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The US space agency, Nasa, has been forced to postpone the launch of its New Horizons mission to Pluto.
The launch site was experiencing gusting winds that had several times exceeded safe limits.
The spacecraft is now scheduled to lift off from Cape Canaveral, Florida, on Wednesday at 1316 EST (1816 GMT).
The probe was originally due to launch at 1824 GMT, but Nasa pushed back the launch seven times before finally deciding to scrub Tuesday's attempt.
Controllers kept postponing the launch time until running up against the end of Tuesday's launch window at 2023 GMT.
However, the high winds at Cape Canaveral Air Force Station refused to subside and Nasa had to call a halt to the countdown.
The failure of a "fill and drain" valve in the Atlas 5 heavy-lift rocket also contributed to an initial delay. However, it later started working properly.
Nasa has until February 14 to launch the probe. But if it fails to lift off before 3 February, up to five years could be added on to the flight time to Pluto - increasing the chances of a mission failure.
The $700m probe will gather information on Pluto and its moons before - it is hoped - pressing on to explore other objects in the outer Solar System.
Last planet
The agency's administrator Dr Mike Griffin commented: "With this mission we set out on the initial reconnaissance of the last planet known to exist in the Solar System at the time we started the space age.
"We've since discovered other large objects out there and there's some argument over whether Pluto is really a planet at all, and if it is, is it the last planet."
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Some astronomers believe Pluto is not a true planet
Some astronomers say Pluto is not a true planet at all, and should be classed instead alongside the small, icy objects which make up the region of space known as the Kuiper Belt.
This region, which lies beyond Neptune, consists of perhaps tens of thousands of icy objects spread out between 30 and 50 times the distance between the Earth and the Sun.
Pluto is thought by some to form a "double planet" with its companion Charon.
Dr Alan Stern, the mission's principal investigator said: "I think we're going to learn a great deal with how the solar system formed, about the bombardment history of the Solar System, about how double planets work, about how rapidly escaping atmospheres work.
"There's so many presents inside the bag that I don't know where we're going to begin."
Slingshot manoeuvre
If Nasa launches New Horizons before 3 February, the probe will be in position to swing by Jupiter, using the planet's gravity to pick up speed in a slingshot manoeuvre.
This will boost the probe's speed away from the Sun by nearly 4km/s, slashing the flight time to Pluto - and reducing the chances of a mission failure.
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New Horizons could get to Pluto by the year 2015
That boost will allow New Horizons to reach Pluto in July 2015. Otherwise, the journey will take until 2018 at the earliest.
New Horizons will fly by Pluto and its largest moon Charon on the same day. The spacecraft's seven instruments will carry out detailed mapping of Pluto's surface features, composition and atmosphere.
After the Pluto encounter, it is up to Nasa to decide whether to grant the spacecraft an extended mission. Should this happen, mission scientists plan to send New Horizons to visit two Kuiper Belt Objects (KBOs) with diameters of 50km (30 miles) or more.
Scientists believe they can learn about the evolution of the Solar System by studying the Kuiper Belt since it possesses debris left over form its formation.
Anti-nuclear activists have staged small protests about the spacecraft's 33kg payload of plutonium fuel.
Nasa said there was a 1 in 350 chance of a mishap that released plutonium around the launch site. Even so, it said, the chance of dangerous radiation exposure to workers and the public was low.
