Staff have started arriving in Wanaka to prepare for the launch after Easter’s Warbirds Over Wanaka airshow.
The test programme is aimed at achieving flights of more than 100 days at ‘‘float altitudes’’ of about 33km.
The balloon launched from Wanaka in 2016 survived for 46 days, 20 hours, and 19 minutes. The record for a Nasa balloon remaining at altitude is 54 days.
Nasa was continuing to perfect the technology, spokesman Jeremy Eggers said yesterday.
Improvements had also been made to the ‘‘launch collar’’ electronics that held the balloon fabric together during launch operations.
The balloons are 532,000cum in volume when fully inflated, which is about the size of Forsyth Barr stadium, in Dunedin.
Nasa launched balloons from Wanaka in 2015, 2016, and 2017, but its planned 2019 launch from Wanaka was cancelled due to a United States Government ‘‘partial shutdown’’.
Balloon programme office chief Debbie Fairbrother said this year’s mission was critical to validating and certifying the super pressure balloon as an ‘‘operational flight vehicle’’.
Nasa has plans for another test flight from Wanaka in 2021 before a balloon is used to launch the Galactic/Extragalactic ULDB Spectroscopic Terahertz Observatory (Gusto) mission from the Antarctic.
Mr Eggers said Gusto was a $40million mission to measure emissions from the interstellar medium — the cosmic material found between stars.
