Rocket Lab will carry four satellites during its second test launch, some time after the next vehicle is taken to Mahia Peninsula next month.
The company says its Electron orbital launch vehicle will carry two Earth-imaging Dove satellites for Planet and two Lemur-2 satellites from Spire for weather mapping and ship traffic tracking.
The flight is the second of three in Rocket Lab's Electron test program and follows the
inaugural Electron test flight carried out in May which made it to space but not into orbit.
Founder and chief executive of Rocket Lab, Peter Beck said carrying a test payload marked a significant milestone for the Electron programme, enabling Rocket Lab to gather crucial data and test systems for the deployment stage of a mission.
He said he was ''thrilled'' with Electron's performance in the first test flight on May 25 and was eager to test the next crucial step - payload deployment of the four satellites which are each smaller than a shoebox.
''No major changes to the launch vehicle hardware have been required, the third-party error that meant we didn't make orbit has been corrected and we're focusing
on the six Electron vehicles in production right now."
The Electron vehicle for the "Still Testing" flight is expected to be trucked to Rocket Lab's Launch Complex 1 on the peninsula next month with a launch window to open in
the weeks following once vehicle checks are complete.
''While we're still very much operating in a test phase and can likely expect a few scrubs during the second test flight attempt, we're incredibly excited about carrying Planet and Spire payloads on Electron.''
The data these companies gather has an increasingly significant role to play in how we understand our planet and better manage it," said Beck.
Mike Safyan, senior director of launch at Planet, said his company was ''excited to quite literally be riding the leading edge with Rocket Lab".
Planet has a network of 190 satellites that it says collects more imagery daily than any other commercial provider.
Spire, the world's first commercial weather satellite constellation, covers every location on earth over 100 times per day. The multi-sensor satellites gather global atmospheric measurements for advanced weather warnings and predictions and track global ship traffic.