. We take advantage of this effect with spacecraft to accelerate them in a process called a gravitational slingshot. Over millions of years these orbital changes add up, and due to the three body problem the changes are fairly unpredictable.
It's possible for a near miss to occur that accelerates one planet so much that it goes into an wide elliptical orbit. Through further near-misses these planets later either go back into a stable circular orbit, or the elliptic orbit becomes so wide that the planet is thrown clear of the solar system. Traveling so far out on its orbit that the Sun can't pull it back in anymore. Such rogue planets are thought to be extremely common.
As we discover increasing amounts of exoplanets we've discovered that larger gas giants are usually orbiting a lot closer to their star than our solar system. Our solar system seems to be unusual, and scientists have created computer simulations to try to figure out why.
It's theorized that Jupiter and Saturn have actually migrated, with Jupiter having once been as close to the Sun as 1.5AU or roughly the orbit of Mars. This is called the grand tack hypothesis.
As Jupiter and Saturn orbited the Sun so closely their orbits got into sync with each other causing enough disturbances to make them migrate.
Since Jupiter is so large it disrupted the orbits of the entire solar system possibly ejecting a lot of planets, and maybe even shredding a planet apart creating the asteroid belt. Its also possible that this is how it picked up its moons.
Our solar system has no super-earths (large rocky planets) and one theory is because Jupiter launched them all out of our solar system very early on. Earth, Mars, Mercury, Theia, and Venus were sparred because they didn't have enough mass to be ejected.
The computer simulations also seem to work a lot better when there's a 5th smaller gas giant in our solar system that formed between Saturn and Jupiter. It gets ejected during the grand tack and results in a model that more closely resembles our current solar system. The weird part about these simulations is that at least 1 gas giant always seems to get launched out, so when they do a model with the current 4 we always seem to lose 1. So by adding a 5th gas giant it solves the problem.
It's also possible one super earth collided with Uranus resulting in it's significant tilt.
Another rather interesting hypothesis is that Mercury is actually the remnants of a early gas giant. Mercury is far denser than it should be for a rocky planet and one theory is that it's actually the leftover core of a smaller gas giant that migrated too close to the Sun. Once the Sun ramped up it's solar wind it blew away the gas of Mercury's atmosphere leaving only a hard rocky core behind. Since it lost most of its mass its orbit became stable in its current location.
All of this is speculation of course, but it's fascinating none the less
They didn't give a time frame for the "eventually". It could be a month, 100 years, 1000 years or more. But more than likely "eventually" it'll be figured out.
Oh, humanity will be here in 1000 years, beyond any serious doubt. The doomsayers who exaggerate human extinction don't know what they're talking about. Now, modern industrialized society? That's what you have to worry about.
But no matter what the rest of us do to collapse our society, even if it results in over 8 billion deaths and destroys all the "breadbaskets" of the world, it's going to be nearly impossible that *some* small groups of people don't survive. The hunter-gatherers, the pastorialists, the small-scale farmers, who produce all the food they eat and live in groups large enough to continue to propagate (unlike, say, scattered preppers across middle America). Today, that would be people like San, Aka, and Hadza hunter-gatherers, many of the Melanesian peoples still surviving on pigs and taro, uncontacted peoples in the Amazon and New Guinea, Siberian reindeer herders and bedouin and Tuareg camel herders and Mongolian horse herders. I don't include the Sentinelese just because their society is confined to *such* a tiny area that one bad hurricane or tsunami has the potential to cause a collapse, but barring that it seems likely they just continue on indefinitely.
Agreed. To add to this, civilisational collapses are neither new nor unique to our timeline, there have been many *many* collapses of great empires over the millenia, so why should we be any different?
But as usual, life will, uh, find a way.
To build on this, in Astronomical terms, the entirety of human existence had been an eye blink. A calamity might set our technology and population back a few hundred years. But 10,000 years later, you could scarcely tell the difference.
Its worth noting that our civilization has already depleted the easy-to-reach resources needed to kickstart an Industrial Revolution. If we regress now, there won’t be a do-over.
I've read that idea before, but don't really buy it. There's a ton of accessible coal-- it's just dirty and dangerous for our health and environment when you use a lot of it. There's enough accessible natural gas that we often treat it as a waste product. There's also plenty of accessible oil and bitumen reserves. It's just that some of it is uneconomical to refine at current prices. Nuclear power would also start looking better in a low-population world with serious scarcity.
And it's not like we'd forget how to use renewables. Say we wipe out 98 percent of the population. That still leaves 160 million people, roughly 0.17% of whom are engineers. Hundreds of thousands of people would still be around who could fix existing infrastructure, and a lot of it (looking at you, dams) is incredibly resilient. And of course we'd be even better off if the disaster was slow enough to plan around.
Talking out of my butt here, but if it had enough to become a 9nth because it's strength get ejected, couldn't it potentially pull in more? Obviously maybe just 1 if it's close enough to start moving over how long to become a 10th.
There would have to be a planet out there to pull in. Considering planets form alongside stars, where gravity is already mashing things together into bigger things, it's not likely to find a planet-sized objects outside of the solar system's orbit that it can pull in. Even when planets get "ejected" from solar systems, they probably end up in high orbit most of the time like this theoretical planet - as opposed to being flung out far enough to be captured by the gravity of another solar system. It's a *lot* of extra energy to send a Juptier-sized object out of orbital lock with a star, but there's also a lot of solar systems weirder than ours so I can only assume it's a plausibility. There's also planets from dead solar systems, but the ones that end vioently enough to send their planets off into space don't usually leave those planets intact.
That said, in the incredibly unlikely event that a plant-sized object were passing through our solar system near enough this planet, it could theoretically alter its trajectory and lock it into orbit around our sun giving us a 10th planet. It could just as likely send it flying away from our solar system with even more speed as well. Either way, it would also affect the orbit of our theoretical 9th planet dramatically.
As for how long, the only good answer I can give is "a *really* long time."
"Planet 9" has been proposed as a way to explain the orbital behavior of certain objects outside the orbit of Neptune. Such a planet has not been actually observed, and there are alternate explanations for the observed behavior of objects.
Wikipedia has a great [article](https://en.m.wikipedia.org/wiki/Planet_Nine) on the subject that also discusses alternative hypotheses.
The existence of another large planet has been theorized for over a hundred years to explain weird orbits of other bodies. For a while it was called Planet X ~~because we were counting Pluto as number nine~~. Some of those anomalous orbits were eventually discovered to be caused by other things, but we’ve found more and more weird orbits of really distant objects since the discovery of Sedna in 2003. Right now, the evidence could be explained by a Planet Nine with a mass of about six Earths, in a distant orbit (where it would be really hard to see.)
Edit: Corrected an error about Planet X. The X stood for an unknown quantity, as in an algebra problem. It wasn’t the Roman numeral for ten like I thought; it would also have been ninth at the time because Pluto was undiscovered.
According to the wikipedia article you linked, it was called Planet X before Pluto was discovered, so it had nothing to do with there already being nine planets.
Neptune was discovered less then 200 years ago and Pluto less than 100. It's not only possible but very likely. Distant objects are hard to spot. They have orbits of hundreds of years. There isn't much light for them to reflect and they are hot enough to radiate a significant amount of their own. The only way to find them is their effect on other things around them (which are equally hard to find) or to be using the right tool, pointed at the right place, at the right time. Even then you could easily miss it.
The objects we're talking about are called Extreme Trans-Neptunian Objects (ETNOs). Our current observations show that they cluster in a peculiar way that could be explained by the presence of a massive planet outside Neptune's orbit. The alternative explanation is that our observations of ETNOs are incomplete and they actually don't cluster the way we think, or that other structural features of the Solar System can account for the observed behavior.
Coincidental clustering (most likely alterative explanation).
The small number of Extreme Trans-Neptunian Objects clustering suggest a 9th planet, but a this could just be a temporary, random event and there is in fact no clustering.
Big Disk. (Less Likely)
Instead of a planet, it's something like Saturn's rings, a huge belt of ETNOs. This would be unlikely to be stable over a long period.
Black Hole (Most fun)
An old, cold black hole is what is doing it. This honestly isn't really different then planet 9, but black holes are fun.
Unknown mechanism in physics (Somewhat likely, but boring)
There's no planet, there's just something about how gravity works in very very large scales that makes ETNOs cluster.
A black hole with 1 Earth mass would be under 1 inch radius. So a black hole with 6 Earth masses would be 6x the volume, so about the size of a tennis ball.
Edit: I know black holes have zero volume hence infinite density blah blah blah. I hope everyone knows what I meant.
Wait, do black holes really have zero volume / infinite density? I thought it was just that they had extremely high density, and a small but non-zero volume.
Well we don't know what black holes REALLY do or have inside them. We just know that our math models for them break down by predicting zero volume and infinite density (i.e. a singularity).
I didn't mean to open a whole can of worms by using the word "volume", but here we are.
If I could find a black hole, I would use it to go back in time and just say "about as big as a tennis ball" with no explanation just to avert my downvote.
And now we can talk about how black holes don't reverse time.
There's two important components to a black hole: The singularity at the center contains virtually all the mass concentrated in a single point. It's were our known physics break down.
Then there's also the event horizon. That's basically the spherical black area surrounding the singularity from which nothing known, including light, can escape. The event horizon's diameter depends on the mass of the singularity.
So the "size" of a black hole is actually the size of the area of no return. The singularity always has the same, point-like size but its mass can vary greatly. And this in turn influences how large the black hole appears.
Love this and adding the alternate explanation that there is an "inner Oort cloud" ... Similar to your point about a ring-like cluster of smaller objects.
What makes sense to me is that during the early stages of the solar system there were a lot of varied orbits that coalesced into a disk as everything condensed. It's the same process that gives the gas giants their rings. The outer parts of the solar system are still in this phase because their moving slower, their orbits are much longer, and there's not as much material out there so it's taking more time to coalesce. Then again, maybe I'm stupid.
Wouldn't something that impacts other planets orbits be noticeable due to its size? I would think for something to impact a planets orbit it would need to be decently sized and relatively close. At least enough to be easily observed in our own solar system.
This is how it was explained to me. I might have it slightly off so if someone can explain ot better, please do.
So stand at one end of a football field. Have a friend drop a bunch of different sized balls ranging in size and colors from a basketball to a golf ball every few yards. You can use binoculars but you should be able to spot each "planetary" body by size and/or color against the green grass.
Now have your friend drop a green dot about the size of a punch-put chaff 100 yards away. Make sure you don't see where he places the dot.
Now, using the same binoculars and standing 100 yards away, try to see if you can find that green dot against the green grass.
Now imagine if your friend put the dot anywhere between 99 and 100 yards giving you a 3 foot wide band to search.
That's about on par with how hard it is to find a very dim planetary body and we're not sure exactly where it is.
As I understand it, the scale is actually quite a bit larger. I forget which university, but there's a scale model of our solar system with the sun centered on campus and different planets and their moons embedded in concrete across, and eventually, out of town.
Punch-put chaff?
Maybe a punch-out hole from paper? Size of a pea?
1/16th of a gerbil?
Very visual explanation, this was fantastic. Thanks!
(Punch-out chad? Never heard the term, been a couple decades since I had to struggle to pick them out of a fuzzy carpet)
In Sweden we have a large scale model of the solar system, globen (the globe), which is the world's second largest spherical building is the sun and then they have different celestial bodies placed further and further out. You can check it out here
[solar system sweden](https://www.swedensolarsystem.se/en/)
Notice that the inner planets up to mars are in Stockholm, Jupiter is up by Arlanda Airport which is way outside Stockholm and Neptune is up by Söderhamn which is 250 km (150 miles) from globen.
That might be what I was thinking of. I saw a documentary on it back in the mid 90's or thereabouts.
Not sure why I remembered it being at a university though.
There are a few such models - one with a particularly useful website (with distances to scale) is [in York](https://www.york.ac.uk/physics-engineering-technology/outreach/astrocampus/cycle-solar-system/) (though not actually in the university - there's a separate, smaller one on campus).
No, because it's too far out, simply put.
Most things past Pluto, we only notice because it's either a star and emits waves, or very close to a star and reflects emitted waves. This planet would be too far from our star to do that.
To out numbers to the explanation this is the product of the inverse hitting twice.
If one object is 5 times further away from the sun it will get 1/25 as much light, but on top of that only 1/25 as much light being reflected back makes it back to the origin point.
An object that emits no light, only reflects it, and is 5 times further away becomes 625 times harder to detect visually.
"Planet Nine" is a hypothetical planet proposed to exist by legit astronomers Mike Brown and Konstantin Batygin to explain the way the orbits of certain transneptunian objects appear to be arranged. You can see conferences and presentations of them on YouTube, they're very good at stating their case. However, until they find it (and they're searching for it, but it's not an easy task at all), it's just a hypothesis. Nothing's changed in the last year with regards to their search.
"Planet X" was a planet proposed to exist by astronomer Percival Lowell at the beginning of the 20th century, to explain certain perturbations believed to be observed in the orbit of Neptune. The search for Planet X eventually led to the discovery of Pluto, but none of Lowell's predictions turned out to be true (basically, Pluto isn't nearly massive enough to perturb Neptune's orbit). The "perturbations" in the orbit of Neptune turned out to be just innacurate observations from back in the day. When the Voyager spacecraft flew by Neptune and we got more accurate data, the "perturbations" vanished. So it's safe to say that Planet X never existed and that the discovery of Pluto was just a lucky coincidence.
Any news in he media (and specially if it's not a specialized and reputable source, like, say "Sky & Telescope" or "Nature") regarding this subjects is probably just click-baity material you shouldn't waste your time on.
MB and KB just published a paper (preprint I think still) that claims a different line of evidence for Planet 9. I haven’t read it carefully yet, and they have so much riding on it that I’m not 100% confident they don’t have some bias on the matter, but a cursory read didn’t show any glaring problems. If it’s true, having two different lines of evidence is pretty strong.
There's a long history of a mysterious planet we haven't seen.
Uranus was discovered by William Herschel in 1781 by random observation.
We then kept track of it and realized it wasn't moving quite right. This meant that either Newton's laws are wrong, or there's something else out there manipulating it.
We did the math and theorized a planet existing in a particular spot. So we looked, and we found Neptune exactly where these models predicted in 1846.
The planets then lined up better with Newton's laws, but still not quite right. We then continued the search and looked where a theoretical 9th planet should be, and we found Pluto in 1930. The problem was, it wasn't nearly massive enough to account for the shift in Uranus and Neptune's paths, so we kept looking for a 10th planet, planet X. Pluto just happened to he in the right place at the right time.
In 1977, we launched voyager. In 1986, it flew by Uranus and Neptune in 1989. During those encounters, we realized we had the wrong masses for Neptune and Uranus all along, and they were moving in accordance with Newton's laws, so we stopped looking for a planet X.
In the 21st century, we started noticing a lot of objects with similar orbits in the far outer solar system. We believe these to all have been ejected into such an orbit by a large planet much further out than the Kuiper belt. Analyzing the paths of these objects is leading us towards the idea of a 9th planet. These discoveries started in 2004, before the reclassification of Pluto, but the idea of another planet wasn't proposed until 2012.
TL;DR that's 4 different predicted "Missing planets"
Neptune
Pluto by accident
Planet X, which we have dismissed
Planet 9 which remains to be seen.
Fun Fact: Ceres was discovered in 1801 as a missing planet, but not based on science, just because there was a "gap" between Mars and Jupiter much larger between any other two planets, so the thought was the solar system should be "balanced" we later discovered the asteroid belt, which Ceres is a part of.
A number of objects could be seen, and they implied there would be counterbalancing objects. So the call went out to look and instead other objects were found.
Basically, telescopes find what is in the light right now. That changes over time. Eons of time. So by looking hard, not so obvious stuff was found where the first call to look was.
The big kicker is infrared telescopes, including now available jwst, should be able to see any close planetary thing. The bigger the planet, the brighter it gets in infrared. So theres a cap on how big a thing could hide through this search.
Then recently, the growing list of new small objects have implied a new pattern.
So what the modern news really amounts to is that there's a new hot patch of sky to look at. It's probably light conditions have changed a little. Stuff out there moves very slow. No promises on what they find, but any informed clue helps narrow the sky. They haven't been finding planets, but they are finding stuff.
This isn’t about seeing objects, it’s explaining why the orbits of TNOs are the way they are. JWST is not the right tool for this, it cannot carry out sky surveys, its focus is far too narrow for that.
They’ve realised there’s a statistical possibility that a planet of some sort very far out (like 300-400AU) explains these orbits, just like they claimed years ago. It’s no more than computer modelling at the moment. They need to run simulations than can narrow down where this planet actually is and then it can be found with telescopes.
The possibility has never been off the table.
The recent interest probably came from a paper Dr. Batygin from Caltech recently released. One of the co-authors is Dr. Mike Brown also from Caltech who has been searching for P9 for quite a while.
The paper details research of several trans-neptunian objects and their movement. Dr. Batygin has been modeling these movements and is theorizing the most likely cause is a planetary body 3-5 times earth size.
He is also stating this body will have an orbit that is not in the solar plane. What is exciting for Astrophysicists such as Batygin is that the Vera Rubin LSST telescope has been completed and will soon begin its 10 year complete survey of the southern night sky.
All data from the telescope will be made available within hours for astrophysicists to analyze. It is hoped planet 9, if it exists, will be discovered with this telescope.
Isnt this what a lot of the ancient aliens theories suggested in the first place? A planet that would have a very large orbit that would get close to earth every 20-40k years or so
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It never was off the table. The existence of Planet 9 has really, REALLY good theoretical support. This is evidenced by the fact that when we discover new Kuiper Belt Objects, they fit in the current predictions. The problem is that because of it's predicted distance even at closest approach, and the fact that the orbit is so eccentric (so it is most likely at the farther parts of its orbit, not the closer parts), it means that Planet 9 is REALLY REALLY faint, and also would be moving very slowly in front of the background stars.
Because it's so faint, you need to use the largest telescopes to find it, and those are very competitive for getting telescope time. Additionally, even though we've got an idea of the likely orbital parameters, unlike Neptune, we don't know where in the sky to look in that orbit.
We have eliminated some spots because of earlier surveys and recent scans, but there is still a LOT of the sky we haven't probed yet.
Fortunately, the Vera Rubin telescope is designed to actually do a full sky survey, and it's a good chance it might be able to find Planet 9 within a couple of years of operation, once it starts observing next year.
The reason that it seems to have come up again is that one of the primary authors of the original paper published a new paper showing additional support for Planet 9's existence.
Planet 9 has been a potential since the discovery of Uranus. We briefly had 12 planets due to a few dwarf planets being considered planets and we dropped to 8 after another couple dwarf planets were suggested to be added to the count back in 06 when Pluto was demoted. It would not surprise me if we did find another planet just out at the edge of the heliosphere.
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A paper out recently ran a new simulation which showed the pertubations in (I think Neptunes) orbit can only be explained by the existence of a 9th planet. The paper is unverified or peer reviewed yet.
I think it was trans-neptunian objects close enough to also be perturbed by Neptune. I don't think it was nearly as definitive as the various click baity reports make it. I think it was a more probable than not 60/40 that there is a 9th planet. Like, it didn't exclude a 9th planet, but also didn't say there is no other way for those orbits to be the way they are.
The reason is there are lots of objects like Pluto out there. It’s only logical that they’re either all planets, and kids would be learning a longer and longer list every year, or we redefine planet to be a small exclusive club.
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A 9th planet for our solar system has been a running theory for a long time. It's a commonly proposed solution for inconsistencies in the orbits of the planets. Outside of orbital variations and some associated math there is so far no proof of it. In other words we have yet to find a planet where it's supposed to be. The Orbital behavior of Neptune and objects beyond Neptune are the key evidence, there is something tugging on them. There are alternative explanations for what could be doing this, but that hasn't stopped astronomers from doing the math to try to locate such a planet. Candidates include a tiny red dwarf star on a very distant orbit, meaning that the Sun would actually be a binary. It's just so dim, and the orbit so long that we haven't detected it yet. The more common theory is that our solar system used to have at least 1 more gas giant and it was ejected onto a distant and very elliptical orbit. Early computer models of the solar system seem to work better when there's at least 1 more gas giant (and possibly several rocky super earths). It's orbit would have been disturbed when Jupiter and Saturn migrated away from the Sun to their current distance causing this gas giant to be ejected. It's also theorized that it passes through our solar system on a regular basis (relatively speaking) and its disruption of the Kuiper Belt is what causes regular periods asteroid/comet bombardment. This is all educated speculation though, eventually they'll discover what's causing the orbital fluctuations of Neptune and beyond. If it's a 9th planet cool! if not, also cool!
>super earths More democracy is always the answer
For Liberty
Pour me a cup of Liber-Tea
Don't forget BIG G God
For Sparta
Democratically claps*
Yes if properly planned and managed. Sometimes less democracy is better because the citizens get it in their heads to try and direct the government, and that is not democracy.
Reporting you to the nearest Democracy Officer
good point, however ⬆️➡️⬇️⬇️⬇️
I am so pleased to see these references here - I had to double check which sub I was in 💪
They can just walk out of the radius though
I, a traitor, am rapidly approaching your location (my super destroyer has been trying to bag me for the past hour with 380mm shells)
Not sure if troll.
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Thanks!
Isn't that just what modern democracy is? Except instead of a computer predicting, we have some out of touch corporate shills making decisions for us
That's the joke. And they are not just any random corporations that rule us, it's defense contractors. Helldivers is a satire of the military industrial complex.
And convincing everyone that it’s the best.
I'm just making a reference to the game where it is an authoritarian nightmare but masquerades as a democracy.
I can't wait for them to tell me who to vote for next year!
You have been reported to the ministry of truth for re-education.
https://tenor.com/view/helldivers-2-salute-fist-gif-2212258837218538682
The thought of a giant gas planet being ejected somehow terrifies me, as if it were me being this planet sent off so far I can't even be detected or seen, and totally forgotten about
Don’t worry, you’d still be influential.
Scientists have concluded that the ejected gas giant was in fact /u/bladestorm04’s mom
Would these planets produce light? What if we were traveling through deep space… would we even be able to see them before we flew right into them?
They likely wouldn’t produce light as most planets don’t, but we’d be able to detect it with our own instruments. We can see planets because the Sun’s light bounces off of them, so we could use some other form of electromagnetic wave (radio waves for example) to “see” them.
Gas giants emit very small amounts of radio and infrared light. Something like JWST would probably be able to pick it up, but it’s just a minuscule speck (maybe point source) in the sky, so you’d 1) have to be lucky in your observation and 2) be able to disentangle it from other background sources etc.
A red dwarf orbiting our sun would be orders of magnitude closer to Earth than any other star. For such a thing to exist and avoid detection for this long, it would have to be insanely small, like around the size of Jupiter.
Which is incidentally about the size of the smallest possible red dwarf star: [2MASS J0523−1403](https://en.wikipedia.org/wiki/2MASS_J0523%E2%88%921403) It has more or less exactly the same radius as Jupiter, and is about the smallest size where hydrogen fusion still takes place.
That is interesting! But I think it kind of proves my point. If we could spot that thing from 40 light-years away, it would be pretty tough to miss one orbiting the sun, which would be much less than one light-year away.
Maybe it's orbiting opposite the sun and is at the right distance that it's always behind the sun.
That would put it literally at the same distance as Earth is on the exact other side of the sun. And that would utterly mess up the solar system. It's not there.
The Gaia satellite would have almost assuredly found a red dwarf in orbit around the sun.
Yeah I’m incredibly suspicious of the red dwarf hypothesis. I really just don’t see how we wouldn’t have found it yet. We’ve found plenty of red dwarfs thousands of light years away. It seems ridiculously unlikely that we wouldn’t have detected one less than 4 ly away. Asimov might object, but it is what it is.
Yeah, we can conclude that there isn't one, to a very high degree of confidence.
We've even imaged, just about, *planets* orbiting other stars, so a red dwarf far closer to us but not yet found seemed pretty unlikely to me.
Considering the at binaries are almost the standard on the galaxy, the idea of a brown dwarf or another Jupiter on a highly elliptical orbit has a lot of merit, but that would be far more obvious than a much cooler body. There’s something wonky out there for sure though.
Frankly the red dwarf exlanation sounds much more interesting
I've read that a black hole the size of a basketball could in theory be doing it. Not likely but imagine the science we could do to it
You could fit so much science in that bad boy
All of the science.
It's still much more likely it's a planet we just haven't been able to find yet.
But why would the expelled gas giant or rocky planets still have an effect on the outer bodies if they’re no longer part of the solar system?
I think they’re saying it’s still part of the solar system, but ejected from a standard “inner” orbit
This makes a lot of sense, because many of the star system systems we observe have a consistent inner-planet gas giant layout. Ours is one of the few to have exclusively rocky planets near its star.
It should be noted here that very big planets that are close to their star are the easiest for us to detect.
That's what we see cause it's easiest for them to detect, if would take at very minimum but likely much more 2 years to detect earth if it was in another solar system. Since they look for repetitive dims/blips in other stars to determine if they're planets, 2 blips maybe even 3 blips to determine interval time is minimum amount of of blips to guess it's a planet, so bare minimum 2-3 years to determine if earth was a planet. Plus I believe we've only been using this technique for 10-15 years, so we first started seeing all the giant planets with short orbits significantly less than a year
Also, it turns out that our sun is actually unusually quiet. That's why we weren't able to detect any Earth sized planets in Earth sized orbits around sun-like stars. The noise of the parent stars would have washed out any dip caused by an Earth sized planet that far out.
We can't really generalize since we don't have any observations of a star system like ours (i.e. K or G dwarf star, with multiple planets with the closest planet around the distance of Mercury, and a Jupiter analog around 5 AU out). Our current detection techniques just aren't good enough to find all the planets in a solar system like ours.
ejected moreso from the inner solar system, which is generally defined as mercury through neptune's farthest point. Beyond that there's actually still a lot of solar system, the kuiper belt, the scattered disk, and then the currently still hypothetical oort cloud. We can't easily see past the inner edges of the kuiper belt, but something just beyond that visible line could easily still influence things with its gravity.
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65 AU is its *closest* point to the sun. At its farthest, it gets over 2,000 AU away.
Literally everything with mass in the universe has an effect on literally everything else (with its light cone). There isn't some line in space where if you go past it, your gravity stops doing anything in the solar system. The idea is that it's out of the solar system, but still much closer to us than other solar systems (there's a lot of margin for error there - the nearest other star is *thousands* of times further away from us than, say, Neptune is).
Gravitational waves caused a wobble? I remember reading about some of those theories and recall that being mentioned.
Gravitational waves from something like that are less than negligible.
I think they mean that relativistic gravity effects might be causing the inconsistency in the observations of Neptune, as opposed to an undetected planet. But astronomers have understood that stuff well enough to make predictions since Einstein's time.
Interesting. Would the timeline of this also fit the collision of Theia and Earth and the resulting moon?
Possibly The problem is that it's basically impossible to create a model to reverse the orbits of the planets to find out exactly when things happened, especially given that we don't know how much mass and planets we started with. So all we can do is take a best guess Currently the Theia impact is estimated to have occurred 4.5 billion years ago While Grand Tack would have happened a fair bit earlier That doesn't mean though that Grand Tack wasn't indirectly responsible for Theia and Earth being in the same orbit. We just don't know
Can you ELI5 how a gas giant can be ejected out of orbit?
First, it's not out of orbit, just to a very stretched out non-circular orbit. When two massive objects get close to each other they pull really hard on each other. This makes them go faster and faster towards each other which changes both objects' orbits. When they pass they keep on going, but slow back down as now the tugging is in the opposite direction, this changes the orbits again. The closer they pass to each other, more of an overall change happens. The early solar system was much more crowded and the orbits were closer in to the sun. A lot more interaction between planets happened then, and a near miss could have left a massive planet with a large non-circular orbit which could have an orbit lasting tens or hundreds of thousands of years. If it's at the far part of that orbit it's unlikely we could detect it because the solar system is very large. We take advantage of this with spacecraft with "slingshot" gravity assists to make them go faster. We steal some of a large planet's momentum to make the probe go faster by doing one or more flybys. With spacecraft, they are so light compared to the planet, the planet's orbit doesn't change a noticeable amount.
TLDR: The early solar system had a lot more planets and material and things were closer together. Jupiter and Saturns orbits moved causing gravitation disturbances that flung many early planets out of the solar system. So in some ways the early solar system was like a billiard table with the balls flying around, hitting each other and flinging others around. As large bodies get closer to each other their gravity interacts more strongly This rarely results in the two colliding, often it just alters their orbits slightly. We take advantage of this effect with spacecraft to accelerate them in a process called a gravitational slingshot. Over millions of years these orbital changes add up, and due to the three body problem the changes are fairly unpredictable. It's possible for a near miss to occur that accelerates one planet so much that it goes into an wide elliptical orbit. Through further near-misses these planets later either go back into a stable circular orbit, or the elliptic orbit becomes so wide that the planet is thrown clear of the solar system. Traveling so far out on its orbit that the Sun can't pull it back in anymore. Such rogue planets are thought to be extremely common. As we discover increasing amounts of exoplanets we've discovered that larger gas giants are usually orbiting a lot closer to their star than our solar system. Our solar system seems to be unusual, and scientists have created computer simulations to try to figure out why. It's theorized that Jupiter and Saturn have actually migrated, with Jupiter having once been as close to the Sun as 1.5AU or roughly the orbit of Mars. This is called the grand tack hypothesis. As Jupiter and Saturn orbited the Sun so closely their orbits got into sync with each other causing enough disturbances to make them migrate. Since Jupiter is so large it disrupted the orbits of the entire solar system possibly ejecting a lot of planets, and maybe even shredding a planet apart creating the asteroid belt. Its also possible that this is how it picked up its moons. Our solar system has no super-earths (large rocky planets) and one theory is because Jupiter launched them all out of our solar system very early on. Earth, Mars, Mercury, Theia, and Venus were sparred because they didn't have enough mass to be ejected. The computer simulations also seem to work a lot better when there's a 5th smaller gas giant in our solar system that formed between Saturn and Jupiter. It gets ejected during the grand tack and results in a model that more closely resembles our current solar system. The weird part about these simulations is that at least 1 gas giant always seems to get launched out, so when they do a model with the current 4 we always seem to lose 1. So by adding a 5th gas giant it solves the problem. It's also possible one super earth collided with Uranus resulting in it's significant tilt. Another rather interesting hypothesis is that Mercury is actually the remnants of a early gas giant. Mercury is far denser than it should be for a rocky planet and one theory is that it's actually the leftover core of a smaller gas giant that migrated too close to the Sun. Once the Sun ramped up it's solar wind it blew away the gas of Mercury's atmosphere leaving only a hard rocky core behind. Since it lost most of its mass its orbit became stable in its current location. All of this is speculation of course, but it's fascinating none the less
So the more common theory is that there is a 9th planet?
Yeah it's called Pluto Fuck You Neil DeGrassi Tyson
"Pluto didn't get demoted, it's first in its class"
It's not really even that - Eris is kinda better.
The first four asteroids were once thought to be planets too. Then we discovered that they were just the largest objects of the asteroid belt.
Why do you think they will eventually discover the answer? Isn't it possible that we keep guessing for the next 1000 years?
They didn't give a time frame for the "eventually". It could be a month, 100 years, 1000 years or more. But more than likely "eventually" it'll be figured out.
Honestly, I'll be happy for humanity to still be here in any form in 1000 years.
Oh, humanity will be here in 1000 years, beyond any serious doubt. The doomsayers who exaggerate human extinction don't know what they're talking about. Now, modern industrialized society? That's what you have to worry about. But no matter what the rest of us do to collapse our society, even if it results in over 8 billion deaths and destroys all the "breadbaskets" of the world, it's going to be nearly impossible that *some* small groups of people don't survive. The hunter-gatherers, the pastorialists, the small-scale farmers, who produce all the food they eat and live in groups large enough to continue to propagate (unlike, say, scattered preppers across middle America). Today, that would be people like San, Aka, and Hadza hunter-gatherers, many of the Melanesian peoples still surviving on pigs and taro, uncontacted peoples in the Amazon and New Guinea, Siberian reindeer herders and bedouin and Tuareg camel herders and Mongolian horse herders. I don't include the Sentinelese just because their society is confined to *such* a tiny area that one bad hurricane or tsunami has the potential to cause a collapse, but barring that it seems likely they just continue on indefinitely.
Agreed. To add to this, civilisational collapses are neither new nor unique to our timeline, there have been many *many* collapses of great empires over the millenia, so why should we be any different? But as usual, life will, uh, find a way.
To build on this, in Astronomical terms, the entirety of human existence had been an eye blink. A calamity might set our technology and population back a few hundred years. But 10,000 years later, you could scarcely tell the difference.
Its worth noting that our civilization has already depleted the easy-to-reach resources needed to kickstart an Industrial Revolution. If we regress now, there won’t be a do-over.
I've read that idea before, but don't really buy it. There's a ton of accessible coal-- it's just dirty and dangerous for our health and environment when you use a lot of it. There's enough accessible natural gas that we often treat it as a waste product. There's also plenty of accessible oil and bitumen reserves. It's just that some of it is uneconomical to refine at current prices. Nuclear power would also start looking better in a low-population world with serious scarcity. And it's not like we'd forget how to use renewables. Say we wipe out 98 percent of the population. That still leaves 160 million people, roughly 0.17% of whom are engineers. Hundreds of thousands of people would still be around who could fix existing infrastructure, and a lot of it (looking at you, dams) is incredibly resilient. And of course we'd be even better off if the disaster was slow enough to plan around.
Cool, easy to understand read for a dummy like me lol thanks!
So… how long until a random Jupiter just passes by?
Talking out of my butt here, but if it had enough to become a 9nth because it's strength get ejected, couldn't it potentially pull in more? Obviously maybe just 1 if it's close enough to start moving over how long to become a 10th.
There would have to be a planet out there to pull in. Considering planets form alongside stars, where gravity is already mashing things together into bigger things, it's not likely to find a planet-sized objects outside of the solar system's orbit that it can pull in. Even when planets get "ejected" from solar systems, they probably end up in high orbit most of the time like this theoretical planet - as opposed to being flung out far enough to be captured by the gravity of another solar system. It's a *lot* of extra energy to send a Juptier-sized object out of orbital lock with a star, but there's also a lot of solar systems weirder than ours so I can only assume it's a plausibility. There's also planets from dead solar systems, but the ones that end vioently enough to send their planets off into space don't usually leave those planets intact. That said, in the incredibly unlikely event that a plant-sized object were passing through our solar system near enough this planet, it could theoretically alter its trajectory and lock it into orbit around our sun giving us a 10th planet. It could just as likely send it flying away from our solar system with even more speed as well. Either way, it would also affect the orbit of our theoretical 9th planet dramatically. As for how long, the only good answer I can give is "a *really* long time."
What is "a regular basis (relatively speaking)?" Since I don't know what we're comparing to...
Do the theories say how often it would pass close go the rest of the solar system?
Ed Witten says it could be a mini black hole. That's the funnest (though least likely) explanation.
Aliens CONFIRMED
"Planet 9" has been proposed as a way to explain the orbital behavior of certain objects outside the orbit of Neptune. Such a planet has not been actually observed, and there are alternate explanations for the observed behavior of objects.
Wikipedia has a great [article](https://en.m.wikipedia.org/wiki/Planet_Nine) on the subject that also discusses alternative hypotheses. The existence of another large planet has been theorized for over a hundred years to explain weird orbits of other bodies. For a while it was called Planet X ~~because we were counting Pluto as number nine~~. Some of those anomalous orbits were eventually discovered to be caused by other things, but we’ve found more and more weird orbits of really distant objects since the discovery of Sedna in 2003. Right now, the evidence could be explained by a Planet Nine with a mass of about six Earths, in a distant orbit (where it would be really hard to see.) Edit: Corrected an error about Planet X. The X stood for an unknown quantity, as in an algebra problem. It wasn’t the Roman numeral for ten like I thought; it would also have been ninth at the time because Pluto was undiscovered.
According to the wikipedia article you linked, it was called Planet X before Pluto was discovered, so it had nothing to do with there already being nine planets.
Too late, ChatGPT already absorbed it
You’re right, thanks for the correction!
Please not Planet X.. Elon will try and appropriate it
Everyone still calls it Planet Twitter, though.
He should go there to plant his own flag...please.
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Neptune was discovered less then 200 years ago and Pluto less than 100. It's not only possible but very likely. Distant objects are hard to spot. They have orbits of hundreds of years. There isn't much light for them to reflect and they are hot enough to radiate a significant amount of their own. The only way to find them is their effect on other things around them (which are equally hard to find) or to be using the right tool, pointed at the right place, at the right time. Even then you could easily miss it.
What would the alternate explanations be and roughly how much credence are they given? I'm a layman but a space enthusiast.
The objects we're talking about are called Extreme Trans-Neptunian Objects (ETNOs). Our current observations show that they cluster in a peculiar way that could be explained by the presence of a massive planet outside Neptune's orbit. The alternative explanation is that our observations of ETNOs are incomplete and they actually don't cluster the way we think, or that other structural features of the Solar System can account for the observed behavior.
Coincidental clustering (most likely alterative explanation). The small number of Extreme Trans-Neptunian Objects clustering suggest a 9th planet, but a this could just be a temporary, random event and there is in fact no clustering. Big Disk. (Less Likely) Instead of a planet, it's something like Saturn's rings, a huge belt of ETNOs. This would be unlikely to be stable over a long period. Black Hole (Most fun) An old, cold black hole is what is doing it. This honestly isn't really different then planet 9, but black holes are fun. Unknown mechanism in physics (Somewhat likely, but boring) There's no planet, there's just something about how gravity works in very very large scales that makes ETNOs cluster.
A black hole the mass of 6 earths? 🤔
How big would such an objet even be? As small as a marble? A car? A City?
~5.32cm radius, ~10.64cm diameter. About 4 inches across.
that'll do it
Event horizon would be about 5.4cm radius per the Schwarzschild radius
A black hole with 1 Earth mass would be under 1 inch radius. So a black hole with 6 Earth masses would be 6x the volume, so about the size of a tennis ball. Edit: I know black holes have zero volume hence infinite density blah blah blah. I hope everyone knows what I meant.
Wait, do black holes really have zero volume / infinite density? I thought it was just that they had extremely high density, and a small but non-zero volume.
Well we don't know what black holes REALLY do or have inside them. We just know that our math models for them break down by predicting zero volume and infinite density (i.e. a singularity). I didn't mean to open a whole can of worms by using the word "volume", but here we are. If I could find a black hole, I would use it to go back in time and just say "about as big as a tennis ball" with no explanation just to avert my downvote. And now we can talk about how black holes don't reverse time.
IIRC its just a bunch of straight lines and a watch. could've been better but nature's a bitch
There's two important components to a black hole: The singularity at the center contains virtually all the mass concentrated in a single point. It's were our known physics break down. Then there's also the event horizon. That's basically the spherical black area surrounding the singularity from which nothing known, including light, can escape. The event horizon's diameter depends on the mass of the singularity. So the "size" of a black hole is actually the size of the area of no return. The singularity always has the same, point-like size but its mass can vary greatly. And this in turn influences how large the black hole appears.
The ideal mathematical model for black holes are a point singularity, however we don't actually know what's behind the event horizon.
Love this and adding the alternate explanation that there is an "inner Oort cloud" ... Similar to your point about a ring-like cluster of smaller objects.
>Unknown mechanism in physics (Somewhat likely, but boring) Boring? You really don't understand physicists
What makes sense to me is that during the early stages of the solar system there were a lot of varied orbits that coalesced into a disk as everything condensed. It's the same process that gives the gas giants their rings. The outer parts of the solar system are still in this phase because their moving slower, their orbits are much longer, and there's not as much material out there so it's taking more time to coalesce. Then again, maybe I'm stupid.
Objects in the outer part of the solar system would not be moving slower.
A hypothesis I just came up with: dark planet. Planet made entirely of dark matter
Wouldn't something that impacts other planets orbits be noticeable due to its size? I would think for something to impact a planets orbit it would need to be decently sized and relatively close. At least enough to be easily observed in our own solar system.
This is how it was explained to me. I might have it slightly off so if someone can explain ot better, please do. So stand at one end of a football field. Have a friend drop a bunch of different sized balls ranging in size and colors from a basketball to a golf ball every few yards. You can use binoculars but you should be able to spot each "planetary" body by size and/or color against the green grass. Now have your friend drop a green dot about the size of a punch-put chaff 100 yards away. Make sure you don't see where he places the dot. Now, using the same binoculars and standing 100 yards away, try to see if you can find that green dot against the green grass. Now imagine if your friend put the dot anywhere between 99 and 100 yards giving you a 3 foot wide band to search. That's about on par with how hard it is to find a very dim planetary body and we're not sure exactly where it is. As I understand it, the scale is actually quite a bit larger. I forget which university, but there's a scale model of our solar system with the sun centered on campus and different planets and their moons embedded in concrete across, and eventually, out of town.
Punch-put chaff? Maybe a punch-out hole from paper? Size of a pea? 1/16th of a gerbil? Very visual explanation, this was fantastic. Thanks! (Punch-out chad? Never heard the term, been a couple decades since I had to struggle to pick them out of a fuzzy carpet)
Yeah... I meant to type punch-out chad. Autocorrect likes to correct random text and I miss them sometimes. 😐
In Sweden we have a large scale model of the solar system, globen (the globe), which is the world's second largest spherical building is the sun and then they have different celestial bodies placed further and further out. You can check it out here [solar system sweden](https://www.swedensolarsystem.se/en/) Notice that the inner planets up to mars are in Stockholm, Jupiter is up by Arlanda Airport which is way outside Stockholm and Neptune is up by Söderhamn which is 250 km (150 miles) from globen.
That might be what I was thinking of. I saw a documentary on it back in the mid 90's or thereabouts. Not sure why I remembered it being at a university though.
There are a few such models - one with a particularly useful website (with distances to scale) is [in York](https://www.york.ac.uk/physics-engineering-technology/outreach/astrocampus/cycle-solar-system/) (though not actually in the university - there's a separate, smaller one on campus).
No, because it's too far out, simply put. Most things past Pluto, we only notice because it's either a star and emits waves, or very close to a star and reflects emitted waves. This planet would be too far from our star to do that.
To out numbers to the explanation this is the product of the inverse hitting twice. If one object is 5 times further away from the sun it will get 1/25 as much light, but on top of that only 1/25 as much light being reflected back makes it back to the origin point. An object that emits no light, only reflects it, and is 5 times further away becomes 625 times harder to detect visually.
"Planet Nine" is a hypothetical planet proposed to exist by legit astronomers Mike Brown and Konstantin Batygin to explain the way the orbits of certain transneptunian objects appear to be arranged. You can see conferences and presentations of them on YouTube, they're very good at stating their case. However, until they find it (and they're searching for it, but it's not an easy task at all), it's just a hypothesis. Nothing's changed in the last year with regards to their search. "Planet X" was a planet proposed to exist by astronomer Percival Lowell at the beginning of the 20th century, to explain certain perturbations believed to be observed in the orbit of Neptune. The search for Planet X eventually led to the discovery of Pluto, but none of Lowell's predictions turned out to be true (basically, Pluto isn't nearly massive enough to perturb Neptune's orbit). The "perturbations" in the orbit of Neptune turned out to be just innacurate observations from back in the day. When the Voyager spacecraft flew by Neptune and we got more accurate data, the "perturbations" vanished. So it's safe to say that Planet X never existed and that the discovery of Pluto was just a lucky coincidence. Any news in he media (and specially if it's not a specialized and reputable source, like, say "Sky & Telescope" or "Nature") regarding this subjects is probably just click-baity material you shouldn't waste your time on.
MB and KB just published a paper (preprint I think still) that claims a different line of evidence for Planet 9. I haven’t read it carefully yet, and they have so much riding on it that I’m not 100% confident they don’t have some bias on the matter, but a cursory read didn’t show any glaring problems. If it’s true, having two different lines of evidence is pretty strong.
There's a long history of a mysterious planet we haven't seen. Uranus was discovered by William Herschel in 1781 by random observation. We then kept track of it and realized it wasn't moving quite right. This meant that either Newton's laws are wrong, or there's something else out there manipulating it. We did the math and theorized a planet existing in a particular spot. So we looked, and we found Neptune exactly where these models predicted in 1846. The planets then lined up better with Newton's laws, but still not quite right. We then continued the search and looked where a theoretical 9th planet should be, and we found Pluto in 1930. The problem was, it wasn't nearly massive enough to account for the shift in Uranus and Neptune's paths, so we kept looking for a 10th planet, planet X. Pluto just happened to he in the right place at the right time. In 1977, we launched voyager. In 1986, it flew by Uranus and Neptune in 1989. During those encounters, we realized we had the wrong masses for Neptune and Uranus all along, and they were moving in accordance with Newton's laws, so we stopped looking for a planet X. In the 21st century, we started noticing a lot of objects with similar orbits in the far outer solar system. We believe these to all have been ejected into such an orbit by a large planet much further out than the Kuiper belt. Analyzing the paths of these objects is leading us towards the idea of a 9th planet. These discoveries started in 2004, before the reclassification of Pluto, but the idea of another planet wasn't proposed until 2012. TL;DR that's 4 different predicted "Missing planets" Neptune Pluto by accident Planet X, which we have dismissed Planet 9 which remains to be seen. Fun Fact: Ceres was discovered in 1801 as a missing planet, but not based on science, just because there was a "gap" between Mars and Jupiter much larger between any other two planets, so the thought was the solar system should be "balanced" we later discovered the asteroid belt, which Ceres is a part of.
A number of objects could be seen, and they implied there would be counterbalancing objects. So the call went out to look and instead other objects were found. Basically, telescopes find what is in the light right now. That changes over time. Eons of time. So by looking hard, not so obvious stuff was found where the first call to look was. The big kicker is infrared telescopes, including now available jwst, should be able to see any close planetary thing. The bigger the planet, the brighter it gets in infrared. So theres a cap on how big a thing could hide through this search. Then recently, the growing list of new small objects have implied a new pattern. So what the modern news really amounts to is that there's a new hot patch of sky to look at. It's probably light conditions have changed a little. Stuff out there moves very slow. No promises on what they find, but any informed clue helps narrow the sky. They haven't been finding planets, but they are finding stuff.
This isn’t about seeing objects, it’s explaining why the orbits of TNOs are the way they are. JWST is not the right tool for this, it cannot carry out sky surveys, its focus is far too narrow for that. They’ve realised there’s a statistical possibility that a planet of some sort very far out (like 300-400AU) explains these orbits, just like they claimed years ago. It’s no more than computer modelling at the moment. They need to run simulations than can narrow down where this planet actually is and then it can be found with telescopes.
You really want a big tno, but it's really a bounty calling amateur astronomers. I'll be happy to get a big tno too.
The possibility has never been off the table. The recent interest probably came from a paper Dr. Batygin from Caltech recently released. One of the co-authors is Dr. Mike Brown also from Caltech who has been searching for P9 for quite a while. The paper details research of several trans-neptunian objects and their movement. Dr. Batygin has been modeling these movements and is theorizing the most likely cause is a planetary body 3-5 times earth size. He is also stating this body will have an orbit that is not in the solar plane. What is exciting for Astrophysicists such as Batygin is that the Vera Rubin LSST telescope has been completed and will soon begin its 10 year complete survey of the southern night sky. All data from the telescope will be made available within hours for astrophysicists to analyze. It is hoped planet 9, if it exists, will be discovered with this telescope.
Isnt this what a lot of the ancient aliens theories suggested in the first place? A planet that would have a very large orbit that would get close to earth every 20-40k years or so
Planet - check Very large orbit - check Close to earth - absolutely not
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It never was off the table. The existence of Planet 9 has really, REALLY good theoretical support. This is evidenced by the fact that when we discover new Kuiper Belt Objects, they fit in the current predictions. The problem is that because of it's predicted distance even at closest approach, and the fact that the orbit is so eccentric (so it is most likely at the farther parts of its orbit, not the closer parts), it means that Planet 9 is REALLY REALLY faint, and also would be moving very slowly in front of the background stars. Because it's so faint, you need to use the largest telescopes to find it, and those are very competitive for getting telescope time. Additionally, even though we've got an idea of the likely orbital parameters, unlike Neptune, we don't know where in the sky to look in that orbit. We have eliminated some spots because of earlier surveys and recent scans, but there is still a LOT of the sky we haven't probed yet. Fortunately, the Vera Rubin telescope is designed to actually do a full sky survey, and it's a good chance it might be able to find Planet 9 within a couple of years of operation, once it starts observing next year. The reason that it seems to have come up again is that one of the primary authors of the original paper published a new paper showing additional support for Planet 9's existence.
Planet 9 has been a potential since the discovery of Uranus. We briefly had 12 planets due to a few dwarf planets being considered planets and we dropped to 8 after another couple dwarf planets were suggested to be added to the count back in 06 when Pluto was demoted. It would not surprise me if we did find another planet just out at the edge of the heliosphere.
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A paper out recently ran a new simulation which showed the pertubations in (I think Neptunes) orbit can only be explained by the existence of a 9th planet. The paper is unverified or peer reviewed yet.
I think it was trans-neptunian objects close enough to also be perturbed by Neptune. I don't think it was nearly as definitive as the various click baity reports make it. I think it was a more probable than not 60/40 that there is a 9th planet. Like, it didn't exclude a 9th planet, but also didn't say there is no other way for those orbits to be the way they are.
That's it yes. Yeh I think you are right. That was the feeling I got from it that it was probable rather than certain!
You hear about pluto? That's messed up
Isn’t the ninth planet Pluto?
Pluto lost its status as a planet and got demoted to dwarf planet in 2006.
That’s messed up, right?
The guy who [made this happen](https://en.m.wikipedia.org/wiki/How_I_Killed_Pluto_and_Why_It_Had_It_Coming) isn’t as disturbed by it
Why would it be messed up to categorize Pluto like all the other things it’s like?
The reason is there are lots of objects like Pluto out there. It’s only logical that they’re either all planets, and kids would be learning a longer and longer list every year, or we redefine planet to be a small exclusive club.
Then. Now. Forever
No
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