The first space mission to Pluto has blasted off after numerous delays caused by high winds at Cape Canaveral.
The mission had to be launched this year to reach Pluto before its elliptical orbit takes it so far away from the sun that its atmosphere freezes.
"What we know about Pluto could be written on the back of a postage stamp, but after this mission we'll be able to fill textbooks with new information."
New Horizons will dive through the atmosphere of Jupiter in 2007 to pick up a huge gravitational increase in speed, becoming the fastest manmade object ever when it reaches 36,000 miles per hour.
This gravitational assist idea was first suggested by UK science fiction author Arthur C Clarke.
"This is the gateway to a long, exciting journey," said Glen Fountain, New Horizons project manager at the Johns Hopkins University Applied Physics Laboratory.
"The team has worked hard for the past four years to get the spacecraft ready for the voyage to Pluto, and beyond to places we've never seen up close.
Once past Pluto the craft will continue sending data as it explores the Kuiper Belt, the region of ancient, icy, rocky bodies beyond Neptune that contains the 1,000 kilometre planetary object XR190, provisionally named Buffy.
After around 30 years at its expected speed the probe will also become the furthest manmade object from earth as it breaks the record set by Voyager One.
Dubbed Barnard's star B, newly discovered planet is believed to be rocky
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