Astronomers have looked back at potential place where the elusive , hypothetical Planet Nine could be hiding , if it exists at all , once again narrow down where to look .
Looking for planets in orbit around other stars is a relatively easy labor , in comparison to hunting for Planet Nine , also known asPlanet X. basically , when a planet break past a asterisk we are note , we see a dip in light . Thousands of exoplanets have been happen upon in recent years around other star topology using thistransit method acting .
From our linear perspective , only Venus and Mercury transit our host star , construct this method useless for finding satellite ( andother object ) in our own Solar System , and these two were visible to the naked oculus anyway . Saturn , Jupiter , and Mars were also found using the " looking up and seeing a shiny aim " method .
Uranus was found likewise in 1781 by uranologist William Herschel , after he noticed a bright objecthad movedcompared to other stars in the survey , and took a snug expression . But Neptune was discover by astronomer and mathematician Urbain Le Verrier in 1846 after he noticed there was a difference between the observed cranial orbit of Uranus and the way Newtonian physics predicted its orbit to be . Le Verrier proposed that the difference could be explain by another major planet beyond Uranus , and made predictions as to the arena of this previously unknown eubstance . Looking in that localisation , German astronomer Johann Gottfried Galle found the planet Neptune .
The rationality why people are looking for a mysterious ninth planet at all is because in 2015 two astronomers from Caltech presented evidence that six object past the cranial orbit of Neptune were bundle together in a path that suggested they were being " herd " by something with a large gravitational pull . Now , the same squad has narrowed down where they believe the object – which they say istwo to four timesthe radius of Earth – is . Still , it continue tough , with suggestions that it could even be just astatistical anomalyand extract bias on behalf of the stargazer from Caltech .
In a fresh pre - print paper submitted to The Astronomical Journal , the team has used data from the Pan - STARRS1 survey to eliminate 78 pct of the potential places that had been key out by previous research as places to look for the hypothetical satellite . While this may vocalise disappointing – find a new planet would be great news to all but the most diehard of Pluto fans – it does mean they have narrowed down where to take care , if there is a planet to be get .
Areas of finical interestingness include near the galactic plane , some of which will be covered by the upcomingVera Rubin Observatory view . Nevertheless , the team face at reasons why the planet has not yet been ground .
" An obvious possibility , of course of action , is that Planet Nine does not exist , " the team wrote in their paper . " Such an explanation would need new explanation for multiple phenomenon take note in the out Solar System . Until such explanations are available , we stay on to regard Planet Nine as the most likely hypothesis . "
Another alternative is that Planet Nine is further out and more massive than previously remember , make it more difficult to spot . For now , the team believes that such a major planet best explains the orbits of take note objects in the outer Solar System .
" The clump of the directions of the electron orbit is the best love , but there is also the large perihelion distance of many target , the existence of highly inclined and even retrograde objects , and the high abundance of very outlandish electron orbit which cross inside the orbit of Neptune , " wind author Dr Micheal Brown toldUniverse Today . " None of these should happen in the Solar System , but all are easy explainable as an core of Planet Nine . ”
The study is usable on the pre - print serverarXiv .
