posted August 16, 2006 12:52 PM              

Nine no longer: Panel declares 12 planets
By Gareth Cook, Globe Staff | August 16, 2006

The solar system has 12 planets.

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Sign up for: Globe Headlines e-mail | Breaking News Alerts That is the conclusion, to be announced today, of an international panel formed to devise a scientific definition of a planet and settle an increasingly intense dispute over whether Pluto qualifies. The panel suggests retaining Pluto and immediately adding three new planets to the nine that are familiar to any schoolchild: Ceres, currently considered a large asteroid; Charon, now considered a moon of Pluto; and Xena, a recently discovered object that is larger than Pluto.

But the group's proposal also makes clear that many more objects in the solar system -- perhaps dozens of them -- could qualify as planets after further study.

The new definition has been approved by the executive committee of the International Astronomical Union , and a vote of the union's general assembly is scheduled for Aug. 24 at a conference underway in Prague. If it is approved, which several astronomers said seems likely, the world's textbooks and museum displays would have to be updated -- not to mention solar system models, posters, software, and toys with only nine planets.

The change, scientists say, would be a mark of the great age of discovery that astronomy has entered over the last three decades, with the advent of space probes, powerful telescopes, and new observational techniques.

GLOBE GRAPHIC: A new solar system YOUR VIEW: How will you remember the names of the planets?
YOUR VIEW: What would you name the new planets?

The current model of the solar system has held since 1930, when Pluto was discovered. Since then, astronomers have discovered that the solar system is a much larger, more diverse place. These discoveries, especially the findings that Pluto is markedly different from the other planets and is part of a vast cloud of frozen worlds known as the Kuiper Belt, have challenged the neat categories in the nine-planet solar system. Faced with these problems, the Astronomical Union has been struggling for years to work out its first formal definition of a planet.

``It is wonderful when new scientific discoveries present you with new problems," said Richard Binzel , a Massachusetts Institute of Technology professor of planetary geology who served on the panel. ``This is almost the essence of being a scientist."

The proposal defines a planet as an object that circles the sun and is massive enough that its own gravitational forces compress it into a roughly spherical shape. Depending on its composition, a planet would have to be at least roughly 250 to 500 miles in diameter to qualify. It designates a new subcategory of planet, the ``pluton," a Pluto-like planet that takes at least 200 years to circle the sun. Pluto, Charon, and Xena are all plutons, and scientists expect many more to be discovered. Under the proposal, Ceres is an ordinary planet.

Moons are excluded from planetary status, using a criterion that depends on the relative mass of two bodies that are gravitationally tied. If one body is much smaller than the other, then it is considered a moon. Pluto and Charon are closer in mass, and so they are dubbed a double planet. The Earth's moon is round and much larger than Pluto, but it is so much smaller than Earth that it is considered a moon, not a planet.Continued...

posted August 16, 2006 01:20 PM            

...now that Pluto is a "Pluton", a subcategory of planet (subplanet), does Scorpio no longer have a home?

posted August 16, 2006 01:29 PM            

I always felt uneasy about not including Ceres as one of the planets used in Astrology.

It is a large round object which is unlike all the other asteroids in the main asteroid belt. It's not much smaller than Pluto. It is like 1/3 Pluto's size,and it is much closer to us than Pluto. It doesn't have a highly eccentric orbit like Pluto does. It pretty much has a stable orbit. Astronomers have argued that Pluto is not a planet. If that's a case, Pluto is no more Planet than Ceres. Ceres was also first classifed as a planet until they found numerous asteroids and pretty much have Ceres as the leader of the pack.

posted August 16, 2006 09:58 PM              

My Ceres is in Aquarius and so I forget to eat properly doing other things. My solution is to follow diets setup by other people into nutrition.

There is something earthy about Ceres but I'm not sure if I feel it's all Virgo.
Maybe a touch of Scorpio.

In any case it's big news. As for Pluto, I never really got Pluto as much as Mars, which seems to describe Scorpios better for me.

Natasha

posted August 16, 2006 10:22 PM              

What a "Charlie Foxtrot"! In lay terms that means cluster f***.

When I had my chart made it didn't include Ceres, Charon or some of the other prominant astroids that some folks have on their charts.

I have to wonder how long some of these bodies have been studied by astrologers. I know with Xena it will take time to determine its effects, orbit time... Does the astrology world take its cues from the astronamy world?

posted August 17, 2006 12:01 AM            

Diameter- 1256 km (751 miles) (Pluto is roughly twice this, at 2370 km or 1422 miles)
Distance from Pluto- 19,700 km (11,820 miles)
Orbital period around Pluto- 6.38718 Earth Days

posted August 17, 2006 01:51 AM            

Chiron is of the centaur class that orbits between Saturn and Uranus, and it's named after the wise mentor of gods and heroes

posted August 17, 2006 02:01 PM              

As for Ceres being deemed a planet in astrology, I'm sort of mixed. In my chart, it sits inbetween my 10H Sun-Mercury conjunction in Gemini, whih would make that a stellium.

I wouldn't object to astrology introducing a class of "minor" planets that would include bodies like Ceres, UB313 and Chiron (although I think Pluto-Charon should be consider a major planet) - planets that are significant in the charts but play more of a supporting role to the major planets. However, I doubt this will evolve. Either way, I'm sure there'll be a lot of debating.

posted August 17, 2006 03:07 PM            

There are more bodies that are larger than Ceres besides Pluto and 2003 UB313

Kuiper Belt objects:
Ixion
Quaoar
Orcus
2003EL61
2005FY9

posted August 19, 2006 06:49 PM              

I love it when no one cares about astronomy until there is a war or something for us to need a distraction from. As if on some level we are supposed to believe that "not all is as it seems" -- an assertion of us being nothing but a bunch of pion atoms running around caustically.

It's not any of these astronomical challenges which has my full attention, but rather, why I'm suddenly being told to look out into space to question all that was once known ...

... I don't buy it ...

posted August 19, 2006 07:19 PM            

by Frederique Pris 1 hour, 33 minutes ago

PARIS (AFP) - Star signs and astrology charts -- relied on by millions as a key to divining the future -- would not be much affected if three new planets are added to the solar system, experts said.

Leading astronomers meeting in Prague are planning next week to add three new planets to the nine known to children around the world: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.

The International Astronomical Union (IAU) is proposing a new definition of the word "planet" to take into account recent scientific discoveries, notably of asteroids larger than distant Pluto, the smallest of the nine.

This would result in three new "pluton" planets being created: Pluto's moon Charon; the asteroid Ceres; and the so-called "object 2003 UB313", which was discovered in 2003 by an American astronomer and is unofficially called "Xena".

Sylvain Pech, an astrologer from the French city of Marseille, said the discovery of Xena "opens a door" since it is situated outside the orbit of Pluto, until now seen as "the deepest level of our collective psyche."

"It has got astrologers interested... but first we need to work out the meaning of its place within the solar system."

But he said the addition of the other two objects -- Charon and Ceres -- was of no special interest, the first forming part of Pluto's planetary system, and Ceres having been known to astronomers for a long time.

Adding three planets to the solar system "wouldn't change anything to the way I work," agreed Christine Haas, an astrologer for French radio station RTL and several French magazines.

She described astrology as a "very ancient method based on observations made again and again over thousands of years, using laws of analogy and correspondences."

In antiquity, she said, astronomers -- who were also astrologers -- observed parallels between what they saw taking place in the skies and on Earth.

"When Mars moved in front of the constellation of Aries, they observed an increase in aggressivity and conflicts," she said.

Pech explained how astrology maps correlations between the different parts of a human being and those of the solar system.

For instance the moon, Earth's closest satellite, is traditionally associated with the first moments of a person's life and as such is linked to impulsive behaviour.

Saturn, the furthest planet visible to the naked eye, is associated with ageing and death.

The planets located on the outer rim of the solar system -- Uranus, discovered in 1781, Neptune (1846) and Pluto (1930) -- are associated with the collective psyche, rather than the individual, Pech explained.

For Christine Haas, "we can even function without Uranus, Neptune and Pluto" -- the three most recent discoveries in the solar system.

Fundamentally, she said, "astrology is not a science but an art of interpretation".