Nasa has postponed the launch of its data-gathering balloon from Wanaka because of the weather.
Scientists had worked on the super pressure balloon all night in preparation for lift-off at 8am today.
However, the US space agency said wind conditions at ground level and at 250m weren't right for the balloon to be laid out properly.
"We knew going into today's attempt that the winds were marginal, and unfortunately, they just didn't set up for us in a way that would support launching," Nasa balloon programme office chief Debbie Fairbrother said.
Balloon campaign manager Dwayne Orr, of Nasa's Columbia Scientific Balloon Facility, said it was "the nature of the business".
"It's not uncommon to wait weeks for weather conditions to set up in a way favourable for balloon operations. We're a patient bunch; we're prepared to wait out the weather at least through the end of April and potentially longer if we need to."
Nasa said it would decide by 2pm today whether or not to try again tomorrow morning.
The balloon is set to be in the air for about 100 days before falling back to earth in South America.