President Donald Trump has officially launched a new military service, the US Space Force.
The Pentagon force is focused on warfare in space.
The service, the first in more than 70 years, falls under the US Air Force.
At an army base near Washington, President Trump described space as “the world’s newest war-fighting domain”.
He said: “Amid grave threats to our national security, American superiority in space is absolutely vital.
“We’re leading, but we’re not leading by enough, but very shortly we’ll be leading by a lot.”
“The Space Force will help us deter aggression and control the ultimate high ground,” President Trump added.
The funding allocation for the new service was confirmed on December 20 when President Trump signed the $738 billion annual military budget.
The launch of the Space Force will be funded by an initial $40 million for its first year.
Space Force is not intended to put troops into orbit, but will protect US assets – such as the hundreds of satellites used for communication and surveillance.
The new military service comes as US military chiefs see China and Russia making advancements in the military final frontier.
VP Mike Pence previously said the two nations had airborne lasers and anti-satellite missiles that the US needed to counter.
Space Force will build on the work of the existing US Space Command (SpaceCom), which was created in August to handle the US military’s space operations.
Air Force Secretary Barbara Barrett said the Space Force would comprise around 16,000 Air Force and civilian personnel.
It will be led by Air Force General Jay Raymond, who currently runs SpaceCom.