Cheers of joy could be heard across the tarmac at Wanaka Airport yesterday morning as Nasa's stadium sized balloon left Earth on a possible 100-day journey around the southern hemisphere.
After a month of early mornings and seven failed launches, there was a sense of relief among the Nasa super pressure balloon team based at the airport, but their work is not done yet.
Nasa's balloon programme office chief Debbie Fairbrother said the test now began with the balloon ascending to about 109,000 feet (33.5km) and hopefully staying up for 100 days.
About 11pm, the balloon was about 40km east of Christchurch and heading in a northeasterly direction.
Despite a few minor technical ''hiccups'', the launch was a success, Ms Fairbrother.
She said she was not sure when the balloon team would be back in Wanaka, but they would eventually return having made a 10-year commitment to the airport.
''If I had my choice, we would be coming back here next year.''
Nasa has also constructed a purpose-built balloon launch pad on the northeast side of the airport.
In commemoration of Anzac Day, a poppy was attached to the balloon's payload.
The balloon will now head along the east coast of the South Island before floating off towards South America.
Some of the balloon team had been in Wanaka since early February and were looking forward to heading home, Ms Fairbrother said.
''We were pretty excited with the launch ... We were waiting a little bit this time; not as long as last year but we were ready for a launch.''
Last year's launch did not take place until May 18.
Today's launch was the third from the airport.
Previous flights lasted 32 days in 2015 and 46 days in 2016. The record for a Nasa super pressure balloon flight is 54 days.
Data collected from those missions was used to fine-tune the balloon and technology used in this year's mission.
The primary focus of this mission was to again test the super pressure balloon technology on a long flight.
Attached to the balloon is the University of Chicago's Extreme Universe Space Observatory (Euso telescope), which is about the size as a small car.
The Euso telescope is designed to detect high-energy cosmic rays, which originate outside of our galaxy and penetrate Earth's atmosphere.
Colorado School of Mines deputy principal investigator and Euso telescope project manager Lawrence Wiencke said it was the first time the cosmic rays had been observed in such a way.
''We going to look for streaks of light these particles make when they enter the atmosphere ... We want to find out where these particles are coming from. It's very, very exciting.''
If successful, the telescope would be installed on the international space station as part of a planned mission, Prof Wiencke said.
Nasa's balloon experts at its Columbia Scientific Balloon Facility and Wallops Flight Facility in Virginia will control balloon flight operations throughout the mission.
When the mission had run its course, a parachute on the Euso would deploy, bringing it back to Earth in one piece, while the balloon would freefall.
There were a number of countries where the balloon could land but its final destination had not yet been decided.
Previous balloons have come down in Australia and Peru.
The balloon's progress can be tracked at www.csbf.nasa.gov/newzealand/wanaka.htm.