NASA planned to try again Wednesday to launch the New Horizons probe, although the forecast held a greater chance of thunderstorms, clouds and gusty winds that could prevent a launch, reports CBS News' Peter King.
On Tuesday, winds at the launch pad exceeded the space agency's 38 mph flight restriction.
"The winds picked up sooner than expected," said MIT scientist Richard Binzel, one of the mission's investigators. "Blame the meteorologists."
A successful journey to Pluto would complete an exploration of the planets started by NASA in the early 1960s with unmanned missions to observe Mars, Mercury and Venus.
"What we know about Pluto today could fit on the back of a postage stamp," Colleen Hartman, a deputy associate administrator at NASA, said earlier. "The textbooks will be rewritten after this mission is completed."
CBS News space consultant Bill Harwood said that until this mission the best information about Pluto came from the Hubble Telescope, which provided only out-of-focus images of a white globe. This mission will provide pictures as sharp as the ones available of the moon.
The launch also drew attention from opponents of nuclear power because the spacecraft is powered by 24 pounds of plutonium, whose natural radioactive decay will generate electricity for the probe's instruments.
Pluto is the only planet discovered by a U.S. citizen, though some astronomers dispute Pluto's right to be called a planet. It is an oddball icy dwarf unlike the rocky planets of Mercury, Venus, Earth and Mars and the gaseous planets of Jupiter, Saturn, Uranus and Neptune.
"My dad would be absolutely thrilled to see this," said Annette Tombaugh-Sitze, whose father, astronomer Clyde Tombaugh, discovered Pluto in 1930.
Pluto is the brightest body in a zone of the solar system known as the Kuiper Belt, made up of thousands of icy, rocky objects, including tiny planets whose development was stunted by unknown causes. Scientists believe studying those "planetary embryos" can help them understand how planets were formed.
"Something, and we don't understand what ... stopped that process of growth and left us with this fantastic relic, this forensic evidence of planets that were arrested in the midstage of growth," said Alan Stern, the $700 million mission's principal investigator.