Wide-Field Infrared Survey Explorer finds no evidence of phantom planet hiding in the solar system


March 10, 2014

Planet X is a hypothetical star or planet, theorized to be responsible for Earth's mass extinction events 
(Image: Shutterstock)

Planet X is a hypothetical star or planet, theorized to be responsible for Earth's mass extinction events (Image: Shutterstock)

Image Gallery (4 images)

A study of data captured by NASA's Wide-Field Infrared Survey Explorer (WISE) satellite has disproved the existence of the hypothesized large celestial body, dubbed "Planet X." The planet or companion star was, some believed, responsible for the periodic mass extinctions that have taken place in Earth's past.

NASA's WISE satellite was designed to image the entire sky with infrared light, to aid the answering of fundamental questions on the origins of celestial bodies ranging from planets to galaxies.

Before being placed in hibernation and subsequently woken in 2013 to form the NEOWISE mission, the WISE mission operated from 2010 to early 2011. During this time it carried out two full surveys of the sky, imaging nearly 750 million stars and galaxies and creating a catalog that scientists could turn to in order to examine questions and theories such as that posed by the hypothetical Planet X.

WISE imaged 750 million stars and galaxies over its lifetime, including this stunning picture of the Andromeda galaxy (Image: NASA/JPL-Caltech/UCLA)

Scientists and conspiracy theorists alike originally hypothesized the existence of a planet or small star in the outer solar system. This is due to the seemingly regular timing of mass extinctions that had taken place on Earth due to asteroid impact such as the one that wiped out the dinosaurs in the Cretaceous period.

The leading theory on Planet X was that a phantom planet or small star lying somewhere beyond Pluto would periodically re-enter the inner solar system, moving through bands of comets as it did so. The gravity of Planet X would then deflect these comets towards Earth, causing the mass extinctions found in geological surveys.

A nearby star shines red against a backdrop of its distant cousins (Image: DSS/NASA/JPL-Caltech)

However, whilst WISE searched the entire sky and discovered hundreds of millions of stars and asteroids, the existence of Planet X was not supported by the extensive infrared survey. No object that exceeded the size of Saturn was discovered to a distance of 10,000 astronomical units (au), with one au being the equivalent of 93 million miles. WISE also detected no planet or star larger than Jupiter as far as 26,000 au. With earth being one au from the Sun and Pluto 40 au from its parent star, this data ostensibly disproves the existence of a hitherto undetected planet at the fringes of the solar system.

Whilst WISE found no evidence of Planet X, it did find an abundance of celestial bodies closer to our solar system than any previously discovered. The second study by WISE revealed 3,525 stars and brown dwarfs within 500 light-years of our Sun, the closest of which, a pair of brown dwarfs just 6.5 light-years away, represents the closest system discovered in almost a century.

This pair of brown dwarfs represent the closest system to our star discovered in almost a century (Image: NASA/JPL/Gemini)

Ned Wright of the University of California, Los Angeles, and principal investigator of the mission stated that "Neighboring star systems that have been hiding in plain sight just jump out in the WISE data."

Scientists were able to determine the relative proximity of stars discovered by the WISE survey by observing how much the star moves in relation to those around it. Stars that are closer to us appear to move faster against the backdrop of their more distant cousins.

Source: NASA

About the Author
Anthony Wood Anthony is a recent law school graduate who also has a degree in Ancient History, for some reason or another. Residing in the UK, Anthony has had a passion about anything space orientated from a young age and finds it baffling that we have yet to colonize the moon. When not writing he can be found watching American football and growing out his magnificent beard. All articles by Anthony Wood

It's NASA. Protocol requires that data to go to the U.S. Govement before the public. If they did find anrogue planet in our solar system, we wouldn't be told anything about it.

Jesse Jones

First of all, NASA is a civilian agency. Second, NASA has thousands of employees in dozens of centers and research facilities across the country and the data was not just reviewed by NASA employees but also universities. The project leader of WISE is Dr. Edward L. Wright of the University of California, Los Angeles. If there really was a PlanetX, it would be sensational news that would be impossible to keep a secret. As we know from recent events, it is impossible to keep anything a secret these days.


Well that is a relief. Will sleep more easily and my beard will grow better. Less stress you know.

Oh, I bet there are lots of secrets out there, but PlanetX would have been a hard one to keep.

What is a tad disturbing are the number of "Drive Bys" from objects that would mess up someone's day. Thirty foot long boulders with a picture of Earth painted on them, to office building sized objects, just zipping on by, winking & waving at us, and all we can do is say, "Shazam!" Pathetic. Von Braun had us on Mars by 1985 or so and I bet that kind of effort would have allowed us more than just wincing up like a 95 pound weakling, hoping to not get smacked. Time to go to the gym.

Post a Comment

Login with your Gizmag account:

Related Articles
Looking for something? Search our articles