The US space agency is geared up to send Orbital Science Corporation's Antares rocket and Cygnus cargo spacecraft to the International Space Station (ISS).
Mission managers have given the 'go' for a 6.45 p.m. (EDT) Monday launch from NASA's Wallops Flight Facility in Virginia.
The third commercial re-supply flight by a Cygnus spacecraft to the ISS will transport some 5,000 pounds of supplies and experiments to the orbiting laboratory.
There is a 98% chance of favourable weather at the time of launch, NASA said in a statement.
Earlier, SpaceX's Dragon spacecraft splashed down into the Pacific Ocean, bringing back to the Earth hundreds of pounds of cargo and the results of critical, long-term research from the ISS.
The returned cargo could aid in the development of more efficient solar cells and semiconductor-based electronics, the development of plants better suited for space and improvements in sustainable agriculture.
"This mission enabled research critical to achieving NASA's goal of long-duration human spaceflight in deep space," said Sam Scimemi, director of the ISS division at the NASA headquarters in Washington, DC.