Nasa's planned super pressure balloon launch from Wanaka Airport has been cancelled for today.
Balloon programme office chief Deborah Fairbrother said the launch, which had been scheduled for 10am, was cancelled due to winds.
"Unfortunately the wind was higher than 6 knots and coming in from a cross direction."
The call to cancel was made at 9am. A meeting will be held around midday to assess the situation for a launch for tomorrow.
If the launch does go ahead tomorrow, locals have been encouraged to not visit the airport for the launch.
Optimal locations for safe viewing can be found on the Wanaka Airport's social media channels.
In order to launch safely the maximum wind speed needs to be below 5 knots.
Earlier, a weather window opened above Wanaka, which gave hope the launch would go ahead.
The United States space agency has spent several weeks preparing to send a 2.3-tonne stadium-sized balloon on a long-duration test flight around the southern hemisphere.
Ms Fairbrother said the team of 25 staff and contractors had done an amazing job to overcome some ‘‘massive logistical challenges’’ to get ready for launch.
Nasa first began launching super pressure balloons from Wanaka in 2015. This would be the fourth launch.
The programme was temporarily halted due to funding and Covid-19 issues.
Ms Fairbrother said light, reliable winds were needed at both the surface low levels up to about 300m.
Winds flowing in opposite directions on the ground and lower levels could have a shearing effect on the balloon.
Favourable stratospheric wind conditions were also needed at 33.5km above the ground, where the balloon would float.
If more launch attempts were needed, they would be announced by 2pm the day before, depending on weather forecasts.
The primary goal of the flight was to validate and certify the balloon technology and, in particular, the balloon’s capability to pressurise at high altitudes and cope with heating and cooling during the day-night cycle, Ms Fairbrother said.
Meanwhile, the Wanaka branch of the Royal Society is hosting a public lecture on the scientific balloon programme at the Wanaka Presbyterian Church hall at 6pm on Friday.
