Nasa Columbia Scientific Balloon Facility meteorologist Chris Schwantes said, ``we intentionally picked March 25th as our first available date as it could be the earliest time the stratospheric winds are set up and we wanted to make sure we could take advantage of them.''
``It could be close, there could be a delay of a few days, but we need the stratospheric winds so we can get that kind of nice orbit around the southern atmosphere,'' he said.
This year's launch will be the third time Nasa has used Wanaka airport as one of its global launch sites for its pressure balloons.
In 2016, four attempts to launch the balloon had to be cancelled due to bad weather.
Mr Schwantes said on launch day he had to inflate a meteorological pilot balloon, release it every 30 minutes and calculate wind speed and direction at different altitudes up to 1300m using a theodolite instrument.
``It's one of the more critical weather measurements and data that we have on launch mornings to tell us whether it's going to be a good day or a bad day and whether we feel comfortable to launch or not,'' he said.
The long duration balloon flights at constant altitudes provide Nasa with inexpensive access to the near space environment.
This year, the super pressure balloon will be flying the University of Chicago's Extreme Universe Space Observatory (EUSO-SPB) payload and will lift off from its own launch pad on the northeast side of the airport.
A Nasa spokesman said Mr Schwantes, scientists involved in the EUSO-SPB and other Nasa personnel would be available for questions and answers at the Nasa and the Wanaka Airport ``Locals Day'' outreach event this Thursday between 4pm and 6pm.
