The committee had to formulate the question to be voted on by the whole body. The possibility exists that the proposal will be voted down, but that's not too likely (hooray!). Most members will just be glad to get this issue settled once and for all.
The reason this is good news for some geeks (uh, like me for example) is that the proposal could have been, "shall the number of planets be reduced to eight, and Pluto and other bodies reclassified as KBOs" -- or something.
There wasn't any logical way to do that, since this was about defining "planet". There could be a body orbiting the Sun that is larger than Mercury, but very far out, or very dark, or in retrograde orbit.
Some say that the residuals in Neptune's motion can be eliminated by dropping the anomalous observations (which it seems to me are something like 100 years old), with one astronomer even claiming that the issue of any remaining planet X is a psychological one.
Some take the view that orbits like that of Sedna indicate a large body kickin' stuff out of the Oort Cloud, or the Kuiper Belt. My wild guess is, the residuals are real, but that Tombaugh's exhaustive search for it didn't find it because it is in retrograde orbit. :')
Xena gets a planet!
The First Mission To The Last PlanetOf our solar system's nine planets, tiny, frozen Pluto is the only one that's never been visited by a spacecraft. And at three billion miles away, the runt of the planetary litter is incredibly difficult to study from Earth. But this year NASA and the Johns Hopkins University Applied Physics Laboratory will check the iceball off their exploration agenda as they launch New Horizons—a compact, 1,000-pound spacecraft that they hope will offer some insight into the orb that, right now, is just a blurry smudge of light in the outer reaches of space.
December 2005
Long-Distance Linkage
New Horizons project manager Glen Fountain stands behind the door of the Mission Operations Center at the Johns Hopkins Applied Physics Laboratory near Baltimore, from which members of the New Horizons team will track all of the spacecraft's activity. Because the probe will travel about three billion miles to reach Pluto, all outgoing commands and incoming data will be transmitted through NASA's Deep Space Network of antenna stations.
Testing 1, 2, 3
If the New Horizons mission doesn't go as planned, researchers will miss their best chance to study Pluto during this lifetime—the planet is now headed toward the farthest-away stretch of its 248-year elliptical orbit around the sun. The spacecraft must endure a barrage of prelaunch tests. Here, the probe sits in its "test yoke" during the mass-properties test, conducted to determine how mass is distributed throughout the craft and to help mission engineers find its center of gravity. The tanks in the foreground supply nitrogen to the air bearings in the mass-properties machine so that the craft literally floats on a cushion of nitrogen.
Keeping the Craft in Line
Yanping Guo, leader of the New Horizons Mission Design Team, stands in front of the 60-foot dish antenna at the Johns Hopkins Applied Physics Laboratory's Satellite Communications Facility. After launch, Guo and her team, who designed the probe's path to Pluto, will work with the mission operations and navigation teams to keep New Horizons on track.
Dishing Up the Data
New Horizons will use a "dish stack" of three antennas to transmit information between Earth and its deep-space destination. The most powerful of the three—the high-gain antenna—forms the base of the stack, with a large dish that covers nearly a full side of the probe. The medium-gain antenna, which uses a much smaller dish, rests directly above the high-gain antenna, and the low-gain antenna sits at the top. During testing, the spacecraft team used the gold squares seen on the dish surfaces to align the craft and ensure that it was facing the correct direction.