Thursday, January 21, 2016

Super Earth May Exist, but It's NOT "Planet Nine"


The potential discovery of a Super Earth in the outer solar system made huge headlines today. Inferred from the eccentric orbits of several tiny objects in the Kuiper Belt, this planet is estimated to orbit 19 billion miles or 200 astronomical units (AU) from the Sun, with one AU equal to the Earth-Sun distance of approximately 93 million miles.

This distant world, which would take between 10,000 and 20,000 years to orbit the Sun, is estimated to have a mass ten times that of the Earth.

Significantly, this planet has not been observed or actually detected. Its existence is inferred solely through computer simulations.

Unfortunately, one of the two scientists conducting the study, Mike Brown, who has spent a decade obsessed with the very unprofessional claim that he “killed” planet Pluto, decided to take a page from the presidential candidates and use this possible discovery to promote his own personal agenda.

He did this by naming the potential object “Planet Nine,” a deliberate affront to those who reject the IAU planet definition just one day after the tenth anniversary of New Horizons’ launch.

By using this name on a press release distributed to countless media outlets, Brown assured that his version of the solar system would be repeated again and again in article headlines as the only view of the solar system.

It is a view based on the highly emotional, unscientific premise that our solar system cannot have “too many planets,” so artificial lines have to be drawn to keep the number of planets small.

By referring to any new planet discovered as “Planet Nine,” he is inherently denying the existence of the ongoing debate over planet definition and over the number of planets our solar system has.

According to the geophysical planet definition, held by many planetary scientists, a planet is any non-self-luminous celestial spheroidal body orbiting a star, free floating in space, or even orbiting another planet. If an object is not a star itself and is large enough and massive enough to be rounded by its own gravity, it is a planet.

That means, as I have often stated before, that dwarf planets are planets too. Alan Stern, the person who coined the term “dwarf planet” intended it to refer to a third class of planets in addition to terrestrials and jovians.

According to this definition, there is no requirement that an object “clear its orbit” to be considered a planet.

So for the many scientists and members of the public who adhere to the geophysical planet definition, our solar system has a minimum of 13 planets, 14 if we count Charon as part of a binary system with Pluto. In order from the Sun, these are Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Charon, Haumea, Makemake, and Eris.

Inner Oort Cloud Object Sedna and the recent, distant discovery known as 2012 VP113 and nicknamed “Biden,” are likely spherical as well, raising that count to 16. As Alan Stern noted, “If they do find it (this proposed object), it’ll be more like Number 19, not Number 9.”

Unfortunately, very few media outlets chose to seek the geophysical point of view. Instead, most simply more repeated the nonsense that Brown is “the Pluto Killer” and quoted only him and his research partner, Konstantin Batygin.

And Brown made sure to get in as many digs at Pluto and at denying the existence of the ongoing planet debate as possible, making statements such as, “There have only been two true planets discovered since ancient times, and this would be the third.”

Over and over, he presented his opinion as fact, and few journalists even thought to question it. From the geophysical view, more than two planets have been discovered since ancient times because Ceres, Pluto, Haumea, Makemake, and Eris are true planets too.

Brown and Batygin supposedly considered other names for this possible new object, including George, Planet of the Apes, Jehoshaphat and Phattie. Any one of these would have been better than “Planet Nine,” which is not really a name but a statement saying his view of the solar system is the only view.

Most following the New Horizons mission now know just how much of a planet Pluto is. It is more geologically active than Mars and has features such as flowing ice and likely cryovolcanoes, which strongly suggest an internal heat source no one anticipated.

There is complex interaction between its atmosphere and surface, and there may even be an underground ocean that could harbor microbial life. A good number of New Horizons scientists have commented that given these features, there isn’t anything else they can call this world other than a planet.

None of this apparently makes any difference to Brown, but then again, he doesn’t study Pluto. So insistent is he on the controversial “requirement” of orbit clearing that he states of the potential discovery, “The fact that it could affect the orbits of other objects over such a wide area would make it “the most planet-y of the planets in the whole solar system.”

Why should an object’s effect on other objects make it more “planet-y” than its intrinsic properties?

Theories positing the existence of a large planet far beyond Pluto have been around for a long time. Announcing that a computer simulation points to this possibility is an ideal opportunity to excite the public about space exploration and what might be out there.

Instead, Brown effectively hijacked this story to promote himself, his imagined accomplishment of having “killed” Pluto, and his subjective view of our solar system, conveniently ignoring that his view is just one in an ongoing debate.

The first principle of propaganda is, “A lie repeated a thousand times becomes the truth.” Another is “He/she who defines the terms wins the debate.”

Brown may repeatedly attempt to pass off his view of the solar system as the only view, but that does not mean the media or the public has to accept it. The story of a possible new solar system planet can stand on its own, without endless promotions of Brown and his book, parts of which stray so far from astronomy to the point that he actually devotes an entire chapter to engagement rings!

If I read a book about the solar system, the only rings I want to learn about are those around planets or asteroids. I suspect many other astronomy enthusiasts share that view.

One of the view journalists who did go out of his way to be fair and balanced in this story is Alan Boyle, author of the book The Case for Pluto. His article can be found at .

In that article, Alan Stern discusses what an actual discovery of a large outer solar system planet would mean from the geophysical point of view. He says, “And if it is found, it’ll confirm lots of work predicting the Oort Cloud is littered with planets, and the solar system made dozens to hundreds of them.”

Anyone who rejects the IAU planet definition or even just wants to acknowledge that planet definition is an ongoing debate should simply refuse to call this object “Planet Nine,” especially if it is actually found. Do not give Brown the power he seeks to define the terms and thereby win the debate.

This object would in no way replace Pluto, and its discovery has nothing to do with Pluto; it would simply be a fascinating addition to our solar system, which has room for many planets. That in itself makes for a fascinating story.




Smarter than the average Bear said...

The mark of a good scientist is having an open enquiring mind, Brown doesn't!

DarkCyborg said...

Agreed. Buuuuuut...

Satellite Planets are planets too. Don't forget then! We have more than 30 know planets in our solar system.

By the way, Titan is my favorite (and my number for it is #7.1, because it orbits the planet #7 and is the largest satellite planet around it - Pluto is #11, by the way).

And I'm Brazilian, sorry for my English :x

Anonymous said...

I think this new planet should be called "Cirno" referencing both Brown's insistence that it's the ninth planet, and Brown arrogance. But, that would probably be an insult to Cirno.

Neil Bates said...

Thanks, Laurel. Here is yet another reason to restore Pluto as a planet: we can refer to "Planet X" with the convenient double-entendre that it is unknown, and also "the tenth" planet rather than the true ninth. And historically, a hypothetical planet beyond Pluto has been called "Planet X" for similar reasons.

Steve Kuchinsky said...

Excellent article Laurel! But about the 13 planets, wouldn't the moon be #14?

Laurel Kornfeld said...

@Steve Thank you! In this case, I'm counting primary planets, which orbit the Sun directly. Spherical moons, in my opinion and that of many planetary scientists, should be considered secondary or satellite planets. Earth's moon would fall into this category.

Neil Bates said...

Ahhh ... Well I see that the issue really isn't necessarily about restoring the Solar System to "nine" planets, since if Pluto is included we might want to say there are even more — not even counting "Planet X" if it's found. Still, maybe we should not rely only on arbitrary size etc. considerations, but use some discretion involving distance, complexity of system, etc. It's not like there is a vivid natural dividing line, anyway.

StevoR said...

Spot on and well said.

Dmh Frou said...

Great article Laurel, I posted a link on Pinterest to it at

and I'm following your boards on Pluto there too.
I have a question, as an astronomer have you ever heard about the hypothesis of a brown dwarf orbiting the Sun, as a companion similar to the Gliese system? If yes, what do you think about this hypothesis, could the "Super Earth" be this brown dwarf?
I'm asking as a layperson, I'm not an astronomer, I've read about this in other blogs.
You have a beautiful blog here, congrats! :-)