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BYU professor asks "Is Pluto a Planet?" in lecture Aug. 4

In connection with the International Year of Astronomy, Denise Stephens, an assistant professor in Brigham Young University’s Department of Physics and Astronomy, will be presenting a lecture, “Is Pluto a Planet?” The lecture will be Tuesday, Aug. 4, at 7:30 p.m. in the auditorium of the Harold B. Lee Library, Room 1060.

The lecture is free to the public, and seating will be open at 7 p.m. There will also be a question-and-answer session following the lecture until 9 p.m. Telescopes on the deck of the Eyring Science Center will be open until 10 p.m., weather permitting.

This lecture will mark the three-year anniversary of the meeting of the International Astronomical Union in Prague for their general assembly that excluded Pluto as a planet. While some have welcomed this controversial change as the only possible outcome for Pluto, others have openly protested and rejected the decision.

“In this talk, I'll cover the events and the discoveries that forced the IAU to make a decision on what constitutes a planet,” Stephens said. “I'll go into the history of what happened at the IAU meeting and the many resolutions that were introduced to try and save Pluto. We'll talk about the vote that declassified Pluto, and I'll discuss the reaction of both the public and astronomers to the decision.”

“Finally, we'll talk about whether or not it really matters what you call Pluto. Regardless of whether you believe Pluto is a planet or not, this talk will give you the history and information you need to understand why astronomers did what they did in 2006 and the impact of that decision today,” she said.

Stephens received her bachelor’s degree in physics in 1996 from BYU and her master’s and doctoral degrees in astronomy from New Mexico State University. The Astronomy Department at NMSU was founded by Clyde Tombaugh, the discoverer of Pluto, so Stephens has been in a unique position to observe and meet many of the key players who were involved in the discoveries and decisions that eventually led to the declassification of Pluto.

She joined the BYU faculty in 2007, where she continues to do research on the atmospheres of brown dwarfs, the characteristics of objects in the Kuiper Belt and the moons of Pluto.

For more information visit or call Denise Stephens at (801) 422-2167.

Writer: Brandon Garrett


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