The ruling by the world's top astronomers to boot Pluto from the planet category is sending shock waves through another set of dedicated stargazers: the world of astrologers, who are already mulling how this turn of events will affect our moods, our lucky numbers and our chances of getting a date on Saturday night.

For weeks, astrologers have been buzzing about the proposal approved yesterday at the International Astronomical Union general assembly in Prague that will recast the map of the solar system for the first time since 1930. After days of impassioned debate, the astronomers voted to demote Pluto, the smallest of the nine planets, to a new class of solar-system bodies called dwarf planets.

Astrologers believe that the positions of the moon, sun and stars affect human affairs and that people born under the 12 signs of the Zodiac tend to pick up qualities of the planets associated with those signs. Some astrologers, including leaders of the American Federation of Astrologers and the Astrological Association of Great Britain, are standing firmly by Pluto. They say they will continue to regard the icy orb as a full-blown planet with a powerful pull on our psyche, despite the astronomers' decision.

"Whether he's a planet, an asteroid, or a radioactive matzo ball, Pluto has proven himself worthy of a permanent place in all horoscopes," says Shelley Ackerman, columnist for the spirituality Web site Beliefnet.com. Ms. Ackerman criticized the IAU for not including astrologers in its decision.

Others warned that Scorpios -- people born between Oct. 23 and Nov. 21 -- should be especially cautious in the coming days because the sign is closely associated with Pluto.

"Scorpios can be extremely explosive, and very direct, and this could be the trigger that makes them explode," says Milton Black, an Australian astrologer who claims to have more than 580,000 clients. Laura Bush, Hillary Clinton and Condoleezza Rice, take note. All three are Scorpios.

Yesterday's ruling in Prague brought good news to some. The astronomers indicated that several planet-like bodies -- including the asteroid Ceres and the newly discovered UB313, sometimes known as Xena -- will also be classified as dwarf planets. That has generated excitement among a small group of practitioners known as "minor-planet astrologers" who have long contended that outer-lying asteroids and ice balls exert a powerful tug on our psychological makeup. Some astrologers believe that officially introducing new dwarf planets to the charts might give astrologers additional information about people, by providing more planetary bodies and forces to study in the charts.

"This is a moment that I've been waiting for a long time," says Eric Francis, a minor-planet astrologer who edits the Web site Planetwaves.net. "People are finally talking about Charon." Charon is Pluto's largest moon, which astronomers briefly considered granting official planet status at the IAU meeting.

Mr. Francis and many other minor-planet enthusiasts are interested in raising awareness about Charon and the new dwarf planets, Ceres and UB313, in part because they consider them female planets that would symbolize a rush of new maternal energy into the cosmos.

"Most of our clients are women, and we need stories women can relate to," says Mr. Francis. (A planet's sex is determined largely by the name given to it by astronomers.)

StarIQ.com astrologer Michael Wolfstar suggests that the asteroid Ceres is a humanitarian, compassionate force "associated with relief operations, the food industry, and parent-child relationships." According to the site, she is currently pushing for "the return of refugees to southern Lebanon" and "reforms in the organic-milk industry."

Even before the vote, some astrology Web sites were welcoming the potential new arrivals to the planetary fold and buzzing about how they might affect current world events, including the future of JonBenet Ramsey murder suspect John Mark Karr. "As Ceres goes on to oppose realistic Saturn, the astrologer might reasonably expect that the DNA evidence won't match," wrote Mr. Wolfstar earlier this week.

Mr. Wolfstar says Ceres's association with the parent-child relationship connects her to the Ramsey case. At the time of Mr. Karr's arrest, Ceres was opposing Neptune, a planet involved with imagination and fantasy. Mr. Wolfstar says that opposition may imply that the confession wasn't reliable.

The IAU decision had less impact on some older branches of astrology that already ignore the influence of more recently discovered planets, such as Uranus (discovered in 1781) and Neptune (discovered in 1846). In the Indian tradition of Vedic astrology, for example, astrologers generally use only the first five planets. A small group of classical astrologers in the West use only the first seven. Modern astrologers, who account for an estimated 90% of American practitioners, have long worked with a nine-planet system.

This is also not the first time a new discovery has rocked the astrology world. In 1977, astronomer Charles Kowal discovered Chiron, a comet located between Saturn and Uranus. Some astrologers welcomed Chiron into the planetary fold, and many still use it today.

Companies that make chart-reading software for astrologers currently are adjusting their products to include more information on dwarf planets. Astrolabe, an astrology software company in Brewster, Mass., released a software patch this week for users that provides additional information on the asteroid Ceres.

"As soon as the orbital elements are released, we can incorporate new asteroids into the software," says Madalyn Hillis-Dineen, marketing director for the company. But, she adds, the company isn't about to turn its back on Pluto.

Horoscope columnists are wrestling with whether to incorporate the new crop of dwarf planets into their chart readings. Michael Lutin, columnist for Vanity Fair, says he will consider the newcomers. But he notes that they aren't likely to have massive impact on our personal lives because of their location at the outer reaches of the solar system: "UB313 is never going to tell you whether Wednesday is good for romance."