Juno probe heads for Jupiter from Cape Canaveral

The Atlas 5 rocket launched from Cape Canaveral Air Force Station after a brief delay caused by a helium leak

A $1.1bn (£0.7bn) unmanned Nasa space mission has launched from Florida on a journey to the planet Jupiter.

The Juno spacecraft will cruise beyond Mars to put itself in orbit around the gas giant in 2016. It is the first solar-powered mission to venture this far from the Sun.

The mission launched atop an Atlas 5 rocket from the Cape Canaveral Air Force Station on Friday at 12:25 local time (16:25 GMT; 17:25 BST), after a brief delay caused by a helium leak.

There were concerns with the helium charging system on the rocket's Centaur upper stage, but a small leak on the "ground side" of the rocket was found to be the culprit.  “Today, with the launch of the Juno spacecraft, Nasa began a journey to yet another new frontier," said the agency's administrator Charles Bolden.

"The future of exploration includes cutting-edge science like this to help us better understand our Solar System and an ever-increasing array of challenging destinations."

Storms could spoil shuttle Atlantis launch

The countdown to Friday's final launch of a space shuttle has begun at the Kennedy Space Center (KSC).

But the famous clock in front of the spaceport's press centre may struggle to get all the way down to zero.

Forecasters say showers and even storms will be over Florida's Space Coast by the week's end.  When it does fly, the Atlantis orbiter will be hauling more than 3.5 tonnes (8,000lb) of supplies to the International Space Station (ISS).   "I wish I had a better briefing for you," Nasa's shuttle weather officer Kathy Winters told reporters.   Right now we are going with a 60% chance of KSC weather prohibiting launch due to the potential for showers and isolated thunderstorms in the area."

Huge crowds are expected on the Space Coast to watch the 1126 local time (1526 GMT) lift-off. 
The forecast is going to make for some tough decisions on their part. Do they endure the jammed roads and long queues on Friday to get into the best viewing positions, only for the launch to be postponed? Or do they stay away, hoping for a 24-hour delay and much better weather prospects.
Saturday's forecast is better (40% chance of no-go weather conditions); Sunday's even more so (30%)
Winters said early morning conditions on Friday might be fine, but those showers and storms were likely to pop up just around launch time