Leave Pluto alone! That's the message astronomers all over the world are sending the International Astronomical Union (IAU). A recent discussion about whether Pluto should be cataloged as the 10,000th entry in the list of minor bodies in the solar system (Science, 8 January, p. 157) has alarmed planetary researchers, who worry that the public would see the move as a demotion for Pluto.
The Committee of the Division for Planetary Sciences (DPS) of the American Astronomical Society joined the chorus last week in a statement forwarded to the IAU, arguing that there is no compelling reason for the celestial body's declassification. "For now at least nothing should be done," says DPS chair Don Yeomans of NASA's Jet Propulsion Laboratory in Pasadena, California. Most solar system researchers agree, says Alan Stern of the Southwest Research Institute in Boulder, Colorado. Although Pluto is by strict definition a trans-Neptunian object, dozens of which have been found in the past decade, Stern sees no reason why it can't be called a planet, too.
The IAU isn't about to make a decision anytime soon. But it now knows how strongly some people feel about the subject. Says Yeomans: "There are nine planets, period."