It's a cone 30 feet tall made of space age alloy. At the bottom, it's a little over 27 feet wide. At the top, just over 16 feet wide. And it's the biggest piece of Space Launch System (SLS) hardware to be built at NASA's Marshall Space Flight Center in Huntsville, Ala.

For all that, it's seeing how small the cone is on a scale model of SLS that makes the size of the new rocket begin to seem real. It is going to be huge.

NASA, Marshall and prime contractor Teledyne Brown Engineering teamed up on the cone officially called the launch vehicle stage adapter. They invited the media inside Marshall's National Center for Advanced Manufacturing Tuesday to see the finished article.

Well, the almost finished article. The final touch will be foam coating to insulate the adapter for its ride into space. That also comes at Marshall, and then the adapter is off to Cape Canaveral to await arrival of the remaining parts of the Space Launch System for the first flight.

The adapter's job is to join the core stage - the big bottom cylinder where the fuel and engines ride - to the upper stage containing the Orion capsule. For the first mission, Orion will detach from the adapter and fly more than 40,000 miles past the moon and back.

NASA adapter program manager Mindy Nettles said the contractor's role was special for those who know Rocket City history. "Teledyne Brown was Brown Engineering," Nettles said. "A Huntsville firm, a Huntsville organization" dating to 1954 and the early rockets of Wernher von Braun.

Teledyne Brown helped design the adapter, built its sections and delivered them to Marshall for assembly. It also built an identical test adapter that NASA has already successfully tested at Marshall.

"This is really what Marshall does and what we're good at," Nettles said.

The cone itself is made of an aluminum lithium alloy. It was built in curved wedge-shaped panels and welded together at Marshall using friction stir welding, a process where panels are actually melted together by incredible heat.

One of the biggest challenges was keeping the welds perfectly straight and parallel on the curved wedges, welding lead Jon Street said. That's critical so SLS flies straight.

Insulation manager Amy Buck, a materials engineer and Auburn University graduate, said her team will spray the insulation on the cone. "We have a portable dispense unit that will actually carry the foam material - it's actually a two-component material that stays separate until it gets to the gun - and then there will be a guy in a lift with a spray gun and he will be spraying the article by hand," Buck said.

"The manual process was easier and less costly because this is a one-off article," Buck said. "For the core stage that is planning to make more than one vehicle, they are using a lot more automated processes."

The adapter will leave Marshall sometime next year by barge for its journey to Cape Canaveral. The first launch of SLS is expected to be in 2019.

(Updated Sept. 1, 2017, to correct a statement that the adapter is the largest piece of space hardware ever built at Marshall. Larger parts of the Saturn V were built there. It is the largest piece of the Space Launch System built at Marshall.)