Nasa staff had all their fingers and toes crossed as they hoped for eighth time lucky for their balloon launch at Wanaka airport this morning.

The airport was closed in preparation for the launch, which was finally successful after multiple false starts.

The lift-off of the super pressure balloon has been deferred seven times in the past two weeks but was launched just after 10am on a clear day in Wanaka with light winds.

The agency wants to test the technology for long-duration flights at mid-latitudes, as long-haul balloon flights become a cheaper tool for the study of the near-space environment.

The balloon was taken out of its box at about 8am, with inflation taking about two hours.

Just before 10am, a smaller tow balloon that had been holding the main balloon off the ground was deliberately detached, and the main balloon was launched about an hour later.

Wanaka Airport spokesperson Caroline Dumas said the balloon had a small piece of cargo on board – an Anzac poppy.

The same thing was done last year when Nasa launched its first balloon from the airport.

“We thought it was something nice,” Ms Dumas said.

“It’s especially poignant this year because it’s Anzac Day.”

Local residents and visitors were able to watch the balloon as it began its journey, from vantage points around Wanaka.

The ballloon will be in the air for 100 days.

The volume of the balloon is more than half a million cubic metres, and it will float 34km above the earth.