Hear Ye, Hear Ye! Carolyn Porco and Scott Tremaine are Wrong about Pluto!

Pluto with Background Stars

In a Facebook announcement dated February 14, 2023, planetary scientist Carolyn Porco takes on the role of planetary town crier, stating, “Hear Ye, Hear Ye! Scott Tremaine, renowned celestial dynamicist & a founder (along w/ my thesis advisor Peter Goldreich) of the field of planetary rings, has written a textbook on The Dynamics of Planetary Systems. At my request of some time ago, he included in his book a discussion of the definition of a planet...And what did he find? Pluto is NOT a planet !! Reason has prevailed. Rejoice!

Porco is admittedly an accomplished scientist best known for her work on NASA’s Cassini mission to Saturn. But in this case, she is wrong.

Reason does NOT prevail when a person with an agenda specifically requests that a fellow scientist push that agenda in his book while refusing to acknowledge the ongoing debate and both sides in that debate.

Porco’s position on the planet definition issue is actually more extreme than that of the IAU. She opposes the use of the term dwarf planet because she claims Pluto and Ceres are both asteroids! She states in the comments, “Actually, I don't ever use, and won't, the name 'dwarf planet'. It's inconsistent. How can something be a dwarf member of a category it doesn't belong to?”

Regardless of their own position on this issue, most scientists acknowledge the ongoing debate between dynamicists and geophysicists over the question of defining a planet. Most show respect for the opposing position even if they don’t agree with it.

In my writings and public presentations, I always make the effort to present both views. While I am clear on the view I hold, I believe it would be a disservice to readers and/or audience members to pretend my view is the only one and that all others have been discredited when this is not the case. I would rather members of the public hear both sides of this issue and then make up their own minds than feed them my viewpoint alone.

Porco goes on in subsequent comments to denigrate the geophysical planet definition by claiming roundness means nothing, adding, that the term dwarf planet “actually has no information in it besides 'sort of roundish'. On the other hand, ‘Pluto is a large Kuiper Belt Object’ tells you composition, location, relative size, approximate level of solar illumination, etc. Far more useful.”

To her, there is apparently no difference between tiny, shapeless asteroids and KBOs and objects large enough and massive enough to be rounded by their own gravity, in spite of the fact that the latter have complex processes not seen on asteroids and in some cases, seen elsewhere in the solar system only on Earth and Mars.

Just calling Pluto a large Kuiper Belt Object tells us nothing about its structure, its geology, its atmosphere, the interaction between its atmosphere and surface, its many varied terrains, its cryovolcanoes, its likely subsurface ocean, and its interactions with companion Charon as the solar system’s only binary planet system.

Pluto actually has far more in common with some of the larger, spherical moons in the solar system, considered by many planetary scientists to be secondary or satellite planets, than it does with tiny, shapeless Kuiper Belt Objects like Arrokoth. Today, planets such as Ceres; Jupiter’s moons Europa, Callisto, and Ganymede; Saturn’s moons Enceladus and Titan; Neptune’s moon Triton, and Pluto are the solar system’s top contenders for hosting microbial life due to the growing evidence that they harbor subsurface oceans.

Porco insists that gravitational dominance alone determines what is a planet without ever addressing the fact that this dominance depends on location and can lead to the same object being considered a planet in one location and not a planet in another one. If Earth were in Pluto’s location, it would not gravitationally dominate or clear that orbit.

Furthermore, she states, “But Mercury, Venus, Earth and Mars dominate their orbital corridors. If they hadn't, you wouldn't see them, you'd see a cloud of debris.

Does Mercury actually dominate its orbit, or does the Sun clear out debris there? The answer is unclear. Furthermore, there is no cloud of debris around Pluto. If there were, New Horizons would have had no trouble finding a second and even a third flyby target. The reality is the Kuiper Belt is vast, and most KBOs are nowhere near Pluto but much further out and very scattered.

She goes on to say, “'Round' is a perfectly useless criterion. It doesn't work for those distant bodies for which we don't, and won't for a very long time to come, if at all, have shape information for. So it fails as a metric for categorization...I mention ‘spherical’ but merely because it’s a side effect of (or proxy for) planetary properties and processes I am interested in with categorization in mind. E.g: a degree of planetary differentiation.”

But another commenter points out that gravitational dominance is much more difficult to detect at great distances than is roundness, and that time and the technological advancements that go with it will eventually answer these questions for distant objects, both in our solar system and others.

Additionally, planetary differentiation is very much related to roundness, as she admits in the sentence I bolded above. Active geology begins happening when objects reach the threshold of being rounded by their own gravity. Categorizing Ceres and Pluto as asteroids is bad science because it blurs the distinction between complex objects shaped by their own gravity and tiny ones that are often little more than rubble piles, held together only by their chemical bonds.

One commenter even repeats the false claim that Mike Brown discovered dwarf planets larger than Pluto despite the fact that no such dwarf planets have been found. Eris was initially thought to be larger than Pluto, but in November 2010, a team of astronomers led by Bruno Sicardy observed it occult a star and found it to be marginally smaller than Pluto though slightly more massive.

The persistence of this misconception after more than a decade is an example of why the IAU definition has harmed science by widely spreading confusion and incorrect information.

Unfortunately, the tone of the discussion in the comments takes a turn for the worse when Porco resorts to personal attacks against New Horizons Principal Investigator Alan Stern and other supporters of the geophysical planet definition, demeaning them by calling them “Pluto fanatics.”

Here are some examples of her inappropriate personal attacks:

“The Pluto fanatics were desperate to get a Pluto mission, and it was deemed of vital importance to maintain Pluto as a planet, so they would have more justification. They were practicing politics, not science.”

This is blatantly false. New Horizons was already approved and had already launched when the IAU vote took place. Most New Horizons scientists view Pluto as a planet because they favor the geophysical definition over the dynamical one. It is a purely scientific disagreement.

As New Horizons planetary scientist Cathy Olkin noted, "I naturally refer to Pluto as a planet because that seems like the right moniker. It has an atmosphere; it has interesting geology; it orbits the sun; it has moons. 'Planet' just seems right to me."

Porco went on to comment, “Stern has admitted he wanted Pluto to be a planet because he was afraid New Horizons wouldn’t be chosen if it wasn’t. He DOES appeal to emotions. You want to compare our respective domains of expertise? Stern did a mission to Pluto. I ran an experiment and published papers that required knowledge on my part in atmospheric meteorology, the kinematics and dynamics of planetary rings including faint rings of tiny micron-sized particles, the geology, geophysics and geodesy of planetary satellites, the tidal interactions between planetary bodies, the geysering eruptions of Enceladus, and a lot more. So, a body like Pluto is NOT outside my field.”

Again, her first statement is false. And while Porco did accomplish everything she states, Stern has also published numerous papers on many of these same subjects and is the world’s leading Pluto scholar. And his advocacy and leadership of the New Horizons mission essentially unveiled Pluto to the entire world.

Porco should feel secure enough in her own accomplishments to not belittle another scientist who clearly made extensive contributions to planetary science just because he disagrees with her on planet definition.

In one remark, she responded to a commenter by saying, “You are clearly an ignoramus and should keep your mouth closed.”

She even goes as far as comparing opponents of the IAU definition to climate deniers!

Ad hominem, or personal attacks, are a sign that someone is losing the debate.

Significantly, Porco blocks me on Twitter, and I could not comment on her Facebook page because it only allows those she permits to comment.

But I will not keep my mouth closed. I will not be silenced, and neither will advocates of the geophysical planet definition.

If someone has to resort to censorship to force their view on the world and disallow any comments that disagree with their view, they are NOT causing reason to prevail. They are enforcing tyranny And that is anything but a reason to “rejoice.”

Planet Pluto Discovered 93 Years Ago Today, February 18, 1930

Pluto Discovery CartoonPluto Explored Stamp

On February 18, 1930, exactly 93 years ago today, 24-year-old Clyde Tombaugh discovered Planet Pluto while blinking between two photographic plates of the same part of the sky taken six days apart at the Lowell Observatory in Flagstaff, Arizona.

He found a tiny dot that moved against the background stars from one plate to the next and thus succeeded just over a year after arriving at Lowell Observatory to take up the search for a new outer solar system planet, begun many years earlier by observatory founder Percival Lowell.

Now close to 130 years old, the Lowell Observatory is today holding its annual “I Heart Pluto” celebration to commemorate the discovery. The 13-inch Lawrence Lowell telescope Tombaugh used to take the photographic plates, recently restored, still sits within its original dome and is viewed by visitors every day.

Discoveries are not always well understood at the time they are made. In Pluto’s case, the new planet was too small to be resolved into a disk, leading some scientists to speculate that it might be a moon of a not-yet discovered larger parent planet.

Eventually, telescopes became powerful enough to resolve Pluto into a disk, but even Hubble images taken during the 1990s were fuzzy. The real revelation of Pluto in all its glory happened in 2015, when the New Horizons spacecraft flew by that world, imaged its varied terrains, and returned data that is still being studied and analyzed today.

Tombaugh and his fellow astronomers in 1930 had no way of knowing that they had found the first of many small planets in what is now known as the solar system’s third zone. They certainly had no inkling that the newly discovered world was one of many solar system objects that has a subsurface ocean possibly capable of hosting microbial life.

With the recent renewed interest in UFOs, it is important to remember that as of today, we have not even determined whether any other place in our own solar system harbors life. What we have discovered is that small planets Pluto and Ceres, as well as various moons of the gas and ice giants, likely have oceans beneath their surfaces that could potentially host microbes. Among that growing list of worlds are Jupiter’s moons Europa, Ganymede, and Callisto; Saturn’s moons Enceladus, Titan, and possibly even Mimas; Neptune’s moon Triton, and possibly Pluto’s binary companion Charon.

Distant planets like Eris and Sedna could also potentially host such oceans, but we won’t know until we send probes to study them up close.

On February 18, 1930, Clyde Tombaugh had no way of knowing that he had not only unlocked a third zone of the solar system, but also discovered a new class of ocean worlds that could be the prime locations for life taking hold beyond the Earth.

While it is clear that any extraterrestrial life in our solar system is limited to microbes, finding evidence of such life on any world would be one of the most significant scientific discoveries in history, as it would confirm life got started on worlds other than Earth.

Tombaugh also could not have known that the world he discovered was not a dead rock, but a geologically active planet that appears to have an internal heat source. No one expected something like this so far from the Sun. Today, the discovery of Pluto’s complexity and activity raises the possibility that other, even more distant worlds, could also be active planets.

Our technology is not yet at the level of being able to discover Pluto-sized planets in other solar systems, but the ability to do so is likely just a matter of time. While his search was for a gas giant planet, Tombaugh discovered the first in a new subclass of planets, the dwarf or small planets, largely but not solely present in the outer solar system. It is reasonable to hypothesize that other solar systems could also have regions like this, with scattered small planets that might be hiding subsurface oceans.

Some in the astronomy community did not give Tombaugh sufficient credit for his discovery back in 1930. His name was not even mentioned in Lowell Observatory’s press release announcing the discovery. Some astronomers of the day even looked down on him because he was a 24-year-old with just a high school education, not an astronomy PhD.

Yet even here, Tombaugh set a new trend though it would not become a “thing” until many decades later. This trend is that of astronomical and planetary discoveries being made by ordinary citizens, amateur astronomers, and even kids, who don’t have PhDs, but are passionate about the universe. Internet and telescope technology have opened the discovery process to interested citizens around the world, who have discovered exoplanets, brown dwarfs, supernovae, etc.

In so many ways, Tombaugh was far ahead of his time. This is also true of his staunch support of Pluto’s planethood. Doubts about that began not in 2005 but in 1930, soon after its discovery. Yet Tombaugh never wavered in his position even though he did not live to see the New Horizons flyby. Today, we know that Pluto is actually part of a binary system with Charon, meaning it is not one but two planets! The system’s four smaller moons orbit not Pluto itself but the center of gravity between Pluto and Charon.

This is a day to celebrate Planet Pluto and its opening of new frontiers in solar system and planetary studies. I personally wish I could be at Lowell Observatory’s I Heart Pluto celebration and hope to to be there for the centennial in 2030.

This year’s celebration will conclude with two talks that will be livestreamed online. The first, “The Future of New Horizons,” will be presented by Alan Stern on Sunday, February 19, at 7 PM Mountain Standard Time, which is 9 PM Eastern time. The second, “New Horizons: NASA’s Mission to Pluto and the Kuiper Belt,” by New Horizons engineer and mission operations manager Alice Bowman, will be presented on Monday, February 20, at 7 PM Mountain time/9 pm Eastern time.

Happy Discovery Day, Planet Pluto!

I Heart Pluto Festival Returns to Lowell Observatory

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It is almost the 93rd anniversary of Pluto's discovery on February 18, 1930, and that can mean only one thing--Lowell Observatory's annual I Heart Pluto celebration is back! Find out more here! While celebrations on February 18 will be in person at Lowell Observatory, there will be two talks livestreamed online on YouTube, one on February 19 and the other on February 20, as follows:

Sunday, Feb. 19, 7 pm: The Future of New Horizons: An Interview with Dr. Alan Stern

Monday, Feb. 20, 7 pm: The Latest News from Pluto and Arrokoth, with Alice Bowman, Engineer/New Horizons Mission Operations Manager, Johns Hopkins University Applied Physics Laboratory

Winter Solstice 2022

Winter Solstice Sunset

We have once again reached that noteworthy milestone—in the Northern Hemisphere, it is the Winter Solstice, the shortest day and longest night, the turning point of the year when darkness stops advancing, and the Sun appears to stand still in the sky before reversing course.

It’s been quite a year for space exploration. The James Webb Space Telescope successfully launched just about a year ago in spite of endless delays and repeatedly going over budget. It performed flawlessly in unfurling its sunshield and mirror, reaching its Lagrange Point position, and returning stunning images that open a new era of exploration for astrophysics, planetary science, and cosmology.

Another long delayed project, our return to the Moon, also finally launched this year. Artemis I sent back beautiful close up photos of both Earth and Moon, reminiscent of the famous Apollo 8 image captured at this time of year back in 1968—a picture that had a profound impact on many and played a key role in launching the environmental movement.

While 2022 has certainly had its share of challenges, it brought to fruition projects some doubted would ever launch, revealing that late does not mean never and reminding us that if something really matters, giving up should never be an option.

People who have had the good fortune to travel to space note it brings a life-changing perspective. From there, no borders are visible, just one fragile planet, now home to 8 billion people and numerous other life forms.

We all, not just world leaders, need that change in perspective because the problems our home planet faces cannot be addressed by just one group of people or one country. The only way we have any hope to stabilize our climate, mitigate the worst effects of climate change, and clean up our air, land, and water, is to come together as one people on one planet.

Too often, people look at the year-end holidays in ways that divide us, at a time when, more than ever, we need to unite to preserve our planet’s habitability for future generations—so we can one day explore the solar system and eventually the stars.

This day, at its core, is about hope. It is about light and life, known by the Romans as the Birthday of the Unconquerable Sun. This makes it an ideal time to treasure the gift of our planet and affirm the amazing things we can accomplish when we come together for a common goal—like launching JWST and sending astronauts to the Moon.

If we can do those things, we can save our planet for future generations. May the year that starts with the return of the light inspire us all to come together and choose a future of light and life.

“We are the power in everyone
We are the dance of the Moon and Sun
We are the hope that cannot hide
We are the turning of the tide!”

Why Space.com Article is Wrong about Pluto's Planet Status

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Space.com is usually a very credible information site about all matters space and astronomy, which is why its October 23, 2022 article, “Why is Pluto Not a Planet?” is so disappointing in its blatant one-sidedness.

More than 16 years after the controversial IAU vote on a highly flawed planet definition, it is difficult to understand why this site would publish an article that is extremely selective in every one of the sources it uses as references. From the IAU web page to Mike Brown to Ethan Siegel, formerly of Forbes, to a Neil Tyson video, the article refers almost solely to supporters of the IAU definition and completely excludes the many essays and articles written from the opposing point of view.

The article is problematic starting with its title, which, instead of acknowledging the ongoing debate over planet definition and Pluto’s status, simply states the IAU view as fact. This misleading title essentially presents the IAU view as “the truth” rather than as one view in an ongoing debate, and this notion is repeatedly assumed in the article, in spite of very sparse references to dissenting views.

Yet, there is absolutely NO reason to give the IAU position privilege as somehow being the “official” one in use. It is simply one of several definitions currently used by planetary scientists.

We need to address the factual errors in this article. Like many writings on this subject over the last 16 years, the writers cite Ceres’s discovery as a planet and subsequent demotion to asteroid in the mid-19th century as an earlier example of what happened to Pluto. However, they fail to acknowledge the other, crucial part of Ceres’s history.

Because it is very small, Ceres could not be resolved into a disk by 19th century telescopes. At the time, it therefore made sense to demote it to one of many asteroids in the belt between Mars and Jupiter. However, since then, Ceres has been found to be spherical, meaning unlike nearly every asteroid in that belt, it is squeezed into a round or nearly round shape by its own gravity. Most asteroids are simply rubble piles shaped by chemical bonds. The threshold for an object being spherical, in a state known as hydrostatic equilibrium, is crucial because this is when objects begin to experience geology and the complex processes seen on rocky planets.

In 2015, NASA’s Dawn mission revealed Ceres to have these complex features, including cryo-volcanoes and a possible subsurface ocean that could potentially host microbial life. These findings indicate the 19th century demotion was in error and that Ceres is more like the larger rocky planets than almost all objects in the asteroid belt, with the exception of Vesta and Pallas, which appear to have once been spherical only to have had a large portion knocked off during impacts with other objects.

Many scientists argue this makes Vesta and Pallas deserve an intermediate category between asteroid and small or dwarf planet, such as protoplanet. In fact, some scientists on the Dawn mission refer to Vesta as the solar system’s “smallest terrestrial planet.”

While some, including the writers of this article, invoke Pluto’s eccentric orbit and 17-degree tilt to the ecliptic as reasons for demoting it from planethood, the fact is several exoplanet systems contain multiple giant planets all orbiting in different planes. At least two systems have giant planets that cross one another’s orbits. And the ecliptic, often wrongly depicted as the path of the Sun, is actually the plane of the Earth in its solar orbit. Requiring objects to orbit in the same plane as Earth is a violation of the Copernican principle, which essentially states that Earth is just another planet, not the center of anything. And if giant objects that cross the orbits of other giant planets in their systems are not planets, what then are they?

The next inaccuracy in the Space.com article is its attribution of Eris’s discovery solely to Mike Brown. While Brown often presents himself as Eris’s sole discoverer, the fact is, Eris was discovered by a team of three scientists, the other two being Chad Trujillo and David Rabinowitz. Significantly, both Trujillo and Rabinowitz reject the IAU planet definition. Rabinowitz even signed a petition with hundreds of planetary scientists back in 2006 in response to the IAU definition, saying they would not use it.

The reference to the late Brian Marsden is also problematic, as Marsden, who apparently had a long feud with the late Pluto discoverer Clyde Tombaugh, was obsessed for decades with demoting Pluto so it could be put under his auspices at the IAU Minor Planet Center. Like Brown, he is a scientist who appears to have had his own agenda from the start.

While the article does acknowledge that only 424 IAU members voted on the controversial planet definition in 2006, it fails to note that this vote was held in violation of IAU bylaws, which prohibit putting a resolution to the floor of a General Assembly without first vetting it by the proper IAU committee. It also fails to mention that these 424 people were largely not planetary scientists but other types of astronomers, that they represented only four percent of the IAU’s membership, that no electronic or absentee voting was permitted, that 91 of the 424 voted for dwarf planets to be classed as a subclass of planets, and that an equal number of professional planetary scientists signed the afore-mentioned petition rejecting the IAU definition within days of its adoption.

Additionally, the writers fail to mention that when initially coined by Alan Stern in 1991, the term “dwarf planet” was intended to designate an additional class of small planets, not to designate a class of non-planets. In its unauthorized vote, the IAU essentially misused the term “dwarf planet” based on the fiction that dwarf planets are fundamentally different compositionally than their larger counterparts, a position proved false by the findings of the Dawn and New Horizons missions.

Even Neil Tyson is on record saying he has no problem with dwarf planets being considered a subclass of full planets!

As the article writers note, New Horizons found Pluto to have active geology; diverse features including windswept dunes, varied terrains, a layered atmosphere, cryo-volcanism, interaction between atmosphere and surface, and a likely subsurface ocean. Some complex features discovered on Pluto exist elsewhere in the solar system only on Earth and Mars!



To make matters worse, the article never acknowledges the alternative geophysical planet definition, which is preferred by most planetary scientists, beyond a vague mention of a 2017 proposal that “defined a planet as a round object in space that’s smaller than a star.” This is a major disservice to the proposal, presented to the Lunar and Planetary Science Conference that year, which centers planet definition on an object’s intrinsic properties rather than on its location, which the IAU definition does.

Most problematic is the article’s inherent assumption that only the IAU has the ability or power to determine what a planet is. Conveyed throughout this article, that sentiment can be seen in the statement noting Alan Stern and David Grinspoon’s 2018 Washington Post article urging reconsideration of planet definition “have fallen on deaf ears so far, and it seems unlikely the IAU will revisit the controversy any time soon.”

If such pleas to the IAU fall on deaf ears, and the organization refuses to address new data returned by the Dawn and New Horizons missions, then it is time to consider other venues for this discussion. The notion of science being decided by any type of “authority” went out with Galileo’s discovery of Jupiter’s moons over 400 years ago. A science publication like Space.com should know better than to appeal to any “authority” regarding scientific matters.

Finally, the article falls back on attributing opposition to the IAU decision to emotion, as seen in its Mike Brown quote, “Nostalgia for Pluto is not a very good argument, but that’s basically all there is. Now, let’s get on with reality.”

This comment is not only demeaning; it is also blatantly false. Scientists, amateur astronomers, and members of the public oppose the IAU definition not because of nostalgia or emotion but because the geophysical definition, which classifies objects first and foremost by their intrinsic properties, simply makes more sense based on what we have discovered about these objects. Brown does not get to unilaterally end the debate and get the last word simply because he wants to do so.

There are so many scientists and publications that articulately present the other side of this debate. I urge Space.com to do a better job in presenting this fascinating controversy to give readers a comprehensive understanding of both positions, allowing them to decide for themselves where they stand.

The authors of this article are right on one thing: This debate will continue for the foreseeable future.

Sources in response to those presented in the Space.com article:

Note: I wrote the response to the IAU statement and to Siegel’s Forbes article and embrace my role in this debate on Twitter with the handle @plutosavior .

I have covered the New Horizons mission for the website Spaceflight Insider since 2014 though the opinion expressed here is solely my own and not necessarily that of the site or its editors.

“Responding to the IAU: Pluto and the Developing Landscape of the Solar System,” a point-by-point rebuttal to the IAU statement:
http://laurelsplutoblog.blogspot.com/2013/02/responding-to-iau-pluto-and-developing.html

“A Geophysical Planet Definition” presented to the 2017 Lunar and Planetary Sciences Conference:
https://www.hou.usra.edu/meetings/lpsc2017/eposter/1448.pdf

“Guest Blog: Revisiting the Definition of a Planet,” Response to Ethan Siegel’s 2018 Forbes article:
https://cs.astronomy.com/asy/b/astronomy/archive/2018/05/18/guest-blog-revisiting-the-definition-of-a-planet.aspx#.Wv8Nwq7VyxY.blogger

“An Organically Grown Planet Definition,” by Alan Stern and Kirby Runyon, https://astronomy.com/magazine/2018/05/an-organically-grown-planet-definition#.Wv3x0d97CCI.blogger

“Pluto A Planet? New Research from UCF Suggests Yes,” by Robert H. Wells: https://www.ucf.edu/news/pluto-planet-research/

The Case for Pluto: How A Little Planet Made a Big Difference, by Alan Boyle: https://www.amazon.com/Case-Pluto-Little-Planet-Difference/dp/0470505443

Pluto Resistance Day

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Sixteen years. As of today, that is how long it has been since the IAU attempted to end the planet definition debate once and for all but instead created more chaos and confusion on this topic for the media, educators, and the general population.

The spread of misinformation their decision caused unfortunately continues to this day.

In the last few years, some people have taken to designating August 24, the day of the IAU vote, as a “holiday” titled “Pluto Demoted Day.” Writer Aryan Sahu, in a very one-sided article published on the website Merazone, actually described this day as “fun” and listed ways to “celebrate” it without even acknowledging the ongoing controversy. Unfortunately, the usually informative astronomy site TimeandDate.com also lists this day as a “fun holiday.”

But it is not in any way a holiday or something to celebrate.

I instead choose to call it Pluto Resistance Day. It’s the day when all who recognize the flaws of the IAU definition come together and affirm our commitment to advocate for a better planet definition in the long term and educate the public about the ongoing debate in the meantime.

Although there are good children’s books on the solar system that present both sides of the controversy, others that ignore the pro-Pluto view continue to be published. I cringed when I saw one new children’s book titled Eight Little Planets and another called How to Teach Grownups about Pluto that humorously teaches children to use the five stages of grief to get the adults in their lives to accept that Pluto is “gone.”

Yet there is no need for any type of grief because Planet Pluto is alive and well!

But the misinformation continues. Just today, an article in The Abbotsford News erroneously describes Pluto as an “icy stone plodding around the Kuiper Belt,” then states that “Thousands of objects have been catalogued so far in that outer belt, the Kuiper Belt, and at least 200 of them are bigger than Pluto.”

Far from an “icy stone,” Pluto is approximately 70 percent rock. And not a single object larger than Pluto has been discovered in the Kuiper Belt to date. Eris was initially thought to be larger but was found to be marginally smaller than Pluto when a team of astronomers observed it occult a star in 2010.

Yesterday, an article published in Science News titled "The Discovery of the Kuiper Belt revamped our view of the solar system" failed to even acknowledge the ongoing planet debate, quoting Mike Brown, David Jewitt, and Jane Luu, all of whom argued that Pluto “does not belong with the planets” without interviewing or mentioning a single planetary scientist who disagrees with this statement and favors the geophysical definition. The geophysical definition was not even mentioned once in the article.

It then goes on to say, "Pluto probably wouldn't be a member of the planet club much longer, the two (Jewitt and Luu) predicted. Indeed, by 2006, it was out” with no acknowledgement of the fact that most of the four percent of the IAU who voted on this were not planetary scientists but other types of astronomers, that an equal number of planetary scientists signed a petition rejecting the IAU decision, and that most planetary scientists today ignore that definition in favor of the geophysical one.

As noted before in this blog, the IAU definition requires a planet to orbit the Sun, not a star. This means that none of the 5,000 plus exoplanets discovered to date count as planets under their definition. Neither do rogue planets, which don’t orbit any star and therefore have no orbit to clear. In 2006, the IAU leadership promised to address the issue of defining exoplanets, but in 16 years, no such effort has been made.

Meanwhile, seven years have passed since Dawn’s flyby of Ceres and New Horizons’ flyby of Pluto, and the IAU has not shown any interest in using the data from these missions to reconsider the status of Ceres, Pluto, and other dwarf planets that could potentially have subsurface oceans capable of harboring microbial life.

Just two weeks ago, the IAU held yet another General Assembly that didn’t consider any of these issues.

While the stalemate continues over planet definition and the IAU continues to do nothing to correct the confusion their definition has caused, there has been one major positive development in the last year. Over budget and more than a decade late, the James Webb Space Telescope (JWST) finally and successfully launched in the last week of 2021.

On several occasions, JWST was almost canceled and/or defunded. Some astronomers even argued the project was not worth the trouble and expense. And even after launch, so many parts had to work correctly that many scientists felt genuine trepidation, afraid something would go wrong.

But nothing did, and today, JWST is orbiting the Sun one million miles from Earth and taking unprecedented, breathtaking photos of galaxies, stars, and planets. It just sent back a gorgeous image of Jupiter, and I know I’m not alone in hoping it one day images Pluto as well.

Whether with JWST or another observatory, it is only a matter of time before we discover dwarf exoplanets the size of Pluto. Will that discovery have any impact on the IAU?

JWST took much longer to launch than expected and faced numerous obstacles, including hurricanes and earthquakes, yet it is now giving us a whole new view of the universe. And one of its lessons is that good things sometimes take much longer than anyone desired or anticipated. But late does not mean never.

No matter how long it takes, we will not give up on a better, more inclusive planet definition that recognizes dwarf planets as a subclass of planets. We will NEVER go away. One way or another, the travesty of August 24, 2006, will be undone. In the meantime, we will continue to inform the media, textbook publishers, educators, and the general public that the debate continues, that the geophysical definition is the one preferred by most planetary scientists, and that the IAU definition is just one of many, not in any way more “official” or legitimate than any others in use.

For those interested in reading a very fair and balanced account of the history and current state of the planet definition debate, writer Matt Williams has published an excellent article on the website Interesting Engineering, which includes quotes by Alan Stern, Phil Metzger, and yours truly. I am very grateful to him for giving me a voice in his comprehensive article and encourage all Pluto fans and those interested in this issue to give the article a read.