#nasasls

Because space is vast and full of mysteries, NASA is developing a new rocket, a new spacecraft for astronauts and new facilities to launch them from. Our Space Launch System will be unlike any other rocket when it takes flight. It will be bigger, bolder and take astronauts and cargo farther than humankind has ever been -- to deep space destinations like the moon, a deep space gateway or even Mars. 

The Gravity-Slayer

When you plan to get to space, you use ice and fire. NASA’s Space Launch System uses four rocket engines in the center of the rocket and a pair of solid rocket boosters on opposite sides. All this power will propel the Space Launch System to gravity-slaying speeds of more than 17,000 miles per hour! These are the things we do for space exploration, the greatest adventure that ever was or will be.

It is Known

It is known that according to Newton’s third law, for every action there is an equal and opposite reaction. That’s how rocket propulsion works. Fuel burned in combustion chambers causes hot gases to shoot out the bottom of the engine nozzles. This propels the rocket upward. 

Steammaker

It is also known that when you combine hydrogen and oxygen you get: water. To help SLS get to space, the rocket’s four RS-25 engines shoot hydrogen and oxygen together at high speeds, making billowing clouds of steaming hot water vapor. The steam, funneled through the engine nozzles, expands with tremendous force and helps lift the rocket from the launchpad. 

RS-25: Ice King

It takes a lot of fuel (hydrogen) and a lot of oxygen to make a chemical reaction powerful enough to propel a rocket the size of a skyscraper off the launch pad. To fit more hydrogen and oxygen into the tanks in the center of the rocket where they’re stored, the hydrogen and oxygen are chilled to as low as -400 degrees Fahrenheit. At those temperatures, the gases become icy liquids. 

The Fire that Burns Against the Cold

The hydrogen-oxygen reaction inside the nozzles can reach temperatures up to 6,000 degrees Fahrenheit (alas, only Valyrian steel could withstand those temperatures)! To protect the nozzle from this heat, the icy hydrogen is pumped through more than a thousand small pipes on the outside of the nozzle to cool it. After the icy liquid protects the metal nozzles, it becomes fuel for the engines. 

Where is my FIRE?

The Space Launch System solid rocket boosters are the fire and the breakers of gravity’s chains. The solid rocket boosters’ fiery flight lasts for two minutes. They burn solid fuel that’s a potent mixture of chemicals the consistency of a rubber eraser. When the boosters light, hot gases and fire are unleashed at speeds up to three times the speed of sound, propelling the vehicle to gravity-slaying speed in seconds. 

Testing is Here

To make sure everything works on a rocket this big, it takes a lot of testing before the first flight. Rocket hardware is rolling off production lines all over the United States and being shipped to testing locations nationwide. Some of that test hardware includes replicas of the giant tanks that will hold the icy hydrogen and oxygen.

As Rare as Dragonglass

Other tests include firing the motor for the solid rocket boosters. The five-segment motor is the largest ever made for spaceflight and the part that contains the propellant that burns for two fiery, spectacular minutes. It’s common during ground test firings for the fiery exhaust to turn the sand in the Utah desert to glass.

Hold the Door

When all the hardware, software and avionics for SLS are ready, they will be shipped to Kennedy Space Center where the parts will be assembled to make the biggest rocket since the Saturn V. Then, technicians will stack Orion, NASA’s new spacecraft for taking astronauts to deep space, on top of SLS. All this work to assemble America’s new heavy-lift rocket and spacecraft will be done in the Vehicle Assembly Building -- one of the largest buildings in the world. Hold the door to the Vehicle Assembly Building open, because SLS and Orion are coming!

Learn more about our Journey to Mars here: https://www.nasa.gov/topics/journeytomars/index.html