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Where is Planet 9?Updated a year ago

😆 Well, if it exists, wouldn't we (and NASA and astronomers worldwide) love to know! It's almost incredible to think that a planet 5 to 10 times the size of our Earth might be sitting right in our own solar system, which makes it tempting to believe that it doesn't exist and some of the alternate theories are true, but until the question is resolved, the search continues!

Wikipedia does a decent job of describing the current status of that search: "As of September 2019, no observation of Planet Nine had been announced. While sky surveys such as Wide-field Infrared Survey Explorer (WISE) and Pan-STARRS did not detect Planet Nine, they have not ruled out the existence of a Neptune-diameter object in the outer Solar System.The ability of these past sky surveys to detect Planet Nine were dependent on its location and characteristics. Further surveys of the remaining regions are ongoing using NEOWISE and the 8-meter Subaru Telescope. Unless Planet Nine is observed, its existence is purely conjectural. Several alternative theories have been proposed to explain the observed clustering of TNOs."

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