Universe Today: New Horizons Could Still Have More Adventures Ahead

 https://www.universetoday.com/157298/new-horizons-could-still-have-more-adventures-ahead/?fbclid=IwAR0RZ-jUrn4pcE1jWFWvS31I4dyCyKpojIeMr3nj8jnvy_Y-vMt_6-I0gWQ

Pluto Resistance Day

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.