NASA says its giant white balloon is "performing beautifully" following its successful launch after five failed attempts last year.
NASA scientists launched their 'super-pressure' balloon on Sunday from Wānaka Airport, carrying a special telescope to image large galaxy clusters.
NASA balloon program office chief Debora Fairbrother told AM the last successful launch was in 2017.
"This has been huge that we've been able to launch yesterday and the balloon is performing beautifully."
And while the ballon looked "saggy" during its launch on Sunday, Fairbrother says it will inflate to the size of a rugby stadium when the sun is out.
"What happens is it contracted a little when the sun went away and the gases cool, but it didn't come down very far. When it comes out with the sun it will be fully inflated again."
And while the launch was successful, the road to get there took "a lot of work".
Airway NZ traffic services general manager Katie Wilkinson said many teams worked together to create an airspace that is suitable for the balloon.
"To get [the balloon] all the way up to 60,000 feet which is basically the top of our controlled airspace."
Wilkinson said air passenger traffic around the balloon is "controlled" and the restricted airspace around the balloon is followed wherever it ends up.
Fairbrother told AM NASA is hoping the balloon will stay above us for "many many months".
"Basically we will be tracking it, we will have predicted winds so we'll have predictions on where it will go."
She said anytime the balloon crosses land or crosses a new continent, NASA will make an assessment of the balloon's health.
"Our desire is for us to fly for many months."
Watch Fairbrother and Wilkinson's interview above.
