EXPOSITION PARK, LOS ANGELES (KABC) -- NASA's last remaining space shuttle external tank, known as ET-94, is scheduled to arrive in Marina del Rey in one week.Once it arrives in Marina del Rey, it will begin a several-hour long journey weaving through city streets en route to the California Science Center in Exposition Park on May 21.When it reaches its destination, it will join the space shuttle Endeavor, which made a similar journey in 2012."We knew it was out there and it was the only one that was left that was ready for flight and hadn't been used," Jeff Rudolph, the CEO of the California Science Center said.ET-94 started its 5,000 mile journey from New Orleans in April and has already made its way through the Panama Canal.Since the tank isn't as wide or as high as Endeavor, trees won't need to be cut down and fewer utilities will be impacted."We used a system called a 3D scan of the route and that gave us the exact height of all the cables and then we had to go by and figure out who owned those cables," Nate Miranda with the California Science Center said.The tank will become the second of three components needed to build a full stack replica for Endeavor's final display, upright, in the launch position.All that is needed now is the rocket boosters."To have a full stack of the full the space shuttle system of all the real hardware, it will be the only place in the world you will be able to see that, and it's really inspiring, which is our goal to inspire the next generation," Rudolph said.Spectators along the route on May 21 will not only see the external tank, but also roughly a dozen astronauts will walk alongside ET-94 as it makes its trip to the California Science Center.