Name: New Evidence Suggests Planet 9 Is Real–The Kuiper Cliff Mystery Explained
Uploaded: 2026-08-10T16:21:52.000Z
Description: It’s a mystery that has captivated star watchers for nearly 125 years.

Codex Legendarium explores the world's greatest mysteries through the lens of science, history, mythology, and human curiosity. From cosmic anomalies and ancient civilizations to forgotten technologies and unexplained phenomena, each episode uncovers extraordinary stories that challenge what we think we know about our universe and our past.

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A giant planet could be lurking in the outer reaches of our solar system, hiding in the shadows just out of view of our telescopes. But maybe not for much longer.

It’s a mystery that has captivated star watchers for nearly 125 years. The famed Planet X—or Planet 9—depending on who you ask.

Generations have searched for it, intrigued by peculiar planetary orbits in deep space that shouldn’t be happening unless something big is out there, stirring up trouble. The hunt has uncovered an entirely different planet, and a zone so strange in the outer reaches of our solar system that crossing it is like falling off a cliff.

Is Planet X real? Why is the history of an unconfirmed space giant tied to the rejected 9th planet, Pluto? Why is there a ring around our solar system that’s virtually devoid of celestial bodies? And what if there is something out there, but it isn’t a planet?

Now, a brand new, cutting-edge telescope might just be able to find out.

In this episode, enter the Codex Legendarium for a closer look at:
<ul>
 	<li>Planet X vs. Planet 9,</li>
 	<li>The Kuiper Belt,</li>
 	<li>The mystery of the Kuiper Cliff,</li>
 	<li>Pluto and its history,</li>
 	<li>Gerard Kuiper,</li>
 	<li>Neil Armstrong’s “crunchy snow”,</li>
 	<li>The unusual orbits of Sedna and other dwarf planets in deep space,</li>
 	<li>Trans-neptunian objects,</li>
 	<li>Gas giants,</li>
 	<li>Ice giants,</li>
 	<li>The assumed characteristics of Planet X,</li>
 	<li>The discovery of Pluto,</li>
 	<li>Percival Lowell,</li>
 	<li>The Lowell Observatory in Flagstaff, Arizona, and its 24-inch Clark refractor telescope,</li>
 	<li>Lowell’s “Memoir on a Trans-Neptunian Planet”,</li>
 	<li>Clyde Tombaugh,</li>
 	<li>What happened on Feb. 8 1930</li>
 	<li>Pluto almost becoming Minerva,</li>
 	<li>Astronomer James Christy,</li>
 	<li>Pluto’s moon Charon,</li>
 	<li>An Italian theory about canals on Mars,</li>
 	<li>How the Babylonians found the first 5 planets,</li>
 	<li>The symbolism and significance of the number 9,</li>
 	<li>NASA’s WISE mission,</li>
 	<li>Japan’s AKARI Satellite,</li>
 	<li>Backyard Worlds: Planet 9,</li>
 	<li>The Vera Rubin Observatory in Chile,</li>
 	<li>Black holes and death stars,</li>
 	<li>and above all: the search for a pinball in a cosmic arcade.</li>
</ul>

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New Evidence Suggests Planet 9 Is Real–The Kuiper Cliff Mystery Explained

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