SpaceX, led by entrepreneur Elon Musk, is set to attempt the maiden launch of Starship, the most powerful rocket ever developed.
Standing nearly 120 meters (393 feet) tall, the rocket boasts almost double the thrust of any in history.
Uncrewed, the demonstration will lift off from Boca Chica, Texas, with the goal of sending the upper-stage vehicle around the globe.
Musk has cautioned that initial rocket launches often experience failures, so expectations should be tempered.
Starship aims to revolutionise the rocket industry with its fully and rapidly reusable design, facilitating frequent flights to orbit for people and satellites.
The launch will be the first time the top segment of Starship is tested with its lower stage, called Super Heavy.
If successful, the project could lead to interplanetary travel for ordinary humans.