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Planet X


Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune… perhaps Pluto if you studied them before 2006, maybe including the Sun if you know the song.

We have always taken for granted the existence of 8 planets in our Solar System. They gave us the data and we simply memorized it. But what if I told you of the existence of a ninth planet, what if you needed to learn a new list, a list including Planet X.

It appears that every time, more and more, we are closer to discovering the ninth planet in the Solar System. This time isn’t about one of those small iced worlds beyond Pluto’s orbit (just like the one Carnegie Institution announced a year ago), but of an authentic giant of dimensions comparable to Neptune. If its existence is confirmed, it would directly enter the fancied planetary club that Earth is part of.

Planet X


Planet X, also named Nibiru, was theoretically discovered by the astronomer Percival Lowell in the year 1906. He described Planet 9 as a body in the ends of the exterior Solar System (more distant than Neptune or Uranus) and with a mass equivalent to 6.6 times the Earth. This hypothesis was a debated theme for over 15 years and it was said that, if confirmed, its existence would explain the orbit disturbances in the “iced giants” (Uranus and Neptune), that to a point were incomprehensible.

Although the theory was proven wrong (at that date), it was thanks to one of Lowell´s disciples, Clyde William Tombaugh, that Pluto was discovered. Tombaugh, who had spent years searching for Nibiru, came across an iced body beyond Uranus. However, while Lowell had calculated that Planet X would have a mass equivalent to 6.6 times the Earth´s. Pluto´s mass is smaller than the moon.

The topic was not recovered until 1999, when British astronomer, John Murray announced that he had discovered a new planet while he studied comets in the borders of the Solar System. According to Murray the new planet would rotate around the sun at a distance a thousand times farther than Pluto, Planet X would complete the Sun’s orbit in six million years. Nonetheless, his thesis couldn’t be demonstrated.

Although Murray didn’t have any evidence of his finding; in 2008, a Planet X orbitJapanese team at Kobe’s University announced that despite Murray’s wrong calculations, there really was an invisible planet for us (we could receive data but couldn’t reach, by any telescope, to see it) at a distance of 100 AU (Astronomic Units, 150 million kilometers), and a size of two thirds the Earth.

This theory proves of the existence of a Planet X but it leads us to think that we could be talking of an object in Kuiper‘s Belt.

At last in January 2016, a group at California’s Technological Institute, led by the astronomers Konstantin Batygin and Mike Brown, found strong evidence of the existence of a ninth planet with the size of Neptune and located in the Borders of our Solar System. It has been named, temporally, Planet 9.

Until this date, there has not been strict proof of its existence- we still cannot see it. According to Mike Brown, it would take 5 years (2021) to scan the possible location of such planet.

At the present, the planet responds by the name of Nibiru, Planet X and Planet 9:

-Planet X: Referring to X as unknown, the name reflects the unfamiliar identity of the planet.

-Nibiru: The origin of the name Nibiru has no other source than from the BabylonianBabilonians tablet civilization which,  named one of the constellations they could view as Nibiru. The name means “crossing place” (“place of transition”) and although in some identified texts the name refers to the planet Jupiter, on tablet 5 of the “Enuma Elish” it is associated to Polaris, a constellation that concurs with the Earth’s  rotation axe.

-Planet 9: named taking into account the already known planets of the Solar System.


Planet X is becoming more of a trending topic, not on the scientific point of view, but as an apocalyptic aspect. It is said, or at least foretold, that in a not very far future, Planet X, because of its colliding orbit, will encounter the Earth on its way and destroy the whole of it.

However these revelations have been predicted for over a century, qualifying it as a legend.

Planet X has been treated as a way to threaten people, found in science fiction,
fantasy and even music. For instance, there is the instrumental rock band Planet X, which was founded in 1999.

Discoveries to Come

As you have probably heard, while we are trying to ask ourselves about the existence of Planet X, there is an infinite number of planets ready to be discovered and studied- some even with the possibility of sustaining life as we know it. We might even encounter other planets while we keep on discovering new things about Planet X.

Edited by: Daryn Dever, Arselyne Chery, and Shreya Singireddy