Since 2016, astronomers worldwide have been on the hunt, but they're coming up empty-handed. We're talking about the elusive "ninth planet," which, according to the latest estimates, should weigh in at 5 to 10 times the mass of Earth.
Its highly eccentric orbit supposedly stretches from 400 to 800 astronomical units from the Sun.
Just to give you a comparison, Neptune, our farthest planet, hangs out at 30 astronomical units (you probably already know that one astronomical unit equals about 150 million kilometers).
Basically, we're looking for a massive “white elephant”, hearing its trumpets in the distance, but darn it, it refuses to show itself… despite all our theories and high-tech tools.
But hold on, there have been some recent developments, and the scientific community is growing more confident that we'll nab this mysterious "beast" soon. Let's dive into what's been happening lately!
Before we get into the nitty-gritty of this tangled tale, let's clear up a fundamental point: on what basis do astronomers dare to suggest the existence of a celestial body they've never laid eyes on?
Well, suggesting the existence of a planet without direct observation isn't exactly new in astronomy. You could say this kind of search began on March 13, 1781, when Sir William Herschel spotted Uranus through his telescope. Now, you might wonder what the big deal was, but here's the kicker: in the years that followed, Uranus' calculated positions in the sky didn't match up with its actual positions...
They kept diverging.