December 21, 2009

TIPSHEET: The future of Pluto and Ceres

Three years ago, when the International Astronomical Union demoted Pluto to dwarf planet status, the unpopular decision was based on personal opinions and professional politics, not on rigorous scientific criteria that can clearly differentiate planets from lesser bodies, points out Vanderbilt astronomer David Weintraub. In the next decade, however, the amount of knowledge that we have about Pluto and another dwarf planet, Ceres, will change dramatically and this new information may affect our views of these objects and their status in the solar system as asteroids, dwarf planets or planets.

Three years ago, when the International Astronomical Union demoted Pluto to dwarf planet status, the unpopular decision was based on personal opinions and professional politics, not on rigorous scientific criteria that can clearly differentiate planets from lesser bodies, points out Vanderbilt astronomer David Weintraub. In the next decade, however, the amount of knowledge that we have about Pluto and another dwarf planet, Ceres, will change dramatically and this new information may affect our views of these objects and their status in the solar system as asteroids, dwarf planets or planets.

NASA’s New Horizon’s spacecraft, which flew past Jupiter in 2007, is scheduled to reach Pluto in 2015 and beam back close-ups of the distant object for the first time. At the same time, NASA’s Dawn spacecraft, launched in 2007, will provide the first up-close-and-personal pictures of Ceres, the largest object in the asteroid belt that stretches between Mars and Jupiter.

“By 2015, we’ll have visited both of these ‘dwarf planets,'” says Weintraub, author of the popular book Is Pluto a Planet? “They will no longer be distant dots in the sky. They will have recognizable faces; we will know much about their histories (inferred from their surfaces); we will understand Pluto’s atmosphere. They will gain full membership in the family of solar system objects of significant (spherical) size because we will know them so well.”

In the coming decade, Weintraub predicts that the new information about these objects will fill magazines, Twitter messages and blogs. These conversations will determine how the planetary science community will identify these objects and what specific words laypersons will use when discussing Pluto and Ceres in the future.

Media contact: David Salisbury, (615) 322-NEWS
david.f.salisbury@vanderbilt.edu