Hype for Ultima Thule New Years Livestream!

I will be at JHUAPL for the flyby. Happy New Year!

Ultima Thule Part 2 - BRIAN MAY, Queen Guitarist & Astrophysicist

Winter Solstice 2018

Winter Solstice—that magical time when darkness gives way to light, and the Sun is symbolically reborn—is here once more. For Plutophiles, it caps a year of major victories in the fight for Pluto’s planet status while also heralding the flyby of New Horizons’ second target, Ultima Thule, now just days away.

This particular Solstice season is an unusually “spacey” one. It marks the 50th anniversary of the triumphant launch of Apollo 8 and its orbit around the Moon, setting the stage for the Apollo 11 landing just seven months later.

It was Apollo 8 that gave us the iconic “Earthrise” photo, showing the blue and white sphere of our planet rising as seen from lunar orbit.  More than anything else, that picture is a constant and powerful reminder that we are all one, that borders are artificial, that we share a common destiny. Since then, astronauts who have seen this view for themselves from the Moon, space shuttle and International Space Station have advocated giving everyone, especially world leaders, a chance to see it, understanding that seeing the world as one beautiful planet would forever alter their perspectives in a way that would benefit the world.

Like the Apollo missions, New Horizons and its flybys of Pluto and Ultima Thule remind us that humanity can do great things if we genuinely commit to doing them. The type of vision and persistence that made these missions so successful are badly needed today to unite this planet in the fight against climate change and the many social and political ills still facing so many people, the very things that are holding us back from fully becoming a space-faring species.

Too often, this time of year, which should unite us in recognition that we are all one planet and share a common destiny, instead divides us. In the US, people argue about whose holiday should receive the most recognition, who is a minority versus a majority, etc. This is genuinely sad because like eclipses, comet appearances, and meteor showers, solstices and equinoxes are phenomena everyone experiences. They remind us that all humans and all life share a common destiny. There is nothing wrong with celebrating cultural differences, but too often, these differences are emphasized to the point of obscuring that shared destiny. It is a case of seeing all the trees but failing to recognize they make up the single ecological system that is a forest.

If we can come together to put people on the Moon and control a probe four billion miles away, we can also come together to save this planet and begin a new era of exploration that will take us to the stars. That vision is still possible. Keep hope alive!

“Eyes to the blind!

Legs to the lame!

Luck to the poor!

Planetood for Pluto and all dwarf planets!

A Merry Solstice to everyone!”~an old Solstice greeting, as amended by Plutogirl

Should Pluto be a planet? - TMRO:Science Discovery 1.12

Engine burn puts New Horizons on track to Ultima Thule

Engine burn puts New Horizons on track to Ultima Thule

A Return Mission to Pluto? This Time to Stay

Variations on a Theme: What Do Earth and Pluto Share in Common? - Sky & Telescope

Variations on a Theme: What Do Earth and Pluto Share in Common? - Sky & Telescope: Nature loves to riff on existing motifs, even in the most unearthly of environments.

Ignore the IAU! Dwarf planets are planets, too!

This needs to be shared with the media, textbook publishers, educators, and science writers as much as possible!

New Horizons Science Chat discusses Ultima Thule flyby

New Horizons Science Chat discusses Ultima Thule flyby

More Comprehensive Interview with Phil Metzger on "Are We There Yet? The Space Exploration Podcast"

This is a more comprehensive interview with Phil Metzger on the show "Are We There Yet? The Space Exploration Podcast," broadcast on September 14, 2018.

http://www.wmfe.org/the-great-pluto-debate/91148

Phil Metzger interview on Pluto's planet status

https://amp.clickorlando.com/news/space-news/does-it-matter-if-pluto-is-a-planet-or-not?__twitter_impression=true

Please note there are two errors in the article below the interview video. The writer states that Eris was discovered by Mike Brown, when it was actually discovered by a group of three planetary astronomers--Brown, Chad Trujillo, and David Rabinowitz. Interestingly, both Trujillo and Rabinowitz reject the IAU planet definition.

Additionally, the writer reports that Eris is larger than Pluto. This is not the case. Eris was initially thought to be larger than Pluto but in 2010, a team of scientists led by Bruno Sicardy measured Eris's size when it occulted a star and found it to be marginally smaller than Pluto though 27 percent more massive. Being more massive, it is likely more rocky and therefore more planet-like.

New study rejects IAU rationale for demoting Pluto

New study rejects IAU rationale for demoting Pluto

New article in journal Icarus supports Pluto being classed as a planet

An article published by the University of Central Florida (UCF) reports on a new study published in the journal Icarus supporting Pluto's planet status and arguing that the reason behind the controversial IAU "reclassification" in 2006 is "not valid."

The lead author of the Icarus article is Dr. Philip Metzger of the University of Central Florida Florida Space Institute (FSI), a supporter of the geophysical planet definition. Other authors include Dr. Alan Stern of the Southwest Research Institute (SwRI) in Boulder, Colorado; Dr. Kirby Runyon, of the Johns Hopkins Applied Physics Laboratory (JHUAPL) in Laurel, Maryland; and Dr. Mark Sykes of the Planetary Science Institute (PSI) in Tucson, Arizona.

Unlike most of the four percent of the IAU who voted on this in 2006, these authors all are planetary scientists. Below is the UCF article on their study.

https://today.ucf.edu/pluto-planet-research/

Astronomy Pluto Puzzle

https://myscienceshop.com/product/gift/81179?utm_source=SilverpopMailing&utm_medium=email&utm_campaign=SA00_SCI_180903_P33855_PlutoPuzzle_ASY-DSC-SCI_Final&utm_content=&recipientID=Mjg1OTI1NjM3MjUxS0%20&spMailingID=35837764&spUserID=Mjg1OTI1NjM3MjUxS0&spJobID=1360254773&spReportId=MTM2MDI1NDc3MwS2

Pluto: The IAU Position is Opinion, not Fact

Contrary to what one is likely to read in various publications, textbooks, and online sites, Pluto did NOT lose its planetary status on August 24, 2006.

Today in the US, there is a lot of discussion of just what is “truth,” how one distinguishes between truth, opinion, and outright falsehood, and who gets to decide which version of a particular story is the “real one.”

In this context, it is appropriate to note that the overwhelming majority of publications, journalists, media outlets, textbook companies, and websites (including Wikipedia) got this all wrong 12 years ago when it comes to Pluto specifically and the definition of the term “planet” in general.

What happened on that day in 2006 is that 424 IAU members, most of whom were not planetary scientist but other types of astronomers, in an act that violated their organization’s own bylaws, voted to change the definition of planet. Of those 424, just 333 voted that dwarf planets are not planets at all but some other type of object entirely. 91 voted to class dwarf planets as planets.

Within days, an equal number of planetary scientists signed a formal petition rejecting the IAU decision. This group has maintained their position to this day, as is seen from presentations made in 2017 and 2018 to the Lunar and Planetary Sciences conference about the geophysical planet definition.

By saying that Pluto lost its status as the result of that vote by 424 people, the media gave the IAU a tremendous level of power that is completely unwarranted. They took a vote; so what? Another group, this one composed mostly of those who study planets, issued their own statement within days rejecting the IAU decision.

Why then is a vote by one group given a status of gospel truth while a vote by another, arguably more qualified group, barely gets any mention at all?

Does this remind anyone of the last presidential election, when some candidates were given national media attention for every tweet they wrote, no matter how ridiculous, while others had their increasing popularity completely ignored by the same mass media? If it doesn’t, it should!

If an asteroid had impacted Pluto and lobbed off part of it to the point that Pluto was no longer round—something that actually happened to proto-planets Vesta and Pallas in the belt between Mars and Jupiter—then it would make sense to say Pluto stopped being a planet on a particular day. If it suddenly lost a significant part of itself, Pluto would no longer be spherical, and one could legitimately question whether it would still count as being rounded by its own gravity.

But there was no such asteroid impact.

Frequently, when I and others who oppose the IAU definition explain the geophysical planet definition, according to which a planet is “a sub-stellar mass body that has never undergone nuclear fusion and that has enough gravitation to be round due to hydrostatic equilibrium regardless of its orbital parameters” (credit to planetary scientist Kirby Runyon for this definition), readers respond by stating, Wait! There is a third requirement, that the object has to clear its orbit.

Here is the problem. Who said there is a third requirement? Too many people act as though such a requirement was handed down by God on stone tablets. The truth is, it was not—it is simply the opinion of one group of scientists who prefer a dynamical definition, one that focuses on the influence objects have on other objects, over a geophysical definition, which instead focuses on an object’s intrinsic properties.

There is evidence that this “third requirement” was imposed by those who favor a dynamical definition for the specific purpose of excluding Pluto. This means that those who enacted it first decided the conclusion they wanted, then crafted a definition to fit their desired conclusion.

Commonly used by oil companies who commission studies about the connection between fossil fuel emissions and global climate change, this process looks like science but it is not science. Science does not choose a conclusion first, then fit the data to match that conclusion. Researchers paid by oil companies know where their money is coming from, which is why they arrange the data to fit their facts. This is exactly what took place in Prague in 2006 though the motivation was not money but imposing one particular view on the world.

Furthermore, the IAU definition was set up so that it could never be overturned. New Horizons was already on its way to Pluto when the 2006 vote took place. However, by making orbit clearing the determining factor for planet status, those who voted for this definition assured that no matter what was found at Pluto, no matter how many planetary features and processes it has, none of that would ever matter because Pluto does not clear or gravitationally dominate its orbit.

This is why even now, when the IAU is holding its first General Assembly since all the New Horizons data was returned in late 2016, no effort is being made by IAU insiders to revisit and possibly revise that decision.

And yes, this also applies to other dwarf planets.

Furthermore, to correct another erroneous assumption still circulating online, there are no known dwarf planets or Kuiper Belt Objects larger than Pluto. While Eris was initially thought to be larger, in 2010, a team of astronomers found it to be smaller than expected after measuring it occult a star. This method is regularly used by scientists to accurately find the size of a celestial object.

Even if there were dwarf planets larger than Pluto—and there may be some yet to be discovered—that would not have any impact on Pluto’s status. If such objects exist, they are all dwarf planets, a subcategory under the umbrella of planets—according to the geophysical definition.

An object cannot be defined by the presence of another object. A Mars-sized planet could be found far beyond Pluto, but that would not change what Pluto is. It would simply add another planet to our solar system.

Some people have a notion that our solar system cannot have “too many planets.” There is no scientific basis to this claim. The universe has billions of stars and billions of galaxies. The Milky Way alone likely has billions of planets—more planets than stars. Finding many of one thing does not mean that thing needs to be downgraded because there are “too many.”

Twelve years after this debacle, it is time to set the record straight. The status of Pluto and the question of what constitutes a planet are both matters of ongoing debate. Neither position is more “official” or legitimate than the other. The IAU claim that its definition alone is “truth” is based on nothing more than authoritarianism—an insistence that they and only they get to decide this issue—this in spite of the fact that unlike those who oppose them, the IAU never sent a spacecraft to any planet.

Setting the record straight means getting the word out to textbook publishers, educators, authors, media outlets, planetariums, observatories, and members of the public that the only fair and balanced way to present this issue is as a legitimate debate with two sides. Yes, some people genuinely believe Pluto lost its planet status on August 24, 2006. But that is one view, one opinion, not objective reality, not fact or “truth.” While a controversial debate took place that day, it did not alter what is out there. Those who hold to the geophysical definition—many of whom are the world’s leading planetary scientists—consider Pluto to never have stopped being a planet, and their view deserves as much respect and acknowledgement as that of their opponents.

Let’s get the message out there!

Pluto’s Earth-like glaciers puzzle scientists

Pluto’s Earth-like glaciers puzzle scientists

Planetary Scientists Object to Use of Term "Planet 9" for Possible Objects Beyond Pluto

In the August 5, 2018, edition of Planetary Exploration Newsletter, a publication of the Planetary Science Institute, a group of planetary scientists expressed their objection to the insensitive use of the term "Planet Nine" to refer to one or more hypothetical planets beyond Pluto. Their statement points out that the IAU planet definition is "far from universally accepted," and adds that using the term "Planet Nine" for an object other than Pluto is disrespectful to the legacy of Clyde Tombaugh, who discovered Pluto, which is still viewed by many as the solar system's ninth planet.

Yes, according to those who hold to the geophysical planet definition, Pluto is actually the solar system's tenth planet rather than its ninth. This is because Ceres was not known to be spherical and therefore a small planet until it was observed with the Hubble Space Telescope. Now that we know Ceres is actually the solar system's fifth planet, this makes Jupiter its sixth, Saturn its seventh, Uranus its eighth, Neptune its ninth, Pluto its tenth, and so on. Unfortunately, Tombaugh did not live to see Ceres's upgrade, and for the better part of a century, Pluto was known as the solar system's ninth planet. While today that designation is more colloquial than scientific, even from a geophysical point of view, millions of people continue to see Pluto as planet nine. Personally, I like to call it "the ninth planet that is really the tenth planet."

On January 20, 2016, Mike Brown put out a press release announcing his theory of a hypothetical giant planet in the outer solar system and deliberately used the term "Planet Nine" in the title of the press release in an effort to establish this name universally. This was clearly the act of someone who is media savvy and understands public relations. He set out to establish a fait d'accompli that inherently endorsed his erroneous view that all or most planetary scientists accept the IAU designation and its corollary that the solar system has only eight planets. When I urged several media outlets to use the term "Planet X," the traditional term for a hypothesized but undiscovered world, they claimed the world already knows it as "Planet Nine" and would not know what was being referred to by the term "Planet X"--proving Brown's establishment of a self-fulfilling prophecy had worked--at least temporarily.

But two-and-a-half years later, his planet has yet to be found. And finally, planetary scientists are speaking up and appropriately requesting the use of a fair and balanced term instead of a loaded, biased one.

Here is the text of their petition, which can be found at https://planetarynews,org

EDITORIAL: ON THE INSENSITIVE USE IF THE TERM "PLANET" 9 FOR OBJECTS
BEYOND PLUTO

We the undersigned wish to remind our colleagues that the IAU planet
definition adopted in 2006 has been controversial and is far from
universally accepted. Given this, and given the incredible
accomplishment of the discovery of Pluto, the harbinger of the solar
system's third zone - the Kuiper Belt - by planetary astronomer
Clyde W. Tombaugh in 1930, we the undersigned believe the use of the
term "Planet 9" for objects beyond Pluto is insensitive to Professor
Tombaugh's legacy.

We further believe the use of this term should be discontinued in favor
of culturally and taxonomically neutral terms for such planets, such as
Planet X, Planet Next, or Giant Planet Five.

Paul Abell
Michael Allison
Nadine Barlow
James Bauer
Gordon Bjoraker
Paul Byrne
Eric Christiansen
Rajani Dhingra
Timothy Dowling
David Dunham
Tony L. Farnham
Harold Geller
Alvero Gonzalez
David Grinspoon
Will Grundy
George Hindman
Kampalayya M. Hiremath
Brian Holler
Stephanie Jarmak
Martin Knapmeyer
Rosaly Lopes
Amy Lovell
Ralph McNutt
Phil Metzger
Sripada Murty
Michael Paul
Kirby Runyon
Ray Russell
John Stansberry
Alan Stern
Mike Summers
Henry Throop
Hal Weaver
Larry Wasserman
Sloane Wiktorowicz

Topographic maps reveal surface details on Pluto and Charon

Just in time for the third anniversary of New Horizons' Pluto Flyby!

Topographic maps reveal surface details on Pluto and Charon

NASA | Charon at 40: The Discovery of Pluto’s Largest Moon

Pluto is not a giant comet!

Within the past week, you may have seen reports of a study that some scientists say indicates Pluto is actually a giant comet that was formed by the aggregation of billions of comets. This is not true! What the study actually found is that both Sputnik Planitia, the left side of Pluto's heart feature, and Comet 67P/Churyumov-Gerasimenko, both were found to have the same isotope of nitrogen on their surfaces. While this is true and suggests they may originate in the same region of the solar system, it does not mean Pluto is a giant comet! In this case, people erroneously drew a conclusion without sufficient data to confirm that conclusion.

Below is a good article by planetary scientist Philip Metzger explaining why Pluto is not a giant comet.

Icy Worlds and Stars with Long Hair - Philip Metzger: Are icy worlds like Pluto just comets because they're made of ice? This post looks at what planets made of and looks at the amazing insides of icy worlds.

Tom Siegfried, former editor of Science News: Pluto's Demotion Ignores Astronomical History

They keep on coming! Here is yet another terrific article about the issue of planet definition and the many problems with the 2006 IAU definition, this time by Tom Siefried, former editor of Science News.

https://www.sciencenews.org/blog/context/pluto-demotion-ignores-astronomical-history?tgt=nr

Siegfried's article refers to a new scientific paper by Philip Metzger, Mark Sykes, Alan Stern, and Kirby Runyon, which can be found at https://arxiv.org/abs/1805.04115.

Guest Blog: Revisiting the definition of a planet - Astronomy Magazine - Interactive Star Charts, Planets, Meteors, Comets, Telescopes

This is my response to Ethan Siegel's May 8 Forbes.com article, "You Won't Like the Consequences of Making Pluto a Planet Again," posted on Astronomy Magazine's blog site.

Guest Blog: Revisiting the definition of a planet - Astronomy Magazine - Interactive Star Charts, Planets, Meteors, Comets, Telescopes

An organically grown planet definition: From Astronomy magazine

An organically grown planet definition: h1.headline {text-align:center;} .subheading {text-align:center;} .byline {text-align:center;} .article .fromIssue {text-align:center; margin-top: 10px;} .article {padding-top:49

Should you care about Pluto? We asked NASA's Alan Stern and astrobiologist David Grinspoon

Chasing New Horizons: An epic exploration to a strange new world

Chasing New Horizons: An epic exploration to a strange new world

Close to three years after the historic New Horizons Pluto flyby wowed the world, mission principal investigator Alan Stern and astrobiologist and mission science team member David Grinspoon tell the riveting story of a monumental exploration 26 years in the making in their new book Chasing New Horizons: Inside the Epic First Mission to Pluto.

Much like a novel, the book starts with a crisis, the loss of contact with the spacecraft just ten days before the flyby, then goes back to the beginning of everything and narrates the story chronologically, from Stern’s birth through the first thoughts of a Pluto mission just as Voyager 2 visited Neptune in 1989, and the many twists and turns, setbacks and victories that culminated in the triumphant 2015 Pluto flyby.

Stern and Grinspoon are scientists, yet this book is first and foremost a narrative, one that takes readers along on a multi-decade effort that started as a vision by young scientists whose efforts were stymied by a powerful and often set-in-its ways establishment.

From the initial “Pluto Underground” visionaries to the steadfast team members who overcame what seemed like never-ending challenges, readers are familiarized with the many resourceful, persistent characters who made the mission happen, to the point that it feels like we know them personally and are there with them during the journey.

At times, Stern and Grinspoon make references to popular science fiction such as Star Wars and Star Trek, an interesting choice given that Chasing New Horizons often reads and feels like a Star Trek movie. Like chief engineer Scotty, the mission team always manages to find a way to work within what seem to be impossible limitations in terms of time and budget.

One problem is successfully dealt with only to lead to another. If just one of many cancellations or crises or decisions had gone a different way, there would have been no Pluto mission at all, the writers note while recounting each of the do-or-die moments.

Much like the discovery of Pluto itself by Clyde Tombaugh, the story of New Horizons is a tale of persistence. When he arrived at Lowell Observatory in 1929, Tombaugh was told by a professional astronomer that he was “wasting his time” searching for an undiscovered planet. In 2000, after Stern’s team had worked on a mission proposal for 18 months, NASA Associate Administrator for science Ed Weiler canceled the entire Pluto project, declaring it “dead, dead, dead.”

But the “Pluto Underground” refused to accept a death sentence. Humorously, the writers titled the chapter immediately following this declaration, “The Undead.”

In total, proposed Pluto missions were canceled five times. If not for the incredible persistence of those committed to making one happen, the world today would still know little about this mysterious world.

“We really need an orbiter that can map 100 percent of everything in the Pluto system. We want to bring radar to look down to the ice; we want to bring mass spectrometers to sample the atmosphere; we want thermal mappers,” Stern told Spaceflight Insider, New Horizons raised so many questions about Pluto and its moons that Pluto scientists are already laying the groundwork for a Pluto orbiter.

By raising the strong possibility that Pluto has a subsurface ocean, the mission has put Pluto on the radar screen of scientists who study ocean worlds and want to visit a broad sample of these worlds, Stern noted.

New Horizons was about more than science; it was about the motivation to explore a “strange new world,”to “go where no one has gone before.” The motivation to explore kept the dream alive even when everything seemed lost.

When it finally happened, the flyby was as much about aesthetics and beauty as it was about science, Stern and Grinspoon note. With its diverse surface features and iconic heart-shaped region named for Clyde Tombaugh, Pluto turned out to be a beautiful, breathtaking world.

Recounting an especially poignant moment in the epilogue “Coda: A Final Discovery,” Stern and Grinspoon recount New Horizons’ unanticipated human impact as a new generation’s Apollo experience with a moving story about how the flyby inspired a Florida teenager to go from failing school to being an A student upon deciding he wanted a career in space exploration.

“The book is really an adventure story about how a bunch of young scientists who were determined managed to overcome the system and make the farthest exploration in the history of human exploration. And it’s a story about how you build space missions and plan flybys and also about the science,” Stern said. “It’s three stories woven together.”

"Yes, Pluto is a Planet"--Terrific Washington Post Article by Alan Stern and David Grinspoon

This Washington Post article by Alan Stern and David Grinspoon does a great job in presenting the case for Pluto's planet status. This is a must read for Pluto supporters and advocates of the geophysical planet definition.

https://www.washingtonpost.com/news/speaking-of-science/wp/2018/05/07/yes-pluto-is-a-planet/?commentId=9d9f6b96-e408-4be7-894a-409ae4821e8c&utm_term=.1da648439ae8

Chasing New Horizons by Alan Stern and David Grinspoon

Chasing New Horizons: Inside the Epic First Mission to Pluto, co-written by New Horizons principal investigator Alan Stern and David Grinspoon, a member of the New Horizons science team, will be published and available for purchase as of May 1, 2018. I am currently reading the book, which I will review for Spaceflight Insider, which I will then link to this blog.

The fascinating story of New Horizons is a tribute to the persistence and passion of the scientists who first came up with the idea of a mission to Pluto--all the way back in 1989!

Learn more about the book and order it from its official page at https://read.macmillan.com/lp/chasing-new-horizons-by-alan-stern-and-david-grinspoon/ .

The book has a Facebook page at https://www.facebook.com/ChasingNewHorizonsBook/

A schedule of Stern and Grinspoon's book tour can be found at https://alanstern.space/events/ . At the bottom of this page, you can sign up for regular email updates on the authors' book talks and related events.

Major congratulations to Stern and Grinspoon on the book's publication. Like all things Pluto, the New Horizons mission has an inspiring and exciting story.

Geophysical Planet Definition: Discussion led by Kirby Runyon

Presentations and discussion at the 2018 Lunar and Planetary Science Conference (LPSC) about the geophysical planet definition and the 100s of objects it recognizes as planets within our Solar System. Pluto IS a full-fledged planet (and so are a lot of other round worlds)!

Debunking an Urban Legend of Asteroidal Proportions - Philip Metzger

Planetary scientist and physicist Philip Metzger has written a very informative blog entry debunking misconceptions about the alleged past demotion of asteroids from planets to non-planets. Below is the link to his entry, which summarizes a paper he cowrote with fellow planetary scientists Mark Sykes, Alan Stern, and Kirby Runyon for publication in a science journal and for a public presentation, "Planetary Taxonomy: The Geophysical Planet Definition," which will be presented tomorrow, Sunday, March 18, 2018, at the Lunar and Planetary Sciences Conference 2018.

Debunking an Urban Legend of Asteroidal Proportions - Philip Metzger:

A pre-print of the whole journal article is available for download here: 

http://www.philipmetzger.com/blog/wp-content/uploads/2018/03/Preprint_Asteroids-reclassified-as-non-planets_Metzger-et-al.pdf

Just how unscientific has the IAU been about planet definition over the years? Metzger tells this shocking story:

"I mentioned above about authorities 'imposing decisions on individual scientists.' Does that really happen? Well, the IAU tried to make it happen. A colleague who is on the editorial board of one of the major planetary science journals told me that the IAU wrote to the editors and asked them to deny publication to any manuscript that doesn’t bend the knee to accept the IAU’s definitions. My colleague says the editors decided to reject the request. Thankfully so! Scientific freedom lives to fight another day."

Today: Pluto Discovery Telescope Grand Renovation at Lowell Observatory

Today, the Lowell Observatory in Flagstaff, Arizona, where Pluto was discovered 88 years ago, is holding a Grand Reopening celebration for the 90-year-old Pluto Discovery Telescope, which just completed a year of renovation.

https://lowell.edu/event/pluto-discovery-telescope-grand-reopening/?instance_id=650

Pluto at 88: The Debate Continues

Pluto, known to humanity just since 1930, has been a solar system planet for four billion years but was discovered as one 88 years ago today, on February 18, 1930, by astronomer and planetary scientist Clyde Tombaugh at the Lowell Observatory in Flagstaff, Arizona.

An article published yesterday in TheWashington Post reports that six-year-old Cara Lucy O’Connor of Ireland, with the help of her teacher, wrote a letter to NASA asking the agency to reinstate Pluto as a planet. Based on Cara’s statements in the article, it is fair to say she knows more about the solar system than most adults and maybe even more than the 333 non-planetary scientists at the 2006 IAU General Assembly who voted for the resolution that says dwarf planets are not planets at all.

Especially interesting are the comments written in response to the article, many of which are replete with the same errors and misconceptions that have now been repeated for 11-and-a-half years.

While Cara cannot be expected to know this, the controversial vote to demote Pluto was not made by NASA but by four percent of the IAU. Contrary to some people’s comments, NASA does not formally accept or reject the IAU decision. Instead, the agency leaves that decision up to its individual scientists. This is why some NASA websites continue to include Pluto as a planet while others do not.

Most scientists on NASA’s New Horizons mission do consider Pluto and all dwarf planets to be a subclass of planets. Since this group actually flew a probe to Pluto, the last thing NASA is likely to do is tell them they are wrong. Thanks to the mission team, humanity has seen Pluto up close and has learned more about this geologically active world than was known prior to the 2015 flyby during the 85 years since its discovery.

Among the misconceptions repeated in the comments are that there are Kuiper Belt Objects out there that are larger than Pluto (there are none known though even if there were, that would not preclude all of them from being considered planets), that the “experts” of the world made a scientific decision that has broad consensus among scientists ( they didn’t, and it doesn’t), that being in a belt of objects is the primary determinant of what an object is (this completely ignores an object’s intrinsic properties), that the Lambda factor in Alan Stern and Hal Levison’s 2000 paper precludes dwarf planets from being planets (it doesn’t), that Stern alone has a personal interest in Pluto being classed as a planet (he is far from alone; most planetary scientists take this same position), and that the number of planets has to be kept small because people can remember only at most ten numbers in a sequence (this is erroneously based on the notion that memorizing a list of names is the way to teach kids about the solar system).

In many ways, the IAU vote is a lot like climate change science funded by oil companies and other industries with special interests in a particular outcome. Those working on these studies know where their money is coming from and set out to “prove” a foregone conclusion in favor of their funders. So, too, the four percent of the IAU who voted in 2006 had a prior agenda of excluding Pluto from the list of planets. They then crafted a definition that met the conclusion they had already decided on. That is where the orbit clearing “requirement” came in. What we have here is something that looks like science but is not the real thing.

Some writers mock Cara with condescending remarks about how scientists should not give in to the “whim” of a child. Others frighteningly buy into the notion that the IAU is the body of experts who have been “empowered” by the world to make such decisions.

Nobody has so “empowered” the IAU. The organization appointed itself to do this, in spite of the fact that its true mission is to “safeguard the science of astronomy.” As I have noted many times, most of the 424 IAU members who voted in 2006 were not planetary scientists but other types of astronomers—hardly the ones who should be telling the world what is and is not a planet. IAU definitions are intended for internal organizational use, not meant to be imposed on the entire world. And no one raises the issue that science is not dictated by decree of “authority.” Galileo addressed this notion 400 years ago, yet it seems some have not learned the lessons of his experience. Like today’s planetary scientists, he observed phenomena that contradicted the decrees of the “authorities” of his day. He saw that Jupiter has moons, that Venus has phases, that the Moon has craters and diverse features, that the Milky Way is made up of numerous individual stars—and was not afraid to publicly present his findings in contradiction to those “authorities.”

Other comments include the old staples about how “Pluto doesn’t care” what it is called, a need to accept change based on new discoveries, claims that Pluto is fundamentally different from the larger planets, and even political statements regarding Barack Obama and Donald Trump.

I have no idea what position, if any, these politicians and others take regarding Pluto’s status. What I do know is that whether or not Pluto is viewed as different from the other planets is largely based on the criteria people choose for basing their decisions. Pluto has active geology, cryovolcanism, an atmosphere, interaction between that atmosphere and its surface, and a possible underground ocean. It is geologically layered into core, mantle, and crust. As for its eccentric orbit, Mercury also does not orbit on the same plane as most solar system planets, and many giant exoplanets in individual systems all orbit on different, far more eccentric planes than Pluto.

The argument that “Pluto doesn’t care” what it is called is a straw man. No one is saying Pluto does care. Instead, the point is that we should care because the public is being sold a bill of goods by being taught that one view in an ongoing debate is gospel truth. This is the tremendous disservice to the public caused by the IAU vote.

Why do so many textbooks, media outlets, websites, and educational materials report nothing about the ongoing debate over the status of dwarf planets, instead blindly falling in line with the IAU position? Why did Encyclopedia Britannica wait for the IAU vote to publish its 2006 edition? Both children and adults are being taught a falsehood as truth. They are being led to believe there is consensus on one specific interpretation of the solar system when this is far from the case.

The IAU has had its chance to rectify its mistake of determining what Pluto is before any spacecraft ever visited it and has repeatedly refused to do so. Apparently, only some new discoveries merit reopening the debate. Eris’s discovery does, but New Horizons’ findings of planetary processes on Pluto apparently do not.

Instead of giving this organization a degree of power it has never earned, it is time to look elsewhere for insight into what constitutes a planet. While this is an ever-evolving question that will always change with new discoveries, those we should look to for guidance are the scientists who actually gave us a first-hand view of Pluto, not a group of bureaucrats concerned largely about preserving their own power.

Finally, we often hear the argument that if Pluto were discovered today, it would not be considered a planet. This, too, is an interpretation. As we can see, the status of Eris, discovered in 2005, set off the latest round of this debate, which continues to this day. If Pluto had been found today, scientists would quickly be able to view it with the Hubble Telescope and determine it is spherical. They would be able to tell it is part of a binary planet system with Charon that also has four more tiny moons. They would be able to determine Pluto has an atmosphere and even visit it up close with a probe. It is fair to say that if Pluto were discovered today, the same debate over its status would occur.

Cara’s precociousness is reminiscent of that showed by another young person, who built his own telescopes, observed Mars and Jupiter, and drew very accurate depictions of those planets that earned him the job of searching for a new planet at Lowell Observatory—a planet he discovered 88 years ago today. Clyde Tombaugh never wavered on his position that Pluto is a full-fledged planet. Neither should Cara, and neither should we.