9th planet nine artist caltechFEA

Astronomers Uncover Evidence For A Hidden 9th Planet

The imagined view from "planet nine" back toward the sun. Astronomers think the huge, distant planet is likely gaseous, similar to Uranus and Neptune. Credit: Caltech/R. Hurt (IPAC)
The imagined view from Planet Nine looking back toward the sun. Astronomers think the huge, distant planet is gaseous, similar to the other giant planets in our solar system. Credit: Caltech/R. Hurt (IPAC)

Hey, there might really be another planet out there. A pretty big one, too. Caltech researchers have found evidence of a giant planet tracing a bizarre, highly elongated orbit in the outer solar system. The object, which the researchers have nicknamed Planet Nine, has a mass about 10 times that of Earth and orbits about 20 times farther from the sun on average than does Neptune or nearly 56 billion miles away. It tremendous distance means it would take between 10,000 and 20,000 years to make just one orbit around the sun.

Artist depiction of the distant Kuiper Belt, where a possible new planet may be hiding. Credit: NASA
Artist depiction of the distant Kuiper Belt, where a possible new planet may be hiding. Credit: NASA

There’s been all sorts of baloney online for the past several years about a planet named Niburu the Destroyer headed for a collision course with Earth. This putative planet is not Niburu, which was never real in the first place but more of a chimera created out of fear of the unknown. And just to be clear, no one has seen Planet Nine. Its existence is inferred through mathematical modeling and computer simulations based on the clustering of six remote asteroids in the Kuiper Belt, a vast repository of icy asteroids and comets beyond Neptune. Planetary scientists Konstantin Batygin and Mike Brown of the California Institute of Technology in Pasadena say there’s only a 0.007% chance or about 1 in 15,000 that the clustering could be a coincidence.

Orbits of six distant Kuiper Belt asteroids that are clustered together possibly due to the influence of a putative new planet nicknamed Planet Nine. Credit: Caltech/R. Hurt (IPAC)
Orbits of six distant Kuiper Belt asteroids that are clustered together possibly due to the influence of a putative new planet nicknamed Planet Nine. Credit: Caltech/R. Hurt (IPAC)

The astronomers’ work appeared in the January 20th edition of the Astronomical Journal.

“Although we were initially quite skeptical that this planet could exist, as we continued to investigate its orbit and what it would mean for the outer solar system, we become increasingly convinced that it is out there,” says Batygin. “For the first time in over 150 years, there is solid evidence that the solar system’s planetary census is incomplete.”

That’s exciting news though I wonder why such a large object wouldn’t have been seen glowing in infrared light (heat) by NASA’s Wide-Field Infrared Survey Explorer (WISE). Still, the data are compelling. All six objects follow elliptical orbits that point in the same direction in physical space.

“It’s almost like having six hands on a clock all moving at different rates, and when you happen to look up, they’re all in exactly the same place,” says Brown. The odds of having that happen are something like 1 in 100, he says. But on top of that, the orbits of the six objects are also all tilted in the same way—pointing about 30 degrees downward in the same direction relative to the plane of the eight known planets. The probability of that happening is about 0.007 percent. “Basically it shouldn’t happen randomly,” Brown says. “So we thought something else must be shaping these orbits.”

In this artist's visualization, the newly discovered planet-like object, dubbed "Sedna," is shown where it resides at the outer edges of the known solar system. The object is so far away that the Sun appears as an extremely bright star instead of the large, warm disc observed from Earth. All that is known about Sedna's appearance is that it has a reddish hue, almost as red and reflective as the planet Mars. Credit: NASA/JPL-Caltech/R. Hurt (SSC-Caltech)
In this artist’s visualization, the newly discovered planet-like object, dubbed “Sedna,” is shown where it resides at the outer edges of the known solar system. The object is so far away that the Sun appears as an extremely bright star instead of the large, warm disc observed from Earth. All that is known about Sedna’s appearance is that it has a reddish hue, almost as red and reflective as the planet Mars. It orbits the sun once every ~11,000 years and it’s about 16,000 miles (25,750 km) across. Credit: NASA/JPL-Caltech/R. Hurt (SSC-Caltech)

And that something’s mass (weight) can be estimated by how the bodies move in their similar-shaped orbits. The potential planet would also provide an explanation for the mysterious orbits that two of the six trace — Sedna, discovered by Brown in 2003 and 2012 VP113. Unlike standard-variety Kuiper Belt objects, which get gravitationally “kicked out” by Neptune and then return back to it, Sedna never gets very close to Neptune. The presence of Planet Nine in its proposed orbit would shepherd objects like Sedna, slowly pulling them away into an orbit less connected to Neptune.

How would such a big planet manage to migrate so far away from the rest of us? The four heavyweights of the solar system are the gas and ice giants Jupiter, Saturn, Uranus, and Neptune. Planet Nine could represent a fifth, and if it got too close to Jupiter or Saturn, could have been ejected into a distant, eccentric orbit.

Caltech professor Mike Brown and assistant professor Konstanin Batygin have been working together to investigate distant objects in our solar system for more than a year and a half. - See more at: https://www.caltech.edu/news/caltech-researchers-find-evidence-real-ninth-planet-49523#sthash.xd18Wyvk.dpuf
Caltech professor Mike Brown and assistant professor Konstanin Batygin have been working together to investigate distant objects in our solar system for more than a year and a half. Credit: Lance Hayashida/Courtesy of Caltech

Brown and other colleagues have begun searching the skies for Planet Nine. Only the planet’s rough orbit is known, not a location. If the planet happens to be close to its perihelion (closest point to the sun), Brown says, astronomers should be able to spot it in images captured by previous surveys. If it’s in the most distant part of its orbit, the world’s largest telescopes will be needed to see it. If, however, Planet Nine is now located anywhere in between, many telescopes have a shot at finding it.

While Brown would love to find it himself, he hopes the publication of the paper will fire up astronomers around the world to look for it. The more the merrier, and the more telescopes applied to the job, the better chance of finding Planet Nine.

“All those people who are mad that Pluto is no longer a planet can be thrilled to know that there is a real planet out there still to be found,” he says. “Now we can go and find this planet and make the solar system have nine planets once again.”

For more information, please see the Caltech new release.

17 Responses

  1. It’s really puzzling that WISE didn’t detect an object that it was specifically designed to find. The other odd thing is the simulation only makes sense if the object(s) is on very high inclination relative to the plane of the ecliptic (+/- 100 degrees). That would make it a retrograde orbit to boot. Maybe the object was seen by WISE and is hidden in the enormous amount of data it sent back to Earth but since Batygin & Brown have probably thought of that already, the JWST (James Webb Space Telescope) will have no problem at all detecting it (them?) once it is launched in late 2018.
    I still have the feeling that it’s possibly an early April fools joke from the CalTech crowd, already legendarily known for their elaborate pranks

  2. Ben

    This is amazing!! I REALLY hope that it’s real! If it is real, what do you think about Minerva, the Roman form of Athena? I’d that doesn’t fly Diana is the Roman Artemis Those are human names, which could make it a bit weird. My fingers are crossed. Clear Skies.

  3. RC

    Even if “planet nine” is found, would it be a planet? I thought an object needs to “clear it’s orbit” to be considered a planet. With an orbit that takes 10,000-20,000 years, it seems that it would be impossible for this object to ever clear it’s orbit!

    1. Elitist scientific types?
      We shouldn’t generalize and condemn a vulnerable visible minority. Maybe Bob is part of that secretive conspirators group but I always thought I just fell in with the bad pocket protector crowd hanging out in the 500 & 600 section of my high school library 😉

      1. astrobob

        BC and Brian,
        The debate on Pluto will go on and on. If I had to pick sides though, I’d go with it as an asteroid. One of thousands or tens of thousands in the Kuiper Belt.

  4. Darin

    I have to say it…. it’s Nibiru and/or Planet X. Whatever it is, if it’s real, it is bad news for the inner Solar System when it comes, maybe some of those ancient texts are more accurate than we give give credit for? From one conspirator to another… I love you AstroBob!

    1. astrobob

      Hi Darin,
      Not to worry. Even if we discover it, Planet Nine will remain where it is just like Jupiter and the gang.

  5. Giorgio Rizzarelli

    I definitely like it, since (as from Wikipedia) one of the names they’re using for it is George. Although I like more their work name, Fatty.

    1. caralex

      Some are suggesting IX. Though, of course, you know what’ll happen there – it’ll be pronounced ‘Icks’.

Comments are closed.