Today, 24 August, is “Pluto Demotion Day”!

Today, 24 August, is “Pluto Demotion Day”! August 24, 2019


Pope-Scope on Mt. Graham
The 1.8 meter Alice P. Lennon Telescope and its Thomas J. Bannan Astrophysics Facility are known, together, as the Vatican Advanced Technology Telescope (VATT) — or, sometimes, as the “Pope-Scope.” The VATT is a Gregorian telescope observing in the optical and infrared, situated on Mount Graham in southeastern Arizona. VATT is part of the Mount Graham International Observatory and is operated by the Vatican Observatory, one of the oldest astronomical research institutions in the world, in partnership with the University of Arizona.  (Wikimedia Commons public domain photograph)


Today marks the thirteenth anniversary of the day in 2006 that the International Astronomical Union (IAU), announced a new definition for the term planet and, at the same time, decreed that Pluto no longer met the criteria for being classified as a planet in our solar system.  Pluto Demotion Day, it’s been called since then.  A day that, for more than a few, will live in infamy unless and until Pluto is restored to full planetary status.


Here is an article on the topic:


“Why Pluto is no longer a planet (or is it?)”


The best sustained discussion that I’ve read of the demotion of Pluto from full planetary status — which pretty much means that it’s the only sustained discussion of the subject that I’ve read — occurs (I believe) in Guy Consolmagno and Paul R. Mueller, Would You Baptize an Extraterrestrial?: . . . and Other Questions from the Astronomers’ In-box at the Vatican Observatory.


Father Mueller, a Jesuit priest, earned degrees in physics, philosophy, theology, and the history and philosophy of science at Boston University and the University of Chicago.  Guy Consolmagno is a Jesuit brother who earned undergradduate and master’s degrees in earth and planetary science at the Massachusetts Institute of Technology (MIT) and a Ph.D. in planetary science from the University of Arizona.


Brother Consolmagno, who currently serves as Director of the Vatican Observatory and President of the Vatican Observatory Foundation (as, in more popular parlance, the “Vatican Astronomer”), was a member of the committee that downgraded Pluto to the status of a “dwarf planet” or even a “Trans-Neptunian Object,” and he outlines the basic arguments that led the committee to its unpopular decision.  I have to confess that I found them more persuasive than I had expected.


Brother Consolmagno was also the very affable keynote speaker at the Interpreter Foundation’s  2016 Science & Mormonism Symposium: Body, Brain, Mind & Spirit, which was held on 12 March 2016 on the Orem, Utah, campus of Utah Valley University.  Entitled “Astronomy, God, and the Search for Elegance,” his was an excellent speech, and I commend it to your attention:


Brother Guy Consolmagno SJ – Keynote Address: Astronomy, God, and the Search for Elegance




And now for some other news from our solar system:


“Turbulent storm clouds disrupt Jupiter’s colorful appearance”




I don’t want to appear provincial, though.  So here’s some news from beyond our solar system:


“NASA discovers potentially habitable planet: A “super-Earth” 31 light-years away could have the right conditions to support liquid water and possibly sustain life.”


“Exoplanets could have better conditions for life than Earth, study says”


“Black hole gobbles up neutron star, causing ripples in space and time”



Browse Our Archives

Follow Us!