SpaceX, NASA and military personnel will gather in various control rooms across the country to support this mission.

But it all starts here — in Firing Room 4 at Kennedy Space Center.

It's located about three miles west of the launch pad, and the launch controllers that gather here are tasked with ensuring that the rocket and ground equipment are healthy for takeoff.

Today, Firing Room 4 is decorated with a giant "X" logo, for SpaceX, but when it was built in the 1960s — it was actually just a massive conference room. It was later converted into a "firing room," or launch control center, to support Space Shuttle missions.

After the SpaceX rocket takes off, Firing Room 4 will hand off control to this mission to SpaceX's mission control center in Hawthorne, California, where the company is headquartered.

Once astronauts Bob Behnken and Doug Hurley reach the space station, NASA personnel at Johnson Space Center in Houston will take center stage.