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[Music]

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The Space Launch System’s Core

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Stage is the framework of the

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world’s most powerful rocket.

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But before it’s assembled and

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integrated into SLS, the Core

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Stages five sections will need a

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combination of more than 750

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censors, 45 miles of cabling and

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100,000 fasteners. All that work

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is being done as we speak! Let’s

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take a closer look.

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[Music]

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At the base of the Core Stage

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sits the Engine Section, home to

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the four RS-25 engines, the

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thrust structure they push

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against, as well as more than 18

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miles of cables. Because of this

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section’s complexity and the

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extreme temperatures and

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vibrations it will experience,

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nearly 500 sensors are being

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installed in the engine section

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to monitor conditions.

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[Music]

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The Core Stage contains two

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separate fuel sources: The

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Liquid Hydrogen Tank, and the

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Liquid Oxygen Tank. Together,

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they hold a combination of

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733,000 gallons of propellant.

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[Music]

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This fuel is kept so cold that

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it will actually shrink the

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tanks up to 6 inches in length

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and more than 1 inch in diameter

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before they expand again as the

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fuel empties. That means that

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anything attached to the tanks

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must be secured with a variety

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of flexible or accordion-like or

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telescoping connectors.

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[Music]

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The Intertank is designed to

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connect the two fuel tanks. It

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isn’t being welded together like

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the rest of SLS. The Intertank

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is being put together by 14,500

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custom bolts, fasteners, and

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fittings. The “brain” of SLS is

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in its forward skirt section.

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The 45 miles of cables

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controlling the SLS eventually

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lead to the forward skirt

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section, where 3 flight

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computers monitor more than

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1,100 sensors to ensure a

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successful flight. Power for the

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computers and other core stage

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electronics is provided by four

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lithium ion batteries. Each is

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about the size of an average car

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battery and provides about 1.8

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kilowatts of power for the

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rocket’s 10-minute mission.

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[Music]

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NASA Engineers are working hard

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as we speak to make sure that

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every part of the Core Stage is

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outfitted and tested. But that’s

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just the beginning. Once the

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individual sections are complete,

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the whole thing needs to be

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assembled… but we’ll save that