Astronomers Create 'Treasure Map' To Find Proposed Planet Nine (extremetech.com) 95
Some scientists believe there is a ninth planet lurking out there in the inky blackness at the edge of the solar system. A new analysis (PDF) supports the notion that there's something out there, and it also narrows the region we need to search if we want to find the contentious Planet Nine. ExtremeTech reports: Astronomers started talking seriously about a ninth planet in 2016 when Caltech's Mike Brown and Konstantin Batygin published a study detailing the unusual orbital behavior of Kuiper Belt Objects (KBOs). These icy chunks of rock orbit the sun out beyond the orbit of Neptune. Pluto might not be a planet anymore, but it was the first KBO ever discovered. According to the original study, the uneven distribution of orbits among KBOs points to the presence of a massive object in the outer solar system. All searches for this planet have come up empty, though. While some astronomers believe Planet Nine is a good explanation for KBO orbits, there has also been intense criticism of the study. Now, Brown and Batygin are back with a new analysis that aims to address some of those complaints. Chiefly, other scientists noted that it's difficult to observe KBOs, so many searches focus on the more convenient regions of the sky. Thus, we could simply be looking a biased data.
The Planet Nine duo kept some of the original KBOs in the new data set, but it also includes new space rocks. They also discarded any object that appeared to be influenced by Neptune's gravity. The updated set of 11 KBOs still shows an unusual orbital distribution. The study claims there is just a 0.4 percent chance that these orbits are a coincidence. A greater than 99 percent chance that there is a massive object affecting KBOs sounds high, but it's actually lower than the chance assigned to Planet Nine in the original 2016 study. You could argue, of course, that this is a much more realistic number.
Based on the new simulations, Batygin has created a "treasure map" of sorts that points the way to Planet Nine's most likely orbital arc. That expansive area crosses the luminous plane of the Milky Way, which might have helped Planet Nine hide from previous searches. This includes a chance in the expected orbit, bringing Planet Nine in closer to Earth. The original analysis estimated it has an orbital period of 18,500 Earth years, but now it's believed to be in the neighborhood of 7,400 Earth years. The pair believe we are only a few years away from spotting Planet Nine, and it may be the upcoming Vera Rubin Observatory in Chile.
The Planet Nine duo kept some of the original KBOs in the new data set, but it also includes new space rocks. They also discarded any object that appeared to be influenced by Neptune's gravity. The updated set of 11 KBOs still shows an unusual orbital distribution. The study claims there is just a 0.4 percent chance that these orbits are a coincidence. A greater than 99 percent chance that there is a massive object affecting KBOs sounds high, but it's actually lower than the chance assigned to Planet Nine in the original 2016 study. You could argue, of course, that this is a much more realistic number.
Based on the new simulations, Batygin has created a "treasure map" of sorts that points the way to Planet Nine's most likely orbital arc. That expansive area crosses the luminous plane of the Milky Way, which might have helped Planet Nine hide from previous searches. This includes a chance in the expected orbit, bringing Planet Nine in closer to Earth. The original analysis estimated it has an orbital period of 18,500 Earth years, but now it's believed to be in the neighborhood of 7,400 Earth years. The pair believe we are only a few years away from spotting Planet Nine, and it may be the upcoming Vera Rubin Observatory in Chile.
It cant be a normal gas giant (Score:2)
Re:It cant be a normal gas giant (Score:5, Informative)
Most Kuiper Belt objects discovered so far are between 35 and 70 AU, less than a fifth of the proposed distance to Planet Nine. And astronomers still discover them mainly when the Milky Way does not cross the Ecliptic, which introduces a large selection bias into the KBO class.
Re:It cant be a normal gas giant (Score:5, Interesting)
For example, Jupiter emits a fair bit of infra-red [uoregon.edu], thanks in large part to the heat generated by it's sheer mass. Our system's two gas giants do this as a function of their composition. If there were another gas giant in the Kuiper belt, then it should in theory be emitting quite the IR signature. In fact, there's even a chance that Hubble would have spotted it with NICMOS [esahubble.org].
Re:It cant be a normal gas giant (Score:5, Informative)
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Re: It cant be a normal gas giant (Score:2)
Probably, because AFAIK, 'Ice Giant' is a relatively recent classification. It took years for the general public to get used to Pluto not being a 'planet', and THAT was in the news & controversial. I'd guess that 98% of adults older than ~30 probably have no idea that it's an 'ice giant' (vs 'gas giant'), or that there's even such a thing AS an 'ice giant'.
I mean, hell, I remember once finding a children's book about space travel at my grandmother's house that belonged to my Baby-Boomer uncle. It was pu
Re:It cant be a normal gas giant (Score:5, Informative)
If you put a copy of Jupiter at distance d, then it would have a visual magnitude of about
m /Log[10]
~= Mag_Jupiter + 10*Log[ d/ 4 AU]
~= -2 + 10*Log[ d/4 AU]/ 2.303
(I am assuming that the amount of light approximately varies inversely with the 4th power of distance.)
At d = 400 AU, then
m ~= 18
which is bright enough that I think it would have been found by now. (I'm guessing that we have found and tracked all 18th magnitude stars. Maybe this if false for stars in the Milky Way area of the sky.)
On the other hand, if you put a copy of Neptune at 400 AU, I think that it would have a visual magnitude of
m /Log[10]
~= Mag_Neptune + 10*Log[ d/ 30 AU]
~= 8 + 11 = 19.
(I am not an astronomer, so there might be an error in these rough calculations.)
ytene suggested that it may be even easier to detect in the infrared.
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Please forgive the ignorant follow-on question, but since the outer planets all have very different appearances - I guess thanks to significant differences in the composition of their atmospheres - could this suggest that a KBO of gas giant size *might* have yet another variation on atmospheric composition?
If that's a possibility, then what's the least light-reflective atmosphere we can think of... and what would the reflectivity of that be within the orbital ranges suggested? It just se
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Nice.
A couple of things.
Given the mass range in the paper, we're talking more super-earth than ice giant. The smaller size alone could easily add another magnitude.
The paper's most probable magnitude is 21.
Eris was discovered in 2005. Its magnitude is 18.7. 20+ is _hard_, especially if you don't known where to look.
Re: It cant be a normal gas giant (Score:2)
This might be a situation where an occultation of a star might be needed to detect it.
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The bottleneck is not spotting it, but rather recognizing it. At those magnitudes, lots of stars will also visible such that it wouldn't stand out. A time-lapse comparison is needed so as to spot it moving between frames. That's how Pluto and Arrokoth were discovered.
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And the time-lapse trick is much harder with this planet. Pluto averages 39 AU from the Sun. Planet 9 is hypothesized to be 380 AU out, nearly 10 times the distance. That gives it an orbital period of around 7400 years. So, if we had a cand
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My rough calculation is that you'd have to wait only about 2 months to move beyond the resolution error of a typical high-exposure photo.
Earth's parallax movement perhaps can also be tapped.
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I think the point is that it big enough to be a planet, but very far away, so it is very dark. There are telescopes that can see very dim objects, and there are zillions of such objects within our field of view. The problem is, to pick out this one very dim object, so we know it is not a distant galaxy or whatever. Planetary motion maybe? Stars and galaxies don't do that. Just guessing.
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an ancient, but otherwise totally useless endeavor.
It's how you know when to plant crops. Among other things.
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It's how you know when to plant crops.
So judging by genital shrinkage due to coldness, how much fresh food you have had access to in the past 6 months, or the amount of liquid and frozen precipitation over a recent period can't be used either?
If the genitals aren't out, neither are the seeds for planting. This is the onanism way to spread seed on the ground.
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Now, about those other things. Perhaps you could provide a list?
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Now, about those other things. Perhaps you could provide a list?
Probably not for you. You wouldn't understand, you're too dense.
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"...you're too dense." I guess by that you mean he's not a gas giant?
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No, not really. There is an Intergalactic Cosmic Council that decides these things. Astronomers brought the issue in front of the council and their verdict was: we don't give flying rat's ass about your arbitrary designations about what is or what is not a planet; just make up your damn mind and be done with.
Astronomers: Okay, Pluto is not a planet.
IPC: Very good, now go pester some other council, we're busy investigating why Sagittarius A is behaving in an unseemly fashion.
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Re Sagittarius A, isn't that why Pierson's Puppeteers are heading toward the Magellanic Clouds?
Re:Just give us more money and we will find it (Score:5, Informative)
etc.pp.
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At first thought I would have fully endorsed this notion. But I got to thinking. Genital size notwithstanding, there are certainly purely terrestrial cues as to when to plant what, and in fact, these cues (e.g. fuzz on the tree buds, appearance of insects) may be actually better for agricultural production in terms of planting times, as they will be more sensitive to non-solar variables that effect plant growth cycles (such as climatological conditions, pollinator migrations).
Similarly, there are other ways
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Well, a lot of agriculture was dependent on rivers flooding, when the rains came and such rather then winter vs spring. The Egyptians for example were quite happy to be able to predict the Niles flooding by keeping track of Sirius.
Where I am, the original inhabitants gardened oysters, clams and such and watching the Moon to infer tides was likely helpful. For farming here, knowing when the last frost happens would also be useful and going by when certain plants blush their buds for example may be lagging so
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"the young men would go to Hawaii... a thousand mile canoe trip." Wait a minute. The length of the islands from Ni'ihau to Hawai'i (the Big Island) is under 1000 miles, I think, and you seldom if ever lose site of land going from one island to another, even between Kaui and Oahu (just over 100 miles apart), and given the height of the mountains on both, I would think you could see one or the other from 50 miles away. And if not, you could often see the cloud banks over one or the other.
As for watching th
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So where are you???
British Columbia. It's a ways from Hawaii and you definitely will be out of sight of land for most of the journey.
When creating and maintaining clam (and oyster?) gardens, knowing when the lowest tides happen helps. One of many links, https://www.cbc.ca/news/canada... [www.cbc.ca]
Re:Just give us more money and we will find it (Score:4)
It is amazing how some people can make a living from looking at the sky - an ancient, but otherwise totally useless endeavor.
Your phone is looking at satellites in the sky all the time.
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Na I turned off GPS so they can't track me. No wonder they are trying so hard now to get a vaccine chip in me...
And you took out the sim card?
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It is amazing how some people can make a living from looking at the sky - an ancient, but otherwise totally useless endeavor.
Your phone is looking at satellites in the sky all the time.
I'm sure the GP spends his entire time using his phone to watch anti-science Youtube videos, so his phone looking at the sky is also a totally useless endeavor. ;-)
Re: Just give us more money and we will find it (Score:1)
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This mud ball, on the other hand, is where visual art, music, poetry and such are as well as all your friends and relatives. It is far more important than the stars.
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I'd love to know how studying how planets and stars form and evolve is useless. Without it, we'd have no theory of relativity, so no GPS. We'd have no theory of gravity. We'd have no remote sensing. We'd have no global telecommunications system. Ok, weather forecasting is pretty useless, but we'd have no weather tracking. We'd have no clocks. We'd have no calendar. We'd have no aircraft navigation systems. We'd have very little nuclear physics and it'd mostly be wrong.
All this from looking at the stars.
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Ok, weather forecasting is pretty useless, but we'd have no weather tracking.
I don't really know how much we can credit weather forecasting improvements on this type of stuff, but in general weather forecasting has improved dramatically since the 1970s, and measurably since the 2000s. Increased weather forecasting accuracy has saved big bucks in all sorts of fields.
It would be very surprising if there wasn't (Score:5, Informative)
These disks are a hundred to several hundred AU in radius, and given the seemingly outright *favorable* conditions for planet formation in the outer regions - well below the snow line temperature, long shearing timescale, and likely too little ionization to drive the magnetorotational instability - it is hard to believe that we would not see objects form at these radii. Thus unless objects that form at a very large radius spiral in a long ways, or the outer regions are not favorable to formation before the star ignites and literally blows the disk away, it would be surprising if there isn't at least one gas ball lurking out there.
Then again, the observed existence of hot jupiters clearly indicates that yes, an enormous degree of inspiral (presumably clear up to destruction) does routinely occur.
Planet formation dynamics are an incredibly complex and fascinating subject.
Pluto (Score:5, Funny)
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Yeah, we had a perfect Planet IX until they voted it off the island.
Now the same people are demanding a new one.
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Well yeah, just because we don't serve dwarfs here doesn't mean we don't like other people.
Honestly all meetings from the IAU should start with "I'm not a planetist but..."
I thought everyone knew this... (Score:1)
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Pluto
Dave
Alvin
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Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Persephone
CaÃna
Antenora
Ptolemea
(Judecca)
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I prefer "Mickey and Goofy" over "Dave and Alvin". (What have chipmunks got to do with this?)
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You forgot Antichthon / Counter-Earth / Mondas / Gor.
(here is an excellent resource on this subject [wikipedia.org])
Don't they mean Planet 10? (Score:3, Insightful)
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Yes. Pluto is a planet.
We/they are looking for Planet X.
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It even has its own Wiki page
https://en.wikipedia.org/wiki/The_Tenth_Planet/ [wikipedia.org]
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Our Solar System already has 9 discovered planets.
Only for those who never managed to master that old Sesame Street game "One of These Things Is Not Like the Others".
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Except we know Pluto is less like any KBO and any dwarf planet than it is any of the major planets.
So if we're playing "not like the others", you lost.
Re:Don't they mean Planet 10? (Score:4, Interesting)
Pluto is a tiny ball of ice almost exactly the same size and origin as other balls of ice in the Kuiper Belt, and is physically unlike any of the eight planets.
Pluto's orbit is highly elliptical, like many Kuiper Belt objects, and unlike any of the eight planets.
Can you name even one attribute that would actually make Pluto more similar to the eight planets than to its hundreds of cohorts in the Kuiper Belt?
"Was discovered by a plucky and dedicated astronomer!" doesn't count.
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I managed three real intrinsic properties of Pluto. It wasn't hard.
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The orbit is not a property of the object and virtually all exoplanets including superjupiters have highly eccentric orbits. You don't consider those dwarves as well, do you? No? Then the orbit is worthess.
Qualities of Pluto:
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Except we know Pluto is less like any KBO and any dwarf planet than it is any of the major planets.
Just because a Chinese person doesn't have black skin, doesn't make them a Caucasian. There's a reason they adopted another specific definition to help classify Pluto.
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No there isn't. They wanted to avoid having to do more work in schools. That was the line given at the time and I see no reason to disbelieve them. No planetary scientist agrees with the IAU decision and planetary scientists are in fact scientists. Astronomy is listed amongst the humanities.
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No planetary scientist agrees with the IAU decision
That's like saying no climate scientist agrees with the IPCC. Sorry but your comment is horseshit. But not just any horseshit. Like real horseshit, like not true horseshit fallacy kind of horseshit.
No there isn't.
And yet despite your assertion that "a line was given at the time", what was actually given was long reasoned arguments as to why Pluto differs from both all other planets as well as KBOs, and is precisely why they came up with another definition.
Be a bit less anti science. Climate change is a thing. COVID isn't
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Except we know hundreds of superjupiters around other stars that also haven't cleared their orbit. Defining a superjupiter as a dwarf planet seems kinda stupid.
We also know that eccentric orbits are the rule amongst exoplanets, which shows Pluto's orbit isn't remotely unusual for super Earths and super Jupiters.
More importantly, though, that is extrinsic. It isn't a property of the object, but of its environment. In absolutely no field of endeavour do we classify objects like this. An oak does not become a
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> has 9 discovered planets.
Had. Past tense. One of those buggers got reclassified as dwarf planet as it could not clear its own orbit and had some large sidekick dangling next to it.
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Except we've seen hundreds of exoplanets, some superjupiters, that also haven't cleared their own orbit. Besides which, that's neither intrinsic, not is it invariant by definition. When devising ontologies, it's important to choose things that actually relate to the object under consideration. It's also important to choose an ontology by merit and not by a very tiny self-selected bunch of people who openly stated it was to avoid doing work with their kids for school.
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We'll undoubtedly be changing our ontology when (or if) we learn enough about other solar systems that we can tell whether ours is in any way typical.
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We've looked at hundreds, if not thousands, of other solar systems. Ours is very much a rarity amongst the set we have seen. Even if other systems turn up that look like ours, that's an awfully large class of solar systems to ignore.
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No. It has either 8 or (at least) dozens, depending on which definition you use.
- spherical, in orbit around the Sun and clears its orbit: 8
- spherical and in orbit around the Sun: lots
There's no definition based on physics that includes Pluto and excludes Ceres and other minor planets.
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Really, this whole business about whether Pluto is a planet or not is absurd. The word "planet" is just that--a word. Nothing important comes from calling Pluto a planet, or not.
Otoh, Pluto is too small (and maybe in the wrong place) to have had the gravitational effects attributed (rightly or wrongly) to Planet X. So again--calling Pluto a planet (or not) does absolutely nothing to clear up the alleged problems with these other bodies' orbits and axis tilts.
Why does it matter? (Score:4, Funny)
Neil DeGrasse Tyson would just find a way to deprecate it and not call it a planet.
Pluto-assassinating bitch.
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They've already got that in the rules. It clearly wouldn't have "cleared its orbit". (Of course, neither has Jupiter, see the Trojan asteroids, but it's in the rule.)
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They've already got that in the rules. It clearly wouldn't have "cleared its orbit". (Of course, neither has Jupiter, see the Trojan asteroids, but it's in the rule.)
The rule should probably be revised to 'cleared or controlled its orbit." Jupiter pins the Trojan asteroids in place. Those are the Jupiter-Sun L4 and L5 Lagrange points, islands of gravitational stability. Any rock that wanders in at a low enough velocity can't get out again. All of the planets have trapped at least a few things in their Sun L4 and L5 points, including Earth. Earth has a Trojan asteroid too, catalog number 2010 TK7. The "cleared its orbit" criteria comes with an asterisk "with the ex
Re: Today's Internet is a joke. (Score:1)
Once this was the tenth planet... (Score:2)
Once this was the tenth planet, which had the intriguing enigmatic name "Planet X."
Until, but then Pluto got plutoed as the ninth planet.
Still an intriguing possibility. I wish either NASA, ESA, or perhaps the private space firms would send a probe to the other side of the Sun, collect data, and then the probe would return with the data.
So if there is a "hidden" planet opposite the known planets it could be detected. Easier said than done, such a mission requires out of line of sight for communication, and
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Not to mention that plenty of probes are already in non-geocentric orbits.
You mean heliocentric vice geocentric - Sun vice earth centered orbits.
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I wish either NASA, ESA, or perhaps the private space firms would send a probe to the other side of the Sun, collect data, and then the probe would return with the data.
So if there is a "hidden" planet opposite the known planets it could be detected.
So...uhm...not exactly sure what you're expecting to find there. Planets move, and all of the planets move at different paces. There is a whole lot of time when we are on the opposite side of the sun as other planets. Uranus and Neptune are particularly prone to this, but you won't be able to see Mars during part of October, either.
The only way for this to be useful is if there's a planet that is precisely synchronized to Earth's orbit and thus always invisible...also managing to not-appear on any of the do
Re: Once this was the tenth planet... (Score:2)
We visit the other side of the sun for quite literally half of every year.
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As others have mentioned, you appear to have forgotten that everything not at Earth's distance from the sun travels around the sun at a different speed than Earth, thus bringing those objects to "our" side of the sun very frequently.
Also, a parallel Earth that is directly opposite us relative to the sun would be detectable via the effects caused by its gravity.
But you're also wrong on this part:
Easier said than done, such a mission requires out of line of sight for communication, and once deployed the probe would have to be self-correcting, navigating.
Problems with communication would only happen if the satellite was exactly opposite Earth. You don't have to do t
Bear in mind (Score:2)
Only a tiny minority of the IAU call Pluto a dwarf planet. Most planetary scientists and a significant number of astronomers regard Pluto the same as they always have.
As for Planet X, it's almost certainly not a gas giant that far out. If we look at other systems, you don't see many where there's huge planets on the outer edge. They tend to have very eccentric orbits and cut in very close to their sun. Our own solar system featured that behaviour until Saturn formed, which pulled Jupiter into its current or
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Your reasoning doesn't work. As planets get farther from their sun, they become more difficult to detect, so there's no reason to expect that we would have detected distant planets around either our sun or any other. And if you've got a huge aphelion, there's no reason to expect a small perihelion, even with a very eccentric orbit. And they'll spend most of their time at the more distant parts of their orbit.
That said, a gas giant does seem unlikely. But if it were there, it would be likely to not have
Tenth. (Score:2)
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"Pluto is a planet": so what? or so what if it isn't? It went millennia without anyone knowing it was even there, so how does the category we assign it to change *anything*?
Everything crosses the galactic plane. (Score:2)
Doesn't every orbit around our sun cross the plane of the Milky Way?
Although something slow moving and hiding the the denser parts could be a reason we haven't noticed it.
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The planets orbit the sun at about a 60 degree angle from the galactic plane, so they cross the plane regularly.
But there's nothing that requires a Kuiper Belt object to orbit in the same plane as the planets. See: Pluto.
This one could be in an orbit such that it's always in or very close to the galactic plane.
Solved by Alf (Score:1)
I though Alf wrapped this up decades ago with Dave and Alvin?