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International Astronomical Union to Decide: What Is a Planet? - Audio Clips
08.16.06
 
The International Astronomical Union, currently meeting in Prague, is expected to vote on the definition of a planet. The organization, which names planets and moons, is considering a plan to establish that our solar system has 12 planets.

The organization proposes that two conditions must be met for an object to be called a planet. It must orbit around a star, but must not be a star itself. And the object must be massive enough for its own gravity to pull it into a nearly spherical shape.

The designated dozen would include eight of the traditional nine -- Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune -- plus Ceres, the largest known asteroid. Pluto would still be a planet, but in a category called "plutons." That category would also include two other planetary newcomers: Charon, formerly known as Pluto's moon, and the recently-discovered 2003 UB313.

CUT 1 – DR. MIKE BROWN OF THE CALIFORNIA INSTITUTE OF TECHNOLOGY, AND HIS COLLEAGUES ANNOUNCED THE DISCOVERY OF 2003 UB313. THEIR RESEARCH WAS PARTLY FUNDED BY NASA. BROWN SUMS UP WHAT THE PROPOSAL WOULD DO TO THE PLANETARY LINEUP.
Running time: :27
OUT: "ITS OWN RIGHT'"
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Transcript of CUT 1: "If passed, the resolution will make anything in the solar system that's large enough to be round, due to its own gravitational pull, into a planet. So that would add the nine things that we currently know of as planets would still be planets. And it would add three more. It would add Ceres, the largest asteroid, and it would also add 2003 UB313, the large Kuiper Belt object that was discovered last year in the region outside of Neptune. It would also add Pluto's moon, Charon, as a bona fide planet in its own right."

CUT 2 – DR. MIKE BROWN SAYS THAT THE INTERNATIONAL ASTRONOMICAL UNION'S PLAN WOULD RESULT IN DRAMATIC CHANGES.
Running time: :09
OUT: "REWRITE EVERYTHING"
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Transcript of CUT 2: "Oh, there's no question that if this proposal's accepted, this is a major departure from what we've considered planets all along, and it will rewrite everything."

CUT 3 – DR. STEVE EDBERG, A PLANETARY ASTRONOMER AT NASA'S JET PROPULSION LABORATORY, SAYS THE DEBATE OVER THE DEFINITION OF A PLANET WAS PROMPTED BY A FLURRY OF RECENT DISCOVERIES OF OBJECTS IN OUR SOLAR SYSTEM .
Running time: :08
OUT: "AND EXPANDING"
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Transcript of CUT 3: "It just means that our science, the science of planetary astronomy, is alive and well and expanding."