SLS launches Orion to the Moon

On Wednesday, November 16, the super heavy lift rocket aiming to return humans to the lunar surface launched on its debut flight. The Space Launch System (SLS) originally scheduled to launch in 2016, lifted the Orion spacecraft off the ground and on the way to Moon orbit.

Shortly before liftoff, SLS ignited four RS-25 engines which were formerly used as Space Shuttle Main Engines in 120 milliseconds intervals to ensure that acoustic energy levels and start transients are within vehicle limits. After four healthy main engines had started, the command to ignite the Solid Rocket Boosters (SRBs) and release all umbilicals was sent. At this point, the vehicle was committed to launching. A few seconds after lifting off, the main engines gimbaled their thrust to ensure a proper azimuth or compass heading, needed to obtain the correct initial Earth parking orbit.

T+2 minutes and 12 seconds into the flight, the twin five-segment SRBs separated from the Core Stage, and at T+3 minutes and 19 seconds, the Launch Abort System (LAS) only intended to be used during anomaly situation separated. The Core Stage targeting an unstable 30 x 1805 km orbit, would ensure it reenters during its first orbit, breaking apart over a designated area of the Pacific Ocean. Main Engine Cutoff (MECO) occurs at T+8 minutes following stage separation. After a coast phase to apogee, the Interim Cryogenic Propulsion Stage (ICPS) ignites to increases the perigee to 185 km. Then, the Trans-Lunar Injection (TLI) burn which lasts about 18 minutes raises the orbital apogee out to the Moon for Orion to later insert itself into the Distant Retrograde Orbit. ICPS performs one more burn before separating into a heliocentric orbit.

Orion will remain in a Distant Retrograde Orbit around the Moon thousands of kilometers above the lunar surface before starting to return as early as December 1st followed by an atmospheric entry on December 11th. After a successful launch, if everything continues according to plan, the next mission, Artemis II – SLS and Orion’s first launch with astronauts aboard will take flight no earlier than (NET) 2024. Finally, Artemis III will with a help of SpaceX’s lunar Starship variant land astronauts on the Moon for the first time since 1972.