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A 1980s space telescope may have seen planet nine
- d_graeme 5y agoCool. So in ten years time, they'll tell us again that it was actually a 'gas giant' not a 9th planet
- croddin 5y agoIf this object did exist, wouldn't it be classified as a dwarf planet since, like Pluto, with a highly elliptical orbit it would be difficult to clear it of other Kuiper belt objects?
- alex_young 5y agoAn object with multiple Earth masses could hardly be classified as a dwarf planet.
- kbelder 5y ago"A "dwarf planet" is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite." According the the wrong-headed AIU definition. So, yes, _Jupiter_ could be a dwarf planet, if it hasn't cleared it's orbital neighborhood for some reason.
- robocat 5y agohttps://en.wikipedia.org/wiki/Clearing_the_neighbourhood https://en.wikipedia.org/wiki/Clearing_the_neighbourhood Weird definition since it prevents deciding if an exoplanet is a planet or a dwarf planet. It smells like a compromise proxy measure for: orbital stability, in a reasonably circular orbit, plus rule out Pluto. Maybe there is some deep reason for using that measure, but it is not obvious.
- bnralt 5y agoAs far as I can tell, many planetary scientists aren't particularly fond of the definition either. I believe the initial plan that the IAU had after the discovery of Eris was to classify dwarf planets as planets, but some of the members didn't like the idea that our solar system would suddenly get a lot more planets, so pushed for the current awkward and ill-defined IAU definition. Though there are a lot of people that present the IAU definition as if it were simply the will of "science," if you look at the 2006 debate about it amongst scientists, it was actually fairly contentious.
- vikingerik 5y agoIt very well could. Defining a planet as major or dwarf goes by its ability or inability to "clear the neighborhood", to control or remove objects of smaller mass in its orbital area. 225 AU is a long way, and the volume of space to clear goes up quadratically with distance; this object would have 50,000 times more space to clear than does Earth. The orbital period also goes up with distance [edit, reply is right that it's the 3/2th power], so so does the time between interactions with any particular object. Multiply those together and you would have an object more than cubically (3.5th power) less effective than Earth at clearing its neighborhood over time, such that it may not have happened in the lifetime of the solar system.
- lanna 5y ago> The orbital period also goes up quadratically with distance By Kepler's Third Law, isn't it proportional to the square root of the cube (3/2th power) of the distance?
- ithinkso 5y agoIt's on a plane. Circumference goes up lineary
- vikingerik 5y agoIt's undefined whether "clearing the neighborhood" involves the spheroid at that distance or just the plane. It hasn't come up, since all eight known major planets do satisfy the three-dimensional criterion. We'd probably revise or clarify the definition if we discovered an object that cleared its plane but not its volume.
- dylan604 5y ago>ability or inability to "clear the neighborhood", who said it has finished the job? has the correct paper work be filed? according to the permits in the galactic construction offices, the work is not scheduled for completion for a few hundred more millennia.
- skykooler 5y agoI think the criteria are more along the lines of "gravitationally dominate its orbit", which due to the perturbations of KBOs this object would do. Otherwise, basically all planets would be demoted (e.g. Neptune has not cleared its orbit because Pluto is there, Jupiter hasn't because of the Trojans, etc.)
- readthenotes1 5y ago"Scientists who search for Planet Nine estimate that its mass is several times bigger than Earth’s... " So no. It won't be a dwarf planet.
- slyall 5y agoI asked Mike Brown this on twitter earlier this year and he said it will have cleared out it's orbit so that won't be a problem. " definitely clears! " https://twitter.com/plutokiller/status/1433802812945625095 https://twitter.com/plutokiller/status/1433802812945625095
- odyssey7 5y agoThe sufficient-but-not-necessary conditions for identifying a planet are called into question as a workable definition once more. We’ve duck-typed the solar system, I guess.
- SkittyDog 5y agoI hate to be the one to break the bad news to you, but... That's pretty much how all science works. https://en.m.wikipedia.org/wiki/Species_concept https://en.m.wikipedia.org/wiki/Species_concept Categorization is a leaky abstraction. Use them when they're useful, and ignore them when they become more trouble than they're worth.
- odyssey7 5y agoAt risk of maybe going too far on a tangent, I understand this idea and the species example is a good one. The planets are different because they were first defined as mystical and cultural concepts, before they could be understood as scientific ones. There are plenty of people who still think about the planets as cultural concepts rather than scientific ones. (What is a Jupiter? It’s a thing in space that our culture has named “Jupiter.”) I think we should define the planets the way co-star does. By listing them: DATA PLANET = MERCURY | MARS | ETC Scientists can have their own definitions of things, but they will face resistance if they try to dictate culture through their definitions. https://www.costarastrology.com/why-haskell/ https://www.costarastrology.com/why-haskell/
- SkittyDog 5y agoI'm pretty sure animal and plant species also existed as cultural and mystical concepts, long before science was a thing. All of your analysis can be applied equally well to species, as well as planets... Or the four seasons (winter, spring, summer, autumn) or the five Oceans, or the seven Continents. They're all simply human attempts to impose neat category boundaries across a continuum of natural phenomena that are definitely not neat. Categories can be useful, but they often lead to pointless arguments by lay people (a la Pluto's relegation) when we start to fetishize a human-created category structure as an essential expression of underlying reality. It's just plain old human narcissism.
- mgaunard 5y agoThere's always something weird beyond Uranus.
- kordlessagain 5y agoIf whomever was responsible for demoting Pluto from being planet nine is reading this, you’re a dweeb.
- __MatrixMan__ 5y agoI'm not that guy, but I took a semester of astrophysics so I'm practically an expert. If you drop the "has cleared its orbit of most obstacles" criterion, you have to admit something like 105 new planets. Pluto will always have a special place in our hearts, but it had to be done.
- gammarator 5y agoThat’s Mike Brown! His book “How I Killed Pluto and Why It Had It Coming” is a great scientific memoir, and very funny too. https://www.penguinrandomhouse.com/books/19851/how-i-killed-pluto-and-why-it-had-it-coming-by-mike-brown/ https://www.penguinrandomhouse.com/books/19851/how-i-killed-...
- kristopolous 5y agoI've got a silly question, could there be some long term effects of an object that had been there? For instance, could there be some kind of elasticity or residue, something like radiation that could cause a dissipated gravitational like effect long after the thing has moved on or otherwise "disappeared" in some way? In this very likely wrong model maybe the thing causing the effect visited hundreds of years ago and was just passing through and so it's no longer directly observable...
- worewood 5y agoThat subtitle was in no way accidental.
- starwind 5y agoRelevant part: For the recent work, [Michael] Rowan-Robinson redid his search from nearly 40 years ago and found three points in the data from late summer 1983 that indicate some object moving across the sky. The data sources sit low on the galactic plane, though, meaning that the satellite was taking the data through plenty of dusty, cloudy material that can emit infrared light. In other words, the work is something of a long shot. And Rowan-Robinson is well aware of that. “Given the poor quality of the IRAS detections, at the very limit of the survey, and in a very difficult part of the sky for far infrared detections, the probability of the candidate being real is not overwhelming,” he wrote in his paper.
- _Microft 5y agoIsn’t that bigger news than it sounds at first? Part of the problem of finding planet nine must be knowing where it currently is on its orbit. A few possible observations should help to narrow down the space in which to look for it by a lot (rather: would make it almost clear where it currently is). Maybe JWST could be of help with testing the hypothesis that these early infrared observations of a moving object were of planet nine - once it has finally and savely launched and begun its operations?
- xook 5y agoWould have commented this same thing. It should be a matter of translating the coordinates into a search pattern to look at with JWST.
- samus 5y agoEvery millisecond on JWST is booked years in advance already. Unless Planet 9 searchers turn up with some good guesses and not just a search pattern, other research with far more likelyhood of success has priority.
- AareyBaba 5y agoFinding it may be complicated if it is hiding behind a cloaking device.
- tectonic 5y agoMike Brown recently wrote a summary of his and Konstantin Batygin's paper 'The orbit of Planet Nine'. By looking at Kuiper belt objects (KBOs) whose orbits appear skewed by the invisible gravity of a possible Planet Nine, accounting for observation bias, and running a ton of simulations and MCMC, they concluded: if it exists, Planet Nine has a mass of 6.2 (+2.2/-1.3) Earth masses and a perihelion (closest approach to the Sun) of 300 (+85/-60) AU. The median distance at aphelion is around 500 AU. Those are not small error bars, but they do constrain the search, and this proposed finding of 225±15 AU and a mass of 3-5 ME could just ~barely~ fit. The summary: https://findplanetnine.blogspot.com/2021/08/the-orbit-of-planet-nine.html https://findplanetnine.blogspot.com/2021/08/the-orbit-of-pla... We’ve been covering this search in Orbital Index (https://orbitalindex.com https://orbitalindex.com), subscribe if you want updates.
- tectonic 5y agoAlso, Mike Brown's free 'The Science of the Solar System' course on Coursera is excellent. Highly recommended. https://www.coursera.org/learn/solar-system https://www.coursera.org/learn/solar-system
- neunz 5y agoExcellent suggestion!
- zionic 5y agoI’m just mad we’re losing out on “Planet X”. When I was a kid Pluto was a planet so the new one was X (10) and it was cool. Now this new planet is just going to be planet 9 again… totally lame.
- api 5y agoIf they don't name it Yuggoth I will be disappointed. https://lovecraft.fandom.com/wiki/Yuggoth https://lovecraft.fandom.com/wiki/Yuggoth
- Hemospectrum 5y agoThere’s all kinds of silly names they could borrow from stories hypothesizing its existence. Nemesis, Nibiru, Vulcan, and Planet X, just for starters. But in all likelihood it will end up as something much more anodyne.
- BitwiseFool 5y agoI think the IAU will only accept names from Mythology.
- pndy 5y agoHere you go: https://www.iau.org/public/themes/naming/ https://www.iau.org/public/themes/naming/ - in short, it can't just be named by snapping fingers obviously as there's a review and approval process. They extended naming conventions to other cultures already - IIRC Roman and Greek sources were "drying off"
- gs17 5y agoThere's a region on Pluto provisionally named after Cthulhu, citing Lovecraft as "an underworld mythology". If the IAU accepts the name, it would make this possible too.
- deleted 5y ago[deleted]
- yongjik 5y agoSure, I'm OK with naming it Le Creuset. Oh, you meant anodyne ....
- gre 5y agoHere's a youtube video by Anton Petrov describing the paper https://www.youtube.com/watch?v=ZSyAO4fGZOE https://www.youtube.com/watch?v=ZSyAO4fGZOE
- ziddoap 5y agoHe's always quick on these, and always with quality videos. Anyone with an interest in space who has not watched any of Anton's videos are seriously missing out.
- Diederich 5y agoSo say we all. I watch all of his videos and it's always an interesting, learning experience.
- rand0mx1 5y agoHis videos are unnecessarily long
- sounds 5y agoThe most vital information is presented and explained in the first 30 seconds of the video.
- go_elmo 5y agoThats me! thanks for the input. Yt really puts you in a bubble unfortunately. Would be cool if one could "explore" different branches of it...
- HenryKissinger 5y agoIf Planet 9 contains rare earth metals, mining and manufacturing facilities could be built there. This should help alleviate the chip shortage.
- deleted 5y ago[deleted]
- echelon 5y agoWe have plenty of rare earths here on our homeworld. If we run out (which we won't), we'll scavenge before we build the trillions of dollars of infrastructure necessary to mine the solar system.
- guerrilla 5y agoRare Earth metals aren't actually that rare. We even have a lot of big mines that are closed right now because its not profitable enough yet and many other sites enrirely undeveloped.
- kjs3 5y agoOr we could, you know, build mining and manufacturing facilities on a planet that's, say a couple of AU away, instead of a couple of hundred AU. There's reasons we've done neither.
- gameswithgo 5y agoIs this performance art? Do some napkin math on the quantities of fuel alone required to do this.
- pfdietz 5y agoRare earths are neither particularly rare, nor particularly likely to be unusually abundant on a Planet 9. However! A Mars or Earth-sized planet sufficiently far out in the solar system might be sufficiently cool to be able to retain helium in its atmosphere, without being a gas giant planet. If so, it might conceivably be the best place in the solar system to obtain 3He, an isotope that has considerable attractiveness for use in fusion reactors. A D-3He fusion rocket might even provide a nice way of getting out there and back in a reasonable time.
- smlacy 5y agoAm I the only one who's mildly annoyed by the 9th planet being referred to as Planet X? Seems like "Planet Ix" (same pronunciation!) would have been a better name?
- rich_sasha 5y agoI think it's a semi-deliberate pun. It was Planet 10 when people started looking for it. Then it would be "Planet 9", which is confusing. So they called it then "Planet X" as in 'ex', nerdily harking back to the good old days when Pluto was still a planet.
- lainga 5y agoThe designation was not a Roman numeral but Lowell's designation for "unknown". It would have been the 9th planet if discovered, at the time Lowell coined it, anyway
- deleted 5y ago[deleted]
- cheaprentalyeti 5y agoI just bent space from Ix. Many new machines there.
- kjs3 5y agoThe theory was proposed and it was anointed 'Planet X' when Pluto was the 9th planet, with X as the Roman numeral for 10. Now it's a play on 'X' being something unknown. Nothing to get annoyed about.
- nashashmi 5y agoHonest question: Can’t the oddity of planet orbits also be explained by a sun in motion causing the orbits to be a little dragged shape? The direction of drag is probably the ghost planet 9?
- Majromax 5y agoDragged through what? It's not like the interstellar medium has friction. In addition, our entire solar system condensed out of the same primordial soup, with the same sort of motion about the galaxy. Just as our sun is in motion about the galaxy, the planets are in essentially the same motion.
- fsckboy 5y agoyou're asking a good question, that I'm not really qualified to answer, but in short I think no, that's not the explanation. what you're talking about is a general relativistic phenomenon: just as it takes a few minutes for the sun's light to reach earth, it takes an equal amount of time for the sun's gravity to get here, and by then the sun has moved on. However, I don't think that is responsible for these orbits.
- lutorm 5y agoLol, Hubble is a "1980s space telescope". It was launched in April 1990....
- lp0_on_fire 5y agoAmazing how they could design and built such a device in four months... /s
- lutorm 5y agoI don't think you read my comment correctly...
- excalibur 5y agoThe article is referring to the Infrared Astronomical Satellite. https://en.wikipedia.org/wiki/IRAS https://en.wikipedia.org/wiki/IRAS
- lutorm 5y agoI know, my point is that "80s space telescope" doesn't mean it's something super old that's not in use today...
- WarOnPrivacy 5y agoThe Vera Rubin Observatory in Chile is under construction and will image the entire sky every week using the largest digital camera ever built. Hopefully searches along the plane of the ecliptic won't be sabotaged by Starlink or other LEO satellites.
- tick_tock_tick 5y agoLarge facilities were never threatened by Starlink as they easily compensate the issue was amateur's and very small facilities.
- spacemark 5y agoNot true at all, totally depends on the type of observation campaign. Plenty of big observatory projects are negatively impacted by the eternal march of "progress."
- tick_tock_tick 5y ago> "progress." Do you really think Starlink is not a step forward? It is realistically the only path to get the whole world access to the internet.
- SllX 5y agoIf by “whole world” you mean the wilderness, then sure! Otherwise we’ve had no issues laying cables to any place people live, so long as it makes sense to do so.
- WarOnPrivacy 5y agoIf by "makes sense" you mean to ISP shareholders - for ISPs to take federal USF funds and never, ever deliver on the required upgrades or expansions (eg:Frontier@WV,Verizon@PA), due to regulatory capture.
- marcodiego 5y agoPlanet nine... why not simply consider it as something in the same level of conspiracy theories until better evidence arrives?
- twirlock 5y agoThere is evidence, but what you mean is "evidence," i.e. "headlines," i.e. "I am being assured by multiple sources that my worldview is still socially acceptable." So to answer your question, you shouldn't.
- tiahura 5y agoCan anyone explain how we’re able to detect dozens of exoplanets (Wiki says we’re up to 4864!), but not be able to detect every large boulder around our own star?
- netcraft 5y agoThere are two main ways we detect exoplanets. The primary way that I believe accounts for the vast majority of planets we have detected is the transit method. Basically we watch the light from a star very closely and look for a dip in the amount of light coming from it as a planet transits in between us and the star. This of course depends on the planet to pass directly between us and the star, and that means that its ecliptic plane has to be directly edge on with us. The second method is that we are able to detect minor wobbles in a star that infers that there is a planet sized object that is perturbing the star. I believe this is only able to detect Jupiter sized objects up to brown dwarves or other stars though, and even that depends on the distance to the star, and I believe only when the planet orbits at a relatively close distance (I believe closer than the kuiper belt) The problem in both cases as it relates to planet 9 is that you arent detecting the planet as much as its effects. If you take any planet that far away from a star and youre trying to detect either the very little bit of light that it might be reflecting or its infrared heat signature if youre lucky, but both are incredibly dim.
- widforss 5y agoIf that is the threshold for discovering exoplanets, haven't we already found Planet Nine since we definetly have detected the planet's effects?
- raxxorrax 5y agoGood objection actually. We could say that we found exoplanets visually, can determine its mass and size and therefore its density and make careful prediction about its characteristics from that, which is probably nothing more than an educated guess. Here we just found its gravitational effect.
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- cosmojg 5y agoI really hope it's a bowling-ball-sized black hole so we can start slingshotting rockets off into deep space.
- xvector 5y agoOr build a Dyson-sphere like machine around to capture its energy and power humanity for ages
- dotancohen 5y agoRadius of bowling ball: 12 cm [1] Mass of black hole with radius 10cm: 0.00004062 Sun Mass [2] 0.00004062 Sun Mass in kilograms: 8.124E+25 [3] That's significantly more than 10 times the mass of the Earth. Even a grape-sized black hole would be more massive than Earth. Highly unlikely to be such a massive object, hithertofore undetected. The most massive object expected would be smaller than the Moon, which for a black hole would be the size of a human ovum. [1] https://hypertextbook.com/facts/2009/MarwaElfar.shtml [2] https://www.omnicalculator.com/physics/schwarzschild-radius [3] https://www.unitconverters.net/weight-and-mass/sun-s-mass-to-kilogram.htm
- f1refly 5y agoI only lovecraft where here to witness this and possibly write even more stories about yuggoth and the eldritch things that might lurk on it
- 02020202 5y agoAnd when Sitchin was translating the old sumerian texts no one believed in anunnaki. Yet here we are.
- akban 5y agoI grew up being told there were 9 planets, then I started being told there were actually 8 planets, now I'm being told again that there are really 9 planets. Wish the astronomers would just make up their minds.