Once , cartographersdrew dragonson the unknown bits of maps . Now , somepeopleliketo fill theouter solar systemwith an undiscovered planet or two , often hump as Planet X. The reasons vary – exact sighting , overrefinement in the sphere of other planet or traffic pattern to cometic observations . But does this idea have more nub than the ancient versions ? The answer depends on how large , and how remote a planet you ’re discussing .
What We bonk Is Out There
Only this year a newobject was announcedwith an domain that extends out to almost 70 billion kilometers from the sun . 2012 VP113 , nicknamedBiden , will credibly be just one of many .
Biden however , is hardly a giant object . At 450 km wide it is smaller than several asteroid belt residents . Ice is easy for sobriety to shape than John Rock , so if Biden is , as suspected , mostly ice , it will be separate as adwarf planeton the basis ofits shape , but it sets few imaginations aflame .
Sedna , the first objective detected at these distances is or so 1000 kilometer across , similar in size toCeres , the inner solar scheme ’s largest asteroid . Something larger than this may be lurking in the icy outskirt of the Sun ’s influence . However , people talk of Planet X not Dwarf Planet X. Could there be something out there that is at least the size of Mercury ?
While bigger object should be easier to find , that does n’t work if they are too saturnine . Sedna reflectsa third of the Christ Within it receivesand constituent compound maydarken the aerofoil of some kayoed solar system aim .
Moreover , we only found Senda and Biden because they are both unusually stuffy to us at the moment . Sedna ’s distance ranges from 76 Astronomical Units ( the distance of the Earth from the Sun ) to 937AU . It was found at 90AUs . Only a tiny portion of its 11,400 class orbit is expend this close or closer . Similarly Biden ’s orbit extends to 452AU from the sunlight , but it was detected at just 83AU . So planetoids of at least similar size of it could well be undetected , much further out in their orbits .
Scott S Sheppard / Carnegie Institution for Science . The eye socket of Sedna ( orange ) and Biden ( ruby-red ) with Neptune and the Kuiper Belt to scale .
Closer in , theKuiper Beltis a flavorless disk usually defined as extending from the orbit of Neptune ( 30AU ) to 50 AU . Where once Pluto was the sole known inhabitant of this region we have now addedHaumea , Makemakeand a thousand object too small to be classified even as dwarf planets .
Erisis the magnanimous known inhabitant of the “ scattered disk ” made up of former Kuiper Belt object that had their orbits changed byclose encounter with Neptune .
NASA
That ’s Not a major planet , This Might Be A satellite
The idea of Planet X is rather more lofty than these frozen worldlets , however . Neptune was light upon in 1846 thanks to anomalies in the range of Uranus that suggested the presence of a large object further outexerting gravitational influence . In turn Percival Lowell remark oddities in Neptune ’s travels he blamed on a yet further planet . Pluto turned upvery closeto Lowell ’s had prediction , and was at first hailed as justify him . Further observations revealed Pluto to be far too low to have the influence suggested .
The idea of a mysterious object large enough to be messing with Neptune ’s orbit refuse to die but has become a sort of Bigfoot or Loch Ness Monster , be more in the more imaginative persona of the web than match review journals .
However , while it is potential for amateurcryptozoologiststo seek strange footprints in removed locations , telescopes up to of detecting something this faint do n’t come cheap . While serious attempts have been madeto find the influence of such planets , for most astronomers the need for something to be tote the outer planets around vanished when Voyager 2 spacecraft show Neptune is slightly lighter than antecedently thought . The new massexplains Neptune ’s and Uranus ' orbits dead . Moreover , none of the spacecraft currently exiting the solar systemare detecting gravitative tugs from tumid unknown objects .
Nemesis / Shiva / Tyche
Other people show the tea leaves of cometic approach pattern to reason that something is perturbing their orbits .
While some comet are thought to come from theKuiper Belt , most uprise in theOort Cloud , a regionbeyond 2000AUfrom the sun that may pass out a hundred time that , out to the point where the Sun ’s gravitative influence no longer outweighs that of other sensation . While the number of comets be in this distance is thought to be Brobdingnagian , their orbits commonly keep them where we can not see .
Sometimes however , something interact with an Oort Cloud comet , transfer the compass so it comes plunging into the inner solar system . Occasionally , further interaction with a planet keep it trap here , becoming a regular visitant to our sky .
In 1984 , in the wake of grounds that a comet was responsible for theextinction of the dinosaur , the great unwashed started to notice patterns in thetiming of mass extinctions . Perhaps a major planet , orborderline star , was interpose with the Oort cloud every 26million years , sending a burst of comets into the inner solar system , enough of which strike Earth to pass over gazillion of specie from the fossil record . The extinction periodicityremains controversial , but endeavor tofind a causehave fail .
An updated version propose Tyche ( Nemesis ’s sisterin mythology ) , a satellite of 1 - 4x the muckle of Jupiter revolve within the Oort Cloud and accounting for many of the comet entering the inner solar organisation . However , observations of Tyche ’s supposed locationreveal nothingand most astronomers arehighly skeptical .
In scientific discipline , as in living , it is always backbreaking to prove non - existence , but so far the case for Planet X does n’t look good .
