So Pluto will not be counted among the asteroids and other second-class citizens of the solar system. After weeks of e-mailed arguments among planetary scientists and media reports that mostly milked the episode for laughs, the Small Bodies Names Committee of the International Astronomical Union (IAU) decided last week not to assign Pluto a minor planet number. The smallest of the Sun's nine planets is therefore spared the indignity of what would undoubtedly have been an ill-advised demotion.

The controversy's originator, Brian Marsden, has for years unsuccessfully tried to persuade fellow astronomers that Pluto should be counted as a minor planet. As director of the Harvard Smithsonian Astrophysical Observatory's Minor Planet Center in Cambridge, Massachusetts, he proposed that the upcoming designation of the 10,000th minor planet, whose cataloguing is the centre's responsibility, be given to Pluto — partly as an honour, and also to recognize that the icy planet just as properly belongs to a class of Trans-Neptunian Objects (TNOs) orbiting at the far reaches of the Solar System.

It was unfortunate that the proposal was erroneously linked in some press stories with the work of two IAU committees currently considering a numbering system for TNOs and the scientific definition of a planet, and even more so that some media began reporting that Pluto had already been downgraded. The community felt obliged to respond and, finally, IAU General Secretary Johannes Andersen slammed the door shut by issuing his own statement that the naming committee had squashed the suggestion.

From the beginning, most planetary astronomers never considered the matter controversial in a scientific sense, and will be happy to get back to work. Marsden appears contrite about his fruitless stirring. But his misjudgement was not scientific: the distinctions between Pluto and TNOs appear insignificant and need to be clarified. Marsden merely underestimated astronomers' proprietorial attachment to this lonely object.