Makingsimulatedstellarobjectslearnthestepsofourcosmictangois a start, butthere's nosubstituteforcoldhardevidence.
And I meanthatliterallyiftherereallyis a rockyplanetoutpastNeptune, thatthingisgoingtobeverycoldandhardandastronomersneedtofindit, whichiseasiersaidthandoneobjectswayoutthatfar.