Is there a 6th Military branch?

I heard a rumour about a 6th branch of the military. Some say it’s the Coast Guard, others say it’s the Space Force. Does anybody have concrete information on this?

Yes, there is indeed a sixth branch of the U.S. Military—it's the United States Space Force. The Space Force was established on December 20, 2019, under the Trump administration.

The current branches of the U.S. Military, in order of their establishment, are:

1. Army (1775)

2. Navy (1775)

3. Marine Corps (1775)

4. Coast Guard (1790- though it has changed names several times)

5. Air Force (1947)

6. Space Force (2019)

The duties of the U.S. Space Force include organizing, training, and equipping personnel to protect the U.S. and allied interests in space. This involves activities like monitoring ballistic missile launches, tracking space debris, and maintaining satellites that facilitate communication for other military branches. Despite its sci-fi sounding name, the Space Force doesn't put soldiers in space (as of now). Instead, it's concerned with the critically important and increasingly contested environment of space relative to national security.

Finally, it's worth noting that the Coast Guard is a unique entity. During peacetime, the Coast Guard operates under the Department of Homeland Security. However, in times of war or at the direction of the President, the Coast Guard operates as a service in the Department of the Navy. Hence, it is indeed considered one of the branches of the U.S. military.