Why Pluto had to die - a planet assassin tells all

“Pluto is dead.”

So eulogized Caltech planetary astronomer Mike Brown in August, 2006. The International Astronomical Union had just voted overwhelmingly to kick Pluto out of the Sun’s family of planets and designate it a dwarf planet. The decision had been prompted by Professor Brown’s own 2005 discovery of Eris, an icy world more massive than Pluto, beyond the orbit of Neptune.

The demotion triggered world-wide outrage at the thought of the “death” of the ninth planet.

Since that day Brown has mostly enjoyed the role of “Pluto Killer” and has been featured in the New Yorker, the New York Times and Discover magazine; he was even named to Wired Online's Top Ten Sexiest Geeks in 2006. He has also written How I Killed Pluto And Why It Had It Coming, a memoir about his search for planets and his newfound fame or infamy. And while he plays this role with good humour—on Twitter he is @plutokiller—he is also a serious defender of the science behind the decision, arguing against those who say there is no logic behind the demotion.

On May 19, 2012, Brown will give a special public lecture titled: Pluto is Still Dead and Other Good News. The free talk is from 8 pm to 9:15pm and will be held in the J.J.R. MacLeod Auditorium, Medical Sciences Building, 1 Kings College Circle, on the St. George campus of the University of Toronto.

The talk is sponsored by the U of T’s Dunlap Institute for Astronomy & Astrophysics (DI) and the Department of Astronomy & Astrophysics (DAA). Brown's notoriety provides the DI and DAA with a unique opportunity to engage the public in science, said Dunlap Institute Professor Shelley Wright.

"The subject of Pluto's status as a planet strikes a chord, even today,” Wright said, “and hosting Mike Brown is a great way to reach a broad audience through an event that was front page news."

In his talk, Brown will describe how most of the world has moved on after the raucous debates about Pluto and dwarf planets—even if an occasional "Bring back Pluto!" t-shirt can be seen in lecture audiences. He will also talk about how most people still have little understanding of what happened to Pluto and why. Was it just too small? Was it too close to Neptune? Are astronomers just mean and arbitrary? And if we grew up remembering the order of the planets using the mnemonic device, “My Very Energetic Mother Just Served Us Nine Pizzas”, then what exactly is she serving us today!?

Brown will answer all of these questions while giving a history of discovery in the outer solar system and explaining how the demotion makes sense in the context of the solar system of today.

Prior to the lecture, visitors can view the Sun through telescopes or attend free planetarium shows. Following the lecture visitors can purchase copies of How I Killed Pluto for Brown to sign, attend planetarium shows or tour the observatory atop the McLennan Physical Labs building.

The Department of Astronomy & Astrophysics is engaged in a wide range of observational and theoretical research on solar system dynamics, stars, stellar systems, the interstellar medium, the Milky Way Galaxy, galaxies, quasars, clusters of galaxies, cosmology, and problems in general relativity. The Department has close ties with the Canadian Institute for Theoretical Astrophysics (CITA), and the Dunlap Institute for Astronomy and Astrophysics (DIAA) which is located in the same building.

The Dunlap Institute was created in May 2008 in order to continue the Dunlap family’s commitment—born in 1935 with the opening of the David Dunlap Observatory—of developing innovative observational methods, and designing and developing new instruments, telescopes and observatories. It also continues  the observatory’s commitment to outreach and education—to the University of Toronto community, the Greater Toronto area, and the nation as a whole.

Click here for a detailed schedule, map, and to sign up for a planetarium show.

Click here for more about Mike Brown.